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11 11 I 18

125 1611111125 1111114 16 11111 11111 14 11111 11111

MICROCOPY RESOLUTJON TEST CHART MICROCOPY RESOLUTION TEST CHART NATIONAL BUREAU or STANOARDS-1963-A NATiONAL BUREAU OF SIANDARDS-1963-A

bull

ET__

Technical Bulletin No 1005 March 1950

UNITED STATES

W ASBINGTON

Anthracnose of Cereals and Grasses l

By G y llltUl~HL ailJociate pathologist Dilision of OCIeal Olos alld Diseases Burean of Plant 1milllJtlY Soils alld dlrieultuIal EIIlinecIilll dUIicnltuml ReselIch AdmiliistllItion Ullitcd States Depaltment of Aglicultlllc Ilnd forshymerly ICllc(tch assistant Wiscollsin AlIicultllra~Expelilllellt Stlltion Ilnd J G DICKSON plOfeS80l at plant pathololY lViscolIsin IYIicllUural Experiment Station auli ogellt DitilJion of Celcal OlOPS alld Discases

CONTE~middotUS

Puge ugentwduction _________ _________ _ 1 Pathological histology of anthracshynose ______________________ _ Intluence of elllirUlllicut 011 the 15

develupment ()f ullthracnose_ 2 Disease lielcluplllent aIllI hisshytology ____________________ leulllemture reactiou of the 15pathogen ________________ _ Diseussion ___________________2 29Summary____________________Anthracnose develuLJlllent 011 30 SlIlan glass seedlings ill the Physiological lSllccializatiun inlreellhouse _______________ _ 4 Colletot Iiclwin graminicoshy

bull 111m ______________________ _ Authracnose de~olllllent on 30

rye seedlings Ii the green- Materials ami Illctholis ______ _ 31house _________ ____________~ s Experimental results_________ 32 Anthranotle dl1iioPUlCllt on Discussion and summary____ 35Conclusions ___________________ _~Ufml ~s llllll slwing rye 35

10 Litern t 11 cited _______________ _LU bull fijjl)----c)---------- shy 36 Disc~ioncr----=----------- 14Sum~ly_---~__________ _ 15 = 91 a

o 0 ~ ~ c pound INTRODUCTION ~ ltr ~

Ant~lenose o5l~leitls and grasses caused by Oolletotlichum gmmishyuiolwn (Ces) ~ Y Yils has been increasing in importance in leCent years DtOnage to oats and rye has been heavy in localized areas and the di~se has bel1l prominent on Sudan grass and a number of perennial grasses oer relatively wide areas

1 SuullIittel for pnblication SllltcmbeL G lOmiddotH) Cooperatiye illYestigations of the Dilision of Cerenl Crops uncI Diseases Burelu of Plant Industry Soils and Agrieultullll Engineprilg Agricultural Research Administration United States Dcpartmcllt of Agriculture and the Wisconsin Agricultural Experiment Station

bull Lclmowledgment is mude to D C Smith -Wisconsin Agricultural Experiment

~tation and to T L Allison Dhision of Porage Crops and Diseases Bmeau of Plnnt Industry Soils and Agricultural Engineering for cooperation in this investishygation Crellit iii ghcll to Eugene Herrling of the Department of Plant Pathology Cnhcrsity of -isconsin for the plwtograllhs

Submitted as a thesis to the graduate sehool of the lJniyelsity of Wisconsin ill [Hlrtial fUltillm(gtllt of the requirements for the degree of Doctor of Philosophy

S(i1~-n-uO--l

2 lECHNICAL BULLElIN 1005 U S DEPT OF AGlUCULlURE

This bulletin in tliree sections covers investigations of (1) influence of environment on the development of anthracnose (2) pathological histology of anthracnose and (3) physiological specialization in bull Oolletotrlahwm g1Ctminioo7ttnl

INFLUENCE OF ENVIRONMENT ON THE DEVELOPMENT OF ANTHRACNOSE

Various investigators have studied certain phases of the complex of anthracnose on particulttr hosts stimulated largely by some peculiar destructive manifestation of the disease Many have witnessed occashysional epiphytotics of the malady on some of the celeals 01 grasses with the subsidence of the disease in subsequent sea SOliS into an Itppurshyently minor root and crown rot The disease has been destructive on the roots crown leaves and inflorescence of Sudan grass in the northshycentral humid urea The disease has been severe on some hosts in midsnmmer and on many cereals and grasses in late summer and autumn as the plants approach maturity Specialization of the pltthoshygen environmental conditions aacl the effects of soil microflom 011

the causal fungus have had important relationships with this disease complex

TEMPERATURE REACTION OF THE PATHOGEN

The temperature responses of 21 isolates from graminicolous hosts were determined as one phase of the environmental study of the anthracnose disease ~1S field obsenations had indicated the aggressive development of the disease lIJldel different environmental conditions bull in the seve~al groups of hosts This was indicated also in the literature on the disease (93481418 19 ~z i~7)3

Conidia of the fungus ylte isolated by the dilution-plate method Acervu1i-bearing conidia CLe placed in a drop of sterile water on a sterile glass slide and examined The suspension was then streaked across poured plates of acidified potato-dextrose agar and colonies were transferred soon after conidial germination to avoid overgrowth by contaminants

The various isolates were compared when grown on potato-dextrose 4

agar at 4deg temperatme intervals from 12deg to 3(0 C Five-111m disks cut from the advancing malgill of colonies grown 4 days at 28deg served as the inoculum The number of replicates varied from two to four All plate were incubated 5 dl~Ys at which tim~ the isolates J~UlIing the most bull apld growth were neanng the marglll of the plates fhe clamshyeter of the mycelial mat was measured in two directions and the average diameter minus the 5-mm diskii was Lmiddotecordecl The isolates compared al(lnumber of replicates used arc indicated in table 1 The results are summarized in figme 1 by tribes of glllss hosts

Halil nlll1b~ls in 1arrlJth~s(S rlf~1 to Lit(latllr~ Iit(ll p Hi 10 grams of llextrose per litelmiddot

bull

3

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

TABLE 1-Sowoes Of isolates of OolletotrichUlTn U1arninicolurn and mtrnbe1 of eplicates 1tsed ill the studies of responses

Host iwlated from- Iocatiotl Replishycations

Tribe AgrostidcaeRedtop Agrostis alba IJ__ bull___ _ _bullbull _ ___ bull _ Boyd Wis_____ bullbull 4

Do__________ __ _ _ Chetek Wis ____ bull 4 Colonial bellt A elluis Sibth_____ n bullbullbullbullbullbullbull Hancock Wis__ _ 4 Timothy Phcum praiclIJle L_ __ bullbullbullbullbull _bullbullbull _ Poynette Wis_ 4

1---Total ___ bull ___ bullbullbullbull _bullbullbullbullbullbullbullbullbullbullbullbull _bullbullbullbullbullbull 16

Tribe Andropogonelle ohllson gruss Sorghum halepcII8e (h) Pers I _ bullbull Louisdlle Kybullbullbull__ 4Johnson gruss S haiepelisc (sector of above) __ _ bullbullbulldobullbull _ __ bull ___ 4Leoti sorghum S vulgare Pers2 bullbull ___ bullbull Bcitsville Md__ bull __ _____ do_________ bull 4Tift Sudlln gruss S vulgare vur BudalClIse 4(Piper) IIitch2

Common Sudnn gruss S vlIlgcvc vur sudallellsc Madison Wis ____ bull 4(Pipcr) Hitch2

Totul bullbullbull ________ bull __ _ __ bull __ _ 20

lribe AvenNle Onts Avella saiv(t L __ bull _bull __ _ bull __ Ellu Clnire Wis __ _ 400__bullbullbull _ ____ bullbull _____ _ Columbus Wis ___ 4

TotaL __ _ _bullbullbullbull __ bullbullbull _bull ~ _ _ 8

Tribe FesLuccae Orchard gruss Ductyiis glomeraa J) ___ _ ~Iarshfield Wis 3

])o____ _ -__~_ ____ _ ____ ~_ ~Iadison Vis___ 3 Mcndow fe$cue FestllClt clatior L bullbullbull _ bull Hancock Wis __ 3 Sheep fcscue F oviICL r ___ ___ _ Portage Wis ___ _ 3 Red fescue F rubra L ___ bull - _ HUllcock Wis bull_ 3 Ken tucky blucgrnss Poa middotprutellsi~ L _ _ Boyd Wigt_bullbull _ 3

00____ bull ____ bull ___ bull __ _ bullbullbullbull __ do ______ bullbullbullbull 3gt bull ____

Do __ Plninfield Wis _ 3 Do _ bull bull Povllette Wis____ 3 Do_ bull - - _ _ Pnckwnukce Wis 3

1----Totul_ bullbull __ 30

Tribe Hordene Crested whelltgruss AgropyrOli cri~atllm (I) JIllncock Wis ____ _ 2

GlLertn Qunekgruss It r(pens Cr) Benuv__ bull ______ Plninfield Wis bullbull 2 B1uestem fl smilhii llydb__ _ Hnncock Wis Slender whcutgrnss 11 trachycCllllIIlt (Liuk) I Ln Fnyettc Indbull 2

2

~lulte3 Sibcrinll wildmiddotrye Elymlt~ gi(lilllell~ Vahl3 bullbull ___ ___ do____ bull _____bull 4 Blue wildnmiddotc E gl(WCll~ Buckl3 _ l _____ do___ bull _ lt1 Bnrley lorecum vulgare L__ __ i Columbus Wis bullbull__ 4 nyc sceCllc cereal) IJ __ bull _ Pnckwlllkee WIS_ 4

Tut-a - - _____ _ _ _ ___ __ - __________ bull _____ 1---shy24

I lirom Il hcrbarlum specimen tOffectod by Ellnr Nlelscn 1 ObLnincU from O [ bull Lefebvre 1 With tho tlSSistlUlCtl of J Ralph ahny

4 middotlEGfLnCAL BULLETIN 1005 U S DEPT OF AGlUCUUlURE

The ratio of mycelial development of the Oolletotlictwm glamishyjdcolu1n isolaes indicated differences in temperature response 1soshylates from cereals and gtasses with vegetative development in the cool periods of full and spring grew more Iapidly at low temperature than did those from Sorghum spp (Andropogoneae) lmving vegeshytative development during the WIllm summer Conversely isolates ftom SO~gln(Jn spp grew 11101e rapidly at high(~ tempelatures tlum did the isolates from the other gmsses (fig 1) This moderate corshyrelation of the temperature requirements of Ole isolates with those of their hosts indicates u general adnptation of parasite to host

10degr-------~-------r------~~~~~~~~==-------1

90~------_+---------~---shy

80~------_+----~--ff

t=z 70 f-------I-- shyw u II

~ 601--------LI

t I shy

~ 50 a

w 40 ANOROPOCONEAE ---~I--shygt

----1--- __ = ACROST I DEAE

I shy ---IESTUCEAElt bullbull_ bullbullbullbullbullbullbullbull HORDEAEJ oJ bull - bull _ AV E NEAE=--_----lII

10r--------t--------4---------I--------+--------+--------shy

~2~middot------~1~6~middot------~2fO~middot------~2~4middot~----~2~8middot~----~J~27------~36 TEMPERATURE (c)

FIGtla l-R(latin lllycelial growth of isolat(s o( (ollefofdcll11I1 II(IIlinicolllll~ at ditYel(lIt il11I(l(llttIll(8 Ioll(llll by tlibes o( 1118S hosts the mllximum growth of (I(h group tnelllls ]00 INC(nt

The ccologkal signifieanee of difrel(Il(es in templlatllle response in these ttibal groupings was emphasized by using the Andlopogoneae group mean ns the standtllCl (fig 2)

A~TlIRACNOSE DEVELOPMENT OX SCDX GHASS SEEDLI~GS 1 TilE GHEENIIOUSE

The seedling phase of anthraenoS on Hudan grass and rn as studied in the geenhowlc undeL diflcrent pnvirOlllnental conditions On Hudan grass t he disease was eharaetcrizecl by loss of bright-green (0101 wilting alld (olillps( aboc gronnd Thesc symptoms wCle prodll(ed by a 1H(Iosis of the Iilst intlLnocle and seminal oots much the same as found in oats by ~llnfonl (lL in COlll by Bocning allli

bull

bull

bull

2 lECHNICAL BULLElIN 1005 U S DEPT OF AGlUCULlURE

This bulletin in tliree sections covers investigations of (1) influence of environment on the development of anthracnose (2) pathological histology of anthracnose and (3) physiological specialization in bull Oolletotrlahwm g1Ctminioo7ttnl

INFLUENCE OF ENVIRONMENT ON THE DEVELOPMENT OF ANTHRACNOSE

Various investigators have studied certain phases of the complex of anthracnose on particulttr hosts stimulated largely by some peculiar destructive manifestation of the disease Many have witnessed occashysional epiphytotics of the malady on some of the celeals 01 grasses with the subsidence of the disease in subsequent sea SOliS into an Itppurshyently minor root and crown rot The disease has been destructive on the roots crown leaves and inflorescence of Sudan grass in the northshycentral humid urea The disease has been severe on some hosts in midsnmmer and on many cereals and grasses in late summer and autumn as the plants approach maturity Specialization of the pltthoshygen environmental conditions aacl the effects of soil microflom 011

the causal fungus have had important relationships with this disease complex

TEMPERATURE REACTION OF THE PATHOGEN

The temperature responses of 21 isolates from graminicolous hosts were determined as one phase of the environmental study of the anthracnose disease ~1S field obsenations had indicated the aggressive development of the disease lIJldel different environmental conditions bull in the seve~al groups of hosts This was indicated also in the literature on the disease (93481418 19 ~z i~7)3

Conidia of the fungus ylte isolated by the dilution-plate method Acervu1i-bearing conidia CLe placed in a drop of sterile water on a sterile glass slide and examined The suspension was then streaked across poured plates of acidified potato-dextrose agar and colonies were transferred soon after conidial germination to avoid overgrowth by contaminants

The various isolates were compared when grown on potato-dextrose 4

agar at 4deg temperatme intervals from 12deg to 3(0 C Five-111m disks cut from the advancing malgill of colonies grown 4 days at 28deg served as the inoculum The number of replicates varied from two to four All plate were incubated 5 dl~Ys at which tim~ the isolates J~UlIing the most bull apld growth were neanng the marglll of the plates fhe clamshyeter of the mycelial mat was measured in two directions and the average diameter minus the 5-mm diskii was Lmiddotecordecl The isolates compared al(lnumber of replicates used arc indicated in table 1 The results are summarized in figme 1 by tribes of glllss hosts

Halil nlll1b~ls in 1arrlJth~s(S rlf~1 to Lit(latllr~ Iit(ll p Hi 10 grams of llextrose per litelmiddot

bull

3

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

TABLE 1-Sowoes Of isolates of OolletotrichUlTn U1arninicolurn and mtrnbe1 of eplicates 1tsed ill the studies of responses

Host iwlated from- Iocatiotl Replishycations

Tribe AgrostidcaeRedtop Agrostis alba IJ__ bull___ _ _bullbull _ ___ bull _ Boyd Wis_____ bullbull 4

Do__________ __ _ _ Chetek Wis ____ bull 4 Colonial bellt A elluis Sibth_____ n bullbullbullbullbullbullbull Hancock Wis__ _ 4 Timothy Phcum praiclIJle L_ __ bullbullbullbullbull _bullbullbull _ Poynette Wis_ 4

1---Total ___ bull ___ bullbullbullbull _bullbullbullbullbullbullbullbullbullbullbullbull _bullbullbullbullbullbull 16

Tribe Andropogonelle ohllson gruss Sorghum halepcII8e (h) Pers I _ bullbull Louisdlle Kybullbullbull__ 4Johnson gruss S haiepelisc (sector of above) __ _ bullbullbulldobullbull _ __ bull ___ 4Leoti sorghum S vulgare Pers2 bullbull ___ bullbull Bcitsville Md__ bull __ _____ do_________ bull 4Tift Sudlln gruss S vulgare vur BudalClIse 4(Piper) IIitch2

Common Sudnn gruss S vlIlgcvc vur sudallellsc Madison Wis ____ bull 4(Pipcr) Hitch2

Totul bullbullbull ________ bull __ _ __ bull __ _ 20

lribe AvenNle Onts Avella saiv(t L __ bull _bull __ _ bull __ Ellu Clnire Wis __ _ 400__bullbullbull _ ____ bullbull _____ _ Columbus Wis ___ 4

TotaL __ _ _bullbullbullbull __ bullbullbull _bull ~ _ _ 8

Tribe FesLuccae Orchard gruss Ductyiis glomeraa J) ___ _ ~Iarshfield Wis 3

])o____ _ -__~_ ____ _ ____ ~_ ~Iadison Vis___ 3 Mcndow fe$cue FestllClt clatior L bullbullbull _ bull Hancock Wis __ 3 Sheep fcscue F oviICL r ___ ___ _ Portage Wis ___ _ 3 Red fescue F rubra L ___ bull - _ HUllcock Wis bull_ 3 Ken tucky blucgrnss Poa middotprutellsi~ L _ _ Boyd Wigt_bullbull _ 3

00____ bull ____ bull ___ bull __ _ bullbullbullbull __ do ______ bullbullbullbull 3gt bull ____

Do __ Plninfield Wis _ 3 Do _ bull bull Povllette Wis____ 3 Do_ bull - - _ _ Pnckwnukce Wis 3

1----Totul_ bullbull __ 30

Tribe Hordene Crested whelltgruss AgropyrOli cri~atllm (I) JIllncock Wis ____ _ 2

GlLertn Qunekgruss It r(pens Cr) Benuv__ bull ______ Plninfield Wis bullbull 2 B1uestem fl smilhii llydb__ _ Hnncock Wis Slender whcutgrnss 11 trachycCllllIIlt (Liuk) I Ln Fnyettc Indbull 2

2

~lulte3 Sibcrinll wildmiddotrye Elymlt~ gi(lilllell~ Vahl3 bullbull ___ ___ do____ bull _____bull 4 Blue wildnmiddotc E gl(WCll~ Buckl3 _ l _____ do___ bull _ lt1 Bnrley lorecum vulgare L__ __ i Columbus Wis bullbull__ 4 nyc sceCllc cereal) IJ __ bull _ Pnckwlllkee WIS_ 4

Tut-a - - _____ _ _ _ ___ __ - __________ bull _____ 1---shy24

I lirom Il hcrbarlum specimen tOffectod by Ellnr Nlelscn 1 ObLnincU from O [ bull Lefebvre 1 With tho tlSSistlUlCtl of J Ralph ahny

4 middotlEGfLnCAL BULLETIN 1005 U S DEPT OF AGlUCUUlURE

The ratio of mycelial development of the Oolletotlictwm glamishyjdcolu1n isolaes indicated differences in temperature response 1soshylates from cereals and gtasses with vegetative development in the cool periods of full and spring grew more Iapidly at low temperature than did those from Sorghum spp (Andropogoneae) lmving vegeshytative development during the WIllm summer Conversely isolates ftom SO~gln(Jn spp grew 11101e rapidly at high(~ tempelatures tlum did the isolates from the other gmsses (fig 1) This moderate corshyrelation of the temperature requirements of Ole isolates with those of their hosts indicates u general adnptation of parasite to host

10degr-------~-------r------~~~~~~~~==-------1

90~------_+---------~---shy

80~------_+----~--ff

t=z 70 f-------I-- shyw u II

~ 601--------LI

t I shy

~ 50 a

w 40 ANOROPOCONEAE ---~I--shygt

----1--- __ = ACROST I DEAE

I shy ---IESTUCEAElt bullbull_ bullbullbullbullbullbullbullbull HORDEAEJ oJ bull - bull _ AV E NEAE=--_----lII

10r--------t--------4---------I--------+--------+--------shy

~2~middot------~1~6~middot------~2fO~middot------~2~4middot~----~2~8middot~----~J~27------~36 TEMPERATURE (c)

FIGtla l-R(latin lllycelial growth of isolat(s o( (ollefofdcll11I1 II(IIlinicolllll~ at ditYel(lIt il11I(l(llttIll(8 Ioll(llll by tlibes o( 1118S hosts the mllximum growth of (I(h group tnelllls ]00 INC(nt

The ccologkal signifieanee of difrel(Il(es in templlatllle response in these ttibal groupings was emphasized by using the Andlopogoneae group mean ns the standtllCl (fig 2)

A~TlIRACNOSE DEVELOPMENT OX SCDX GHASS SEEDLI~GS 1 TilE GHEENIIOUSE

The seedling phase of anthraenoS on Hudan grass and rn as studied in the geenhowlc undeL diflcrent pnvirOlllnental conditions On Hudan grass t he disease was eharaetcrizecl by loss of bright-green (0101 wilting alld (olillps( aboc gronnd Thesc symptoms wCle prodll(ed by a 1H(Iosis of the Iilst intlLnocle and seminal oots much the same as found in oats by ~llnfonl (lL in COlll by Bocning allli

bull

bull

bull

3

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

TABLE 1-Sowoes Of isolates of OolletotrichUlTn U1arninicolurn and mtrnbe1 of eplicates 1tsed ill the studies of responses

Host iwlated from- Iocatiotl Replishycations

Tribe AgrostidcaeRedtop Agrostis alba IJ__ bull___ _ _bullbull _ ___ bull _ Boyd Wis_____ bullbull 4

Do__________ __ _ _ Chetek Wis ____ bull 4 Colonial bellt A elluis Sibth_____ n bullbullbullbullbullbullbull Hancock Wis__ _ 4 Timothy Phcum praiclIJle L_ __ bullbullbullbullbull _bullbullbull _ Poynette Wis_ 4

1---Total ___ bull ___ bullbullbullbull _bullbullbullbullbullbullbullbullbullbullbullbull _bullbullbullbullbullbull 16

Tribe Andropogonelle ohllson gruss Sorghum halepcII8e (h) Pers I _ bullbull Louisdlle Kybullbullbull__ 4Johnson gruss S haiepelisc (sector of above) __ _ bullbullbulldobullbull _ __ bull ___ 4Leoti sorghum S vulgare Pers2 bullbull ___ bullbull Bcitsville Md__ bull __ _____ do_________ bull 4Tift Sudlln gruss S vulgare vur BudalClIse 4(Piper) IIitch2

Common Sudnn gruss S vlIlgcvc vur sudallellsc Madison Wis ____ bull 4(Pipcr) Hitch2

Totul bullbullbull ________ bull __ _ __ bull __ _ 20

lribe AvenNle Onts Avella saiv(t L __ bull _bull __ _ bull __ Ellu Clnire Wis __ _ 400__bullbullbull _ ____ bullbull _____ _ Columbus Wis ___ 4

TotaL __ _ _bullbullbullbull __ bullbullbull _bull ~ _ _ 8

Tribe FesLuccae Orchard gruss Ductyiis glomeraa J) ___ _ ~Iarshfield Wis 3

])o____ _ -__~_ ____ _ ____ ~_ ~Iadison Vis___ 3 Mcndow fe$cue FestllClt clatior L bullbullbull _ bull Hancock Wis __ 3 Sheep fcscue F oviICL r ___ ___ _ Portage Wis ___ _ 3 Red fescue F rubra L ___ bull - _ HUllcock Wis bull_ 3 Ken tucky blucgrnss Poa middotprutellsi~ L _ _ Boyd Wigt_bullbull _ 3

00____ bull ____ bull ___ bull __ _ bullbullbullbull __ do ______ bullbullbullbull 3gt bull ____

Do __ Plninfield Wis _ 3 Do _ bull bull Povllette Wis____ 3 Do_ bull - - _ _ Pnckwnukce Wis 3

1----Totul_ bullbull __ 30

Tribe Hordene Crested whelltgruss AgropyrOli cri~atllm (I) JIllncock Wis ____ _ 2

GlLertn Qunekgruss It r(pens Cr) Benuv__ bull ______ Plninfield Wis bullbull 2 B1uestem fl smilhii llydb__ _ Hnncock Wis Slender whcutgrnss 11 trachycCllllIIlt (Liuk) I Ln Fnyettc Indbull 2

2

~lulte3 Sibcrinll wildmiddotrye Elymlt~ gi(lilllell~ Vahl3 bullbull ___ ___ do____ bull _____bull 4 Blue wildnmiddotc E gl(WCll~ Buckl3 _ l _____ do___ bull _ lt1 Bnrley lorecum vulgare L__ __ i Columbus Wis bullbull__ 4 nyc sceCllc cereal) IJ __ bull _ Pnckwlllkee WIS_ 4

Tut-a - - _____ _ _ _ ___ __ - __________ bull _____ 1---shy24

I lirom Il hcrbarlum specimen tOffectod by Ellnr Nlelscn 1 ObLnincU from O [ bull Lefebvre 1 With tho tlSSistlUlCtl of J Ralph ahny

4 middotlEGfLnCAL BULLETIN 1005 U S DEPT OF AGlUCUUlURE

The ratio of mycelial development of the Oolletotlictwm glamishyjdcolu1n isolaes indicated differences in temperature response 1soshylates from cereals and gtasses with vegetative development in the cool periods of full and spring grew more Iapidly at low temperature than did those from Sorghum spp (Andropogoneae) lmving vegeshytative development during the WIllm summer Conversely isolates ftom SO~gln(Jn spp grew 11101e rapidly at high(~ tempelatures tlum did the isolates from the other gmsses (fig 1) This moderate corshyrelation of the temperature requirements of Ole isolates with those of their hosts indicates u general adnptation of parasite to host

10degr-------~-------r------~~~~~~~~==-------1

90~------_+---------~---shy

80~------_+----~--ff

t=z 70 f-------I-- shyw u II

~ 601--------LI

t I shy

~ 50 a

w 40 ANOROPOCONEAE ---~I--shygt

----1--- __ = ACROST I DEAE

I shy ---IESTUCEAElt bullbull_ bullbullbullbullbullbullbullbull HORDEAEJ oJ bull - bull _ AV E NEAE=--_----lII

10r--------t--------4---------I--------+--------+--------shy

~2~middot------~1~6~middot------~2fO~middot------~2~4middot~----~2~8middot~----~J~27------~36 TEMPERATURE (c)

FIGtla l-R(latin lllycelial growth of isolat(s o( (ollefofdcll11I1 II(IIlinicolllll~ at ditYel(lIt il11I(l(llttIll(8 Ioll(llll by tlibes o( 1118S hosts the mllximum growth of (I(h group tnelllls ]00 INC(nt

The ccologkal signifieanee of difrel(Il(es in templlatllle response in these ttibal groupings was emphasized by using the Andlopogoneae group mean ns the standtllCl (fig 2)

A~TlIRACNOSE DEVELOPMENT OX SCDX GHASS SEEDLI~GS 1 TilE GHEENIIOUSE

The seedling phase of anthraenoS on Hudan grass and rn as studied in the geenhowlc undeL diflcrent pnvirOlllnental conditions On Hudan grass t he disease was eharaetcrizecl by loss of bright-green (0101 wilting alld (olillps( aboc gronnd Thesc symptoms wCle prodll(ed by a 1H(Iosis of the Iilst intlLnocle and seminal oots much the same as found in oats by ~llnfonl (lL in COlll by Bocning allli

bull

bull

bull

4 middotlEGfLnCAL BULLETIN 1005 U S DEPT OF AGlUCUUlURE

The ratio of mycelial development of the Oolletotlictwm glamishyjdcolu1n isolaes indicated differences in temperature response 1soshylates from cereals and gtasses with vegetative development in the cool periods of full and spring grew more Iapidly at low temperature than did those from Sorghum spp (Andropogoneae) lmving vegeshytative development during the WIllm summer Conversely isolates ftom SO~gln(Jn spp grew 11101e rapidly at high(~ tempelatures tlum did the isolates from the other gmsses (fig 1) This moderate corshyrelation of the temperature requirements of Ole isolates with those of their hosts indicates u general adnptation of parasite to host

10degr-------~-------r------~~~~~~~~==-------1

90~------_+---------~---shy

80~------_+----~--ff

t=z 70 f-------I-- shyw u II

~ 601--------LI

t I shy

~ 50 a

w 40 ANOROPOCONEAE ---~I--shygt

----1--- __ = ACROST I DEAE

I shy ---IESTUCEAElt bullbull_ bullbullbullbullbullbullbullbull HORDEAEJ oJ bull - bull _ AV E NEAE=--_----lII

10r--------t--------4---------I--------+--------+--------shy

~2~middot------~1~6~middot------~2fO~middot------~2~4middot~----~2~8middot~----~J~27------~36 TEMPERATURE (c)

FIGtla l-R(latin lllycelial growth of isolat(s o( (ollefofdcll11I1 II(IIlinicolllll~ at ditYel(lIt il11I(l(llttIll(8 Ioll(llll by tlibes o( 1118S hosts the mllximum growth of (I(h group tnelllls ]00 INC(nt

The ccologkal signifieanee of difrel(Il(es in templlatllle response in these ttibal groupings was emphasized by using the Andlopogoneae group mean ns the standtllCl (fig 2)

A~TlIRACNOSE DEVELOPMENT OX SCDX GHASS SEEDLI~GS 1 TilE GHEENIIOUSE

The seedling phase of anthraenoS on Hudan grass and rn as studied in the geenhowlc undeL diflcrent pnvirOlllnental conditions On Hudan grass t he disease was eharaetcrizecl by loss of bright-green (0101 wilting alld (olillps( aboc gronnd Thesc symptoms wCle prodll(ed by a 1H(Iosis of the Iilst intlLnocle and seminal oots much the same as found in oats by ~llnfonl (lL in COlll by Bocning allli

bull

bull

bull

5 ANlHRAC~OSg 01 CI~HpoundALS AXD (lHASSJltJS

ValineI (3) and in SUdilll glliSS and rye ill thn ptes(lIt stud ies The mpiclity and exlellt of fungus illVltsioll illlo tho ]owel seedlillg axis

bull and seminal root system det(Illlill(~d in JIllgo purt I ho sevelity of sym ptOlllS Ilbovo grolilld

COII IllNcia I Texas-grown ltOllllrlOIl Sulllllt g1llss se(~d flco from damaged kelllels was surlace-sUmiddotIi Ii~e(l lillS(d a lid (Itjed Half the seed was i10(11 lated by submersion ullder pattiul enlClllltion in II

(Ioudy conidial SIISPlIISioll of the i8olah 110111 commOIl liul1all gLllSS

from lalli801l is a lid tho otllel Iml f oJ tho seed waS used as It

ColltloL fhe s(~cds WCllI planUmiddot1 in It (om posted Miami Hilt JOIUJ1

u 20 -lt u Z o o a o a o Igt Z -lt

bull u

o

gt ~ 10 J ANDROPOGONEAE a

00 12 16 20 24 26 32middot 311middot

TEM PEllATURE (C)

PWllt~ ~ 1 IU gl IlIy((1i1l1 gIoth of I~olll les of ((JICOi(IlIn fll1l11l ilOUII flIl11 IlIOliS lIiws ot grll$s ho~Ls (()IIlJlIlI(d with fhllt of (OIl(SJlOlldilll isolateh fOtll tht tribe I1I1IO[101(()II(II(middot Hill IJIISl 01 1 (ltlatH frOll1 tig J 1

inllllCdilltlly followillg sUal11 1(Iili~ali()n 101 middot1- hOlllS III I)OUlH1S PIlSSlIl ((Joling III(L allatiOJl jS((Hlsin 1111I1IlIIIIIII( lUll (S w(reshyused to (ontlol soil t(IllIWrltllllH af Hi W ~middotI S and ~2deg C Ail t(lIl1)IIHtUlCmiddots (1( within 10 of til( Hoil llIIII)(~Iallll(s T(I(~ G-j nell Ia~(d (In IU 1(1lIle potH Nil pill((ll i neal11 ia Ilk iloisllllC Il(IH IlI( (ontlollld lJ tll(1 nlllhod (JUtlin(d IW Hik(I and Hik(t (17) rrhll( di(a( (IISS( (1l IIS(( ill laking tll( dala aJld ealshy(tllatin till dis(lIsl indiets () fot h(allin ID Im wi 11(1 (ll dis(()I()n~d

bull plants 11 lid 100 JOI bligh((middotd s(ldlings~ TIlf lIho1 Illetllodi and IllnlCrial- ptl f()J thl III0St palL lIilClL ill a silllila ilhuly of the sCNliing phns( (If ulthllItIOSl of 1)(

bull bull bull

~400 100- r

~ ta90360

~ 60 I o320 I 32 Elt txl

260 ~ 70 IAJ U a I~~JJ vi ~ ~ IAJ ~ ~ 60 ~ ~ ~ I- I o 50 o i 111

~ 40~ 1601-f 1lZ JI I I -X I I I~ C t

tj~ 30 1

en

tj~ _~ CIII

20 - __ 171

gt 10 -~ _L--n - o

~

ltl

I I -Vi I ~ 8 I I I I I I I

o 16 19 20 21 22 23 244 5 6 7 6 9 10 II 12 7 6 ) 10 II 12 13 14 15 16 17 ~

ltl DAYS AFTER PLANT ING tj

~JGum a-Seedling emergence audbJight development of Sudan grass resulting from seed inoculated with Collctot-chmn uralllfnicQlll1n amI lliullted in sterilized soil at dlfterent temperatures

7 ANlHHACXOSB OF CEREALS AND GRASSES

EFFECT OF SOIL ilOISTURE AND TEiIPERATURE

Sudan grass seedlings developed disease at temperatures from 16deg 103ampdeg C Soil moistlll(~ levels of 35 and 50 percent satumtion showed little cliflerence in disease development so datu were combined in figure 3 lypicitl seedling bUght den~lopecl Itt Hio but emergence was so pOOL ill the controls that this temperature was omitted Disshyease development ttnd host ltlevelopment (as measured by mte of e~nelgenc~ and in(r~HSe in plant heigh~) were both direct~y proporshytlOllal to lI(I(I1S(S 111 tempemtute dUllIlg the short duratwn of the experiment IIj lUll seedllllg blight howevetmiddot was pmcticttlly the same at all temperatures lIsed~

100

II 90 STtRIL- f-- STERILIZEO-IZED

eo I- DRY r- shy 70 _~T_I-

middotTmiddotmiddot x oJ

0 60 I- - i=-- bullbullbullbullbull UIltSTERILIZEO

oJ ~o -lt

bull oJ o 40 I- shy

30 l- Ishy

20 i- Ishy

10 i- Ishy

0 -- _L- shy 20 24 28 32 STERILIZATION SOIL MOISTURE TEMPERATUREIC)

tJGlm 4-Efitet of oil 1lli1 iin tion soil 1JIoiitl1r( nllli 1l1II11ern fIIlC llpon the sC(ity oC IIl1thlll(II0se 011 ~ultlnll rus f(gtcdlillS

EFFpoundCT OF SOIf STEHILIZ ITIO SOIL IOISTeHE )0 TE~lPEItATUHE

c(onlt1 expeliJllelltin whieh stp)iliz((l and IInstelilizel1 soils were used showCli im pOllant di tl(l(lleeH ill lUsease lesponse to environshyment rnstCri liZId a nlt1 sleam-steli Iizeti ~[jami silt loams WCLe used nt two 1ll0istllLP ](pls (middotw and liO plr(ent sa(lIl11tion) and at temshyperatm( from W to a~ C at4-degree intela Is Half of each pot was plllnt(ld with ino(ulaled and half with ullino(ulateltl seed as pr(ious expetillHHts hall shown that the Jungns did not sprclHI rapidl thlOugh thl soil The plnntins were made lfalth 2 19+i

bull whcn light condit ions fa )1(1d a stHrdy nOlletiolated sedling (lOcI01)shymen rhe reml(s ntt iurnmarizlltlill figure ck

The investigations ith stlrilizNI and 1I11sllrilized soillen~ale(l that nnothel ftlctOl ioi I mi(loilorn fune ioned in the dcyelopment of anshy

8 IECHNICAL BULLE1IN 1005 U S DEPT OI~ AGRICULTUllE

thracnose on the undelglOllllll seedling tisswcs Apparently both soil temperature and moisture lnflllelHed the development of the soil mishyClOilOrH with a resulting indirect eflect on OolletotJichwn [Jlaminishy(oZlUn HIld disease development tlS shown by the contrast ill disease reaction in the stelilized lnclllnstelilized soils (fig 4) As in the preshyvious experiment the oveL-IlU eUect of teinpellltllle was not significant in sterilized soil In lInsterilizecl soil however disease developmcnt was less at low tempelatures than nt 33deg O Ample Soilllloistllle reshyduced disease incidence thlc tillles as H)uch in the Plps(~n(e of the soil mieloflom asin sl(lilizlel soil In moist ullsterilized soil them waR a low Ieel of diRtaSe at all templ1abnes clue apparently to the antagshyonistic action of soU microfoltl whtteas in dry soil the soil 111icroshyflom weremiddot in(leasingl inellecti( at himiddotrJt ttmplIaimes Apparently diSlase-hJlribiti ng biological factltHIe~ponded both to telll peratul(s and to 1Il0istule ill the uusteri Iizec1 oi 1

Alexopoulos (1) found that Actinomy((s spp ranged fLom strong inhibitors to noninhibitolfi of O flloeospolioides Penz Leben and Keitt (15) follnd that O fllrunini(olUin was inhibited by Rtloptomyccs sp AJthol1gh the evic1ell(e pnsenled in the 1)Jeslnt blllletin indicated that soil mielofl01lt played all importilnt lole in the development of the seedJj~lg cli)eas( of Sudall gltlss (lllsed by O rJIClmini(olum the lesults W(Ie 11IconduSlc

ANIHltCNOS~ D~VELOPiIE~T ox RYE SEELgtLJlXCS IN THE Cn~ENlIOUSE

The relation of elldlOlllllent to tlw delloplllent of the seedling phases of tllthla(lIosc 01 Ie was inetigatecl in a manner similtlL to that J(poried pound01 SlIdan glilS _ dill(pn( leSpOIlHe of host and parashysite to soil tempelutuIe waS lxplcteil as Iye seedlings elmelop best at low templlatules 10 elllpllahlll eli(H of rye seeellings were jnshy(stigated ulldel dif)elent h~ht (ol1clitiOIlS SClies A was grown in Apdl alld)lay Il17 lIndlr good light and long days series B was grown ill ])e((lIliJel 1fH7 dllling a doudy shOLt-day peliod

The llav(s of c1is(asPl] lye seedlings dpwlopec1 a Haccid conditioll followed by (rlolosis wlllJl in the thinl 01 10ll1Ih INLI stage amI subshysequent bUghtillg UI)(I(I (ondilionsfllolahlt fol (lisea5( declopment Neelosis of tlw IOCI1I0cC inte)nocles and selllinal LOOt5 caused these above-glound sympton)s Spdnr and Willltl IY( wPIe both sllseeptibh to the imlal(s of UoUrtotlictum (iltlmini(olulII fJom Ie Tlte san)( ryeisolatl o HIll palhog(llwas us(d in all (x]leliIlIPnts middotith In

EFFECT ov n[PIHAJCIIE SOIL STEHIJIZATJOX AND LIGHT

S(lies ~ WHi )OWn ill stHIll-HiC)ilizelt1 anltlunsteiliicd soil under fa orablp ] ight (oJl(li [iousbullplil ant1 )layIH7 The soil tempclashyllIJes llsedmngetl fJolll H to H C at middot1deg inlenals wit11 the ail temshypela tu Il hpId with i n bgt of the soi I t l1l1 pNai lle a t all but the HO soil telllshypcmtuIp at hiel) the air t(lllll)atu)( was 1UO Only one lank was used Ht ~8deg ilnd 3~o and data foe thcse i(Ill))(IJatUllH aJ( not included Steall1-stIilizcd lllid uJlRt(Iilize(L )[inmi silt loam ele llscd to COJl1shypalC he inflmncts of the soil mi(toflollL on fhl development of the

bull

bull

bull

bull

bull

bull

A~lHnACNOSE OF m~HEALS ANIgt GHASSES 9

disease at dincrellt tempelltttlLcs Soil moisturil gtas mainbtined at it level favoIable pound01 good plant growth The results Ilre summarized in (i(rme 5 it

s~il tcnpemtUlps infhlCIIltecl the dwelopmcllt of anthracnose in rye scedlings The soil micloflola in the llllsterllized soil modified the temperature response as shown in Sudnr gmss In this series gtown during the spling und(l good) ight ltoll(litions no disease tlmeloped ill the rye eelllings at 8deg soil tCllIpclnflllc and 16deg 0 ail temperature ill either the terilizcd 01 ullsterilizld soil ~t HO soil and 16deg nil tClllshypellltllLe It lIloderute level 0 f disease dceloped in the seril izetl soil alld but little in the lInstelilized soil At Wo and auol seltlling ([amagn WIIS S(lrein the sterilized soil with It disemie illttx of about 1)0 In IllUilNilizet soil Ih( ([isllIsl illlI(IISNI gradllally with It lisein telllshyp(lIltULe At ~Ho and 32deg sOll1e pr(~ltlI1ergence ulighting or tho scedshylings OCClIIIcd ill both stlliliz(d and III1SUIilizp(l SOl

DAYS ArTER PLNTINC

IOOJ~_-Z-7__~Z~J___~20-_~1~ IOO~~0-_--=3~l__~2~4---poundL-----Li

0 90

00

~ 10

~ ~ GO fiO

70

X ~ ~~ ~too

UtoULHutUi -0

~ 0 OJ 30 JO e tl I

I0 I I

A 10 B I

t

_oll~----i6-----~2~O----~24 oL8------1~2----~6~----~20~--~24 SOH fC-IIPCRoTURc(-C) SOIL T(UPCRATURr(middotC)

1IlJIIt~ jo-~Ihp illlhllI1(I of iilJll tlIII1Wrllilllp Roil SICIilizatioll nllt light 011 llldllll~ hlight of 111 (III1c(1 h Colcoridlllm I(IIIlIiIOIIlIl A RIPl1illg~ grol1 ill Rlpnllh~tlIiliz(lt1 nlld IIIIHttIillzp( l1illl1i silt loalll ill Sprillg limIer good light ((lIuliliolls i II 1lIItllillg rtl11 III fOIlIIalllh~II(lltlIillzld lllltlImilIl1izpt Miallli silt Imlill in illtlI IIl1dll IJOor light COIllIitiIIIIl

SlrilS n Was TOWll in Jormaldl~hy(l(-~t(liliztd soil tllldcr 1IIlfaomshyblolight lOIHlitloIlS lgtl(PlIIlJll (Il(fJanualY 1H-7-1H FOllIlaldehyde ~t(Li1izati(l1 was slibsi iluHd for Silalll Btelilizationin 01(1(1 too ledlHC thn ehnnges ill physi(al and (1tlIlieaI [HopPIIieR of Ill soil that lemlt (11)111 SitHIll tltilizalioll ~lial)i ~ilt loam thl sa 111( soillolllSld in thu raquo1NNling lXPlIilllPllt- was s(rN~n(d and mixed thorol1ghly Half WIIS t11(11 IlwhitlIH(l with a BollIl ion of 1 part or lOllllI1PIltial fOlmddpoundilydtl in~j part or wnlll I(ft (OlINI for l day and Ihl1l mixd slcml timCs daily until t ill rOllIltld(h~()f a dilipaINl Thl olhI half WIIS uied 1Il1sllIilizld as II olllo 10 tllllp(latlllt tanks tolliaining

Mi1H 0middotmiddotmiddot

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

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15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

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Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

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17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

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~400 100- r

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~ 60 I o320 I 32 Elt txl

260 ~ 70 IAJ U a I~~JJ vi ~ ~ IAJ ~ ~ 60 ~ ~ ~ I- I o 50 o i 111

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o 16 19 20 21 22 23 244 5 6 7 6 9 10 II 12 7 6 ) 10 II 12 13 14 15 16 17 ~

ltl DAYS AFTER PLANT ING tj

~JGum a-Seedling emergence audbJight development of Sudan grass resulting from seed inoculated with Collctot-chmn uralllfnicQlll1n amI lliullted in sterilized soil at dlfterent temperatures

7 ANlHHACXOSB OF CEREALS AND GRASSES

EFFECT OF SOIL ilOISTURE AND TEiIPERATURE

Sudan grass seedlings developed disease at temperatures from 16deg 103ampdeg C Soil moistlll(~ levels of 35 and 50 percent satumtion showed little cliflerence in disease development so datu were combined in figure 3 lypicitl seedling bUght den~lopecl Itt Hio but emergence was so pOOL ill the controls that this temperature was omitted Disshyease development ttnd host ltlevelopment (as measured by mte of e~nelgenc~ and in(r~HSe in plant heigh~) were both direct~y proporshytlOllal to lI(I(I1S(S 111 tempemtute dUllIlg the short duratwn of the experiment IIj lUll seedllllg blight howevetmiddot was pmcticttlly the same at all temperatures lIsed~

100

II 90 STtRIL- f-- STERILIZEO-IZED

eo I- DRY r- shy 70 _~T_I-

middotTmiddotmiddot x oJ

0 60 I- - i=-- bullbullbullbullbull UIltSTERILIZEO

oJ ~o -lt

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30 l- Ishy

20 i- Ishy

10 i- Ishy

0 -- _L- shy 20 24 28 32 STERILIZATION SOIL MOISTURE TEMPERATUREIC)

tJGlm 4-Efitet of oil 1lli1 iin tion soil 1JIoiitl1r( nllli 1l1II11ern fIIlC llpon the sC(ity oC IIl1thlll(II0se 011 ~ultlnll rus f(gtcdlillS

EFFpoundCT OF SOIf STEHILIZ ITIO SOIL IOISTeHE )0 TE~lPEItATUHE

c(onlt1 expeliJllelltin whieh stp)iliz((l and IInstelilizel1 soils were used showCli im pOllant di tl(l(lleeH ill lUsease lesponse to environshyment rnstCri liZId a nlt1 sleam-steli Iizeti ~[jami silt loams WCLe used nt two 1ll0istllLP ](pls (middotw and liO plr(ent sa(lIl11tion) and at temshyperatm( from W to a~ C at4-degree intela Is Half of each pot was plllnt(ld with ino(ulaled and half with ullino(ulateltl seed as pr(ious expetillHHts hall shown that the Jungns did not sprclHI rapidl thlOugh thl soil The plnntins were made lfalth 2 19+i

bull whcn light condit ions fa )1(1d a stHrdy nOlletiolated sedling (lOcI01)shymen rhe reml(s ntt iurnmarizlltlill figure ck

The investigations ith stlrilizNI and 1I11sllrilized soillen~ale(l that nnothel ftlctOl ioi I mi(loilorn fune ioned in the dcyelopment of anshy

8 IECHNICAL BULLE1IN 1005 U S DEPT OI~ AGRICULTUllE

thracnose on the undelglOllllll seedling tisswcs Apparently both soil temperature and moisture lnflllelHed the development of the soil mishyClOilOrH with a resulting indirect eflect on OolletotJichwn [Jlaminishy(oZlUn HIld disease development tlS shown by the contrast ill disease reaction in the stelilized lnclllnstelilized soils (fig 4) As in the preshyvious experiment the oveL-IlU eUect of teinpellltllle was not significant in sterilized soil In lInsterilizecl soil however disease developmcnt was less at low tempelatures than nt 33deg O Ample Soilllloistllle reshyduced disease incidence thlc tillles as H)uch in the Plps(~n(e of the soil mieloflom asin sl(lilizlel soil In moist ullsterilized soil them waR a low Ieel of diRtaSe at all templ1abnes clue apparently to the antagshyonistic action of soU microfoltl whtteas in dry soil the soil 111icroshyflom weremiddot in(leasingl inellecti( at himiddotrJt ttmplIaimes Apparently diSlase-hJlribiti ng biological factltHIe~ponded both to telll peratul(s and to 1Il0istule ill the uusteri Iizec1 oi 1

Alexopoulos (1) found that Actinomy((s spp ranged fLom strong inhibitors to noninhibitolfi of O flloeospolioides Penz Leben and Keitt (15) follnd that O fllrunini(olUin was inhibited by Rtloptomyccs sp AJthol1gh the evic1ell(e pnsenled in the 1)Jeslnt blllletin indicated that soil mielofl01lt played all importilnt lole in the development of the seedJj~lg cli)eas( of Sudall gltlss (lllsed by O rJIClmini(olum the lesults W(Ie 11IconduSlc

ANIHltCNOS~ D~VELOPiIE~T ox RYE SEELgtLJlXCS IN THE Cn~ENlIOUSE

The relation of elldlOlllllent to tlw delloplllent of the seedling phases of tllthla(lIosc 01 Ie was inetigatecl in a manner similtlL to that J(poried pound01 SlIdan glilS _ dill(pn( leSpOIlHe of host and parashysite to soil tempelutuIe waS lxplcteil as Iye seedlings elmelop best at low templlatules 10 elllpllahlll eli(H of rye seeellings were jnshy(stigated ulldel dif)elent h~ht (ol1clitiOIlS SClies A was grown in Apdl alld)lay Il17 lIndlr good light and long days series B was grown ill ])e((lIliJel 1fH7 dllling a doudy shOLt-day peliod

The llav(s of c1is(asPl] lye seedlings dpwlopec1 a Haccid conditioll followed by (rlolosis wlllJl in the thinl 01 10ll1Ih INLI stage amI subshysequent bUghtillg UI)(I(I (ondilionsfllolahlt fol (lisea5( declopment Neelosis of tlw IOCI1I0cC inte)nocles and selllinal LOOt5 caused these above-glound sympton)s Spdnr and Willltl IY( wPIe both sllseeptibh to the imlal(s of UoUrtotlictum (iltlmini(olulII fJom Ie Tlte san)( ryeisolatl o HIll palhog(llwas us(d in all (x]leliIlIPnts middotith In

EFFECT ov n[PIHAJCIIE SOIL STEHIJIZATJOX AND LIGHT

S(lies ~ WHi )OWn ill stHIll-HiC)ilizelt1 anltlunsteiliicd soil under fa orablp ] ight (oJl(li [iousbullplil ant1 )layIH7 The soil tempclashyllIJes llsedmngetl fJolll H to H C at middot1deg inlenals wit11 the ail temshypela tu Il hpId with i n bgt of the soi I t l1l1 pNai lle a t all but the HO soil telllshypcmtuIp at hiel) the air t(lllll)atu)( was 1UO Only one lank was used Ht ~8deg ilnd 3~o and data foe thcse i(Ill))(IJatUllH aJ( not included Steall1-stIilizcd lllid uJlRt(Iilize(L )[inmi silt loam ele llscd to COJl1shypalC he inflmncts of the soil mi(toflollL on fhl development of the

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A~lHnACNOSE OF m~HEALS ANIgt GHASSES 9

disease at dincrellt tempelltttlLcs Soil moisturil gtas mainbtined at it level favoIable pound01 good plant growth The results Ilre summarized in (i(rme 5 it

s~il tcnpemtUlps infhlCIIltecl the dwelopmcllt of anthracnose in rye scedlings The soil micloflola in the llllsterllized soil modified the temperature response as shown in Sudnr gmss In this series gtown during the spling und(l good) ight ltoll(litions no disease tlmeloped ill the rye eelllings at 8deg soil tCllIpclnflllc and 16deg 0 ail temperature ill either the terilizcd 01 ullsterilizld soil ~t HO soil and 16deg nil tClllshypellltllLe It lIloderute level 0 f disease dceloped in the seril izetl soil alld but little in the lInstelilized soil At Wo and auol seltlling ([amagn WIIS S(lrein the sterilized soil with It disemie illttx of about 1)0 In IllUilNilizet soil Ih( ([isllIsl illlI(IISNI gradllally with It lisein telllshyp(lIltULe At ~Ho and 32deg sOll1e pr(~ltlI1ergence ulighting or tho scedshylings OCClIIIcd ill both stlliliz(d and III1SUIilizp(l SOl

DAYS ArTER PLNTINC

IOOJ~_-Z-7__~Z~J___~20-_~1~ IOO~~0-_--=3~l__~2~4---poundL-----Li

0 90

00

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~ ~ GO fiO

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_oll~----i6-----~2~O----~24 oL8------1~2----~6~----~20~--~24 SOH fC-IIPCRoTURc(-C) SOIL T(UPCRATURr(middotC)

1IlJIIt~ jo-~Ihp illlhllI1(I of iilJll tlIII1Wrllilllp Roil SICIilizatioll nllt light 011 llldllll~ hlight of 111 (III1c(1 h Colcoridlllm I(IIIlIiIOIIlIl A RIPl1illg~ grol1 ill Rlpnllh~tlIiliz(lt1 nlld IIIIHttIillzp( l1illl1i silt loalll ill Sprillg limIer good light ((lIuliliolls i II 1lIItllillg rtl11 III fOIlIIalllh~II(lltlIillzld lllltlImilIl1izpt Miallli silt Imlill in illtlI IIl1dll IJOor light COIllIitiIIIIl

SlrilS n Was TOWll in Jormaldl~hy(l(-~t(liliztd soil tllldcr 1IIlfaomshyblolight lOIHlitloIlS lgtl(PlIIlJll (Il(fJanualY 1H-7-1H FOllIlaldehyde ~t(Li1izati(l1 was slibsi iluHd for Silalll Btelilizationin 01(1(1 too ledlHC thn ehnnges ill physi(al and (1tlIlieaI [HopPIIieR of Ill soil that lemlt (11)111 SitHIll tltilizalioll ~lial)i ~ilt loam thl sa 111( soillolllSld in thu raquo1NNling lXPlIilllPllt- was s(rN~n(d and mixed thorol1ghly Half WIIS t11(11 IlwhitlIH(l with a BollIl ion of 1 part or lOllllI1PIltial fOlmddpoundilydtl in~j part or wnlll I(ft (OlINI for l day and Ihl1l mixd slcml timCs daily until t ill rOllIltld(h~()f a dilipaINl Thl olhI half WIIS uied 1Il1sllIilizld as II olllo 10 tllllp(latlllt tanks tolliaining

Mi1H 0middotmiddotmiddot

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

7 ANlHHACXOSB OF CEREALS AND GRASSES

EFFECT OF SOIL ilOISTURE AND TEiIPERATURE

Sudan grass seedlings developed disease at temperatures from 16deg 103ampdeg C Soil moistlll(~ levels of 35 and 50 percent satumtion showed little cliflerence in disease development so datu were combined in figure 3 lypicitl seedling bUght den~lopecl Itt Hio but emergence was so pOOL ill the controls that this temperature was omitted Disshyease development ttnd host ltlevelopment (as measured by mte of e~nelgenc~ and in(r~HSe in plant heigh~) were both direct~y proporshytlOllal to lI(I(I1S(S 111 tempemtute dUllIlg the short duratwn of the experiment IIj lUll seedllllg blight howevetmiddot was pmcticttlly the same at all temperatures lIsed~

100

II 90 STtRIL- f-- STERILIZEO-IZED

eo I- DRY r- shy 70 _~T_I-

middotTmiddotmiddot x oJ

0 60 I- - i=-- bullbullbullbullbull UIltSTERILIZEO

oJ ~o -lt

bull oJ o 40 I- shy

30 l- Ishy

20 i- Ishy

10 i- Ishy

0 -- _L- shy 20 24 28 32 STERILIZATION SOIL MOISTURE TEMPERATUREIC)

tJGlm 4-Efitet of oil 1lli1 iin tion soil 1JIoiitl1r( nllli 1l1II11ern fIIlC llpon the sC(ity oC IIl1thlll(II0se 011 ~ultlnll rus f(gtcdlillS

EFFpoundCT OF SOIf STEHILIZ ITIO SOIL IOISTeHE )0 TE~lPEItATUHE

c(onlt1 expeliJllelltin whieh stp)iliz((l and IInstelilizel1 soils were used showCli im pOllant di tl(l(lleeH ill lUsease lesponse to environshyment rnstCri liZId a nlt1 sleam-steli Iizeti ~[jami silt loams WCLe used nt two 1ll0istllLP ](pls (middotw and liO plr(ent sa(lIl11tion) and at temshyperatm( from W to a~ C at4-degree intela Is Half of each pot was plllnt(ld with ino(ulaled and half with ullino(ulateltl seed as pr(ious expetillHHts hall shown that the Jungns did not sprclHI rapidl thlOugh thl soil The plnntins were made lfalth 2 19+i

bull whcn light condit ions fa )1(1d a stHrdy nOlletiolated sedling (lOcI01)shymen rhe reml(s ntt iurnmarizlltlill figure ck

The investigations ith stlrilizNI and 1I11sllrilized soillen~ale(l that nnothel ftlctOl ioi I mi(loilorn fune ioned in the dcyelopment of anshy

8 IECHNICAL BULLE1IN 1005 U S DEPT OI~ AGRICULTUllE

thracnose on the undelglOllllll seedling tisswcs Apparently both soil temperature and moisture lnflllelHed the development of the soil mishyClOilOrH with a resulting indirect eflect on OolletotJichwn [Jlaminishy(oZlUn HIld disease development tlS shown by the contrast ill disease reaction in the stelilized lnclllnstelilized soils (fig 4) As in the preshyvious experiment the oveL-IlU eUect of teinpellltllle was not significant in sterilized soil In lInsterilizecl soil however disease developmcnt was less at low tempelatures than nt 33deg O Ample Soilllloistllle reshyduced disease incidence thlc tillles as H)uch in the Plps(~n(e of the soil mieloflom asin sl(lilizlel soil In moist ullsterilized soil them waR a low Ieel of diRtaSe at all templ1abnes clue apparently to the antagshyonistic action of soU microfoltl whtteas in dry soil the soil 111icroshyflom weremiddot in(leasingl inellecti( at himiddotrJt ttmplIaimes Apparently diSlase-hJlribiti ng biological factltHIe~ponded both to telll peratul(s and to 1Il0istule ill the uusteri Iizec1 oi 1

Alexopoulos (1) found that Actinomy((s spp ranged fLom strong inhibitors to noninhibitolfi of O flloeospolioides Penz Leben and Keitt (15) follnd that O fllrunini(olUin was inhibited by Rtloptomyccs sp AJthol1gh the evic1ell(e pnsenled in the 1)Jeslnt blllletin indicated that soil mielofl01lt played all importilnt lole in the development of the seedJj~lg cli)eas( of Sudall gltlss (lllsed by O rJIClmini(olum the lesults W(Ie 11IconduSlc

ANIHltCNOS~ D~VELOPiIE~T ox RYE SEELgtLJlXCS IN THE Cn~ENlIOUSE

The relation of elldlOlllllent to tlw delloplllent of the seedling phases of tllthla(lIosc 01 Ie was inetigatecl in a manner similtlL to that J(poried pound01 SlIdan glilS _ dill(pn( leSpOIlHe of host and parashysite to soil tempelutuIe waS lxplcteil as Iye seedlings elmelop best at low templlatules 10 elllpllahlll eli(H of rye seeellings were jnshy(stigated ulldel dif)elent h~ht (ol1clitiOIlS SClies A was grown in Apdl alld)lay Il17 lIndlr good light and long days series B was grown ill ])e((lIliJel 1fH7 dllling a doudy shOLt-day peliod

The llav(s of c1is(asPl] lye seedlings dpwlopec1 a Haccid conditioll followed by (rlolosis wlllJl in the thinl 01 10ll1Ih INLI stage amI subshysequent bUghtillg UI)(I(I (ondilionsfllolahlt fol (lisea5( declopment Neelosis of tlw IOCI1I0cC inte)nocles and selllinal LOOt5 caused these above-glound sympton)s Spdnr and Willltl IY( wPIe both sllseeptibh to the imlal(s of UoUrtotlictum (iltlmini(olulII fJom Ie Tlte san)( ryeisolatl o HIll palhog(llwas us(d in all (x]leliIlIPnts middotith In

EFFECT ov n[PIHAJCIIE SOIL STEHIJIZATJOX AND LIGHT

S(lies ~ WHi )OWn ill stHIll-HiC)ilizelt1 anltlunsteiliicd soil under fa orablp ] ight (oJl(li [iousbullplil ant1 )layIH7 The soil tempclashyllIJes llsedmngetl fJolll H to H C at middot1deg inlenals wit11 the ail temshypela tu Il hpId with i n bgt of the soi I t l1l1 pNai lle a t all but the HO soil telllshypcmtuIp at hiel) the air t(lllll)atu)( was 1UO Only one lank was used Ht ~8deg ilnd 3~o and data foe thcse i(Ill))(IJatUllH aJ( not included Steall1-stIilizcd lllid uJlRt(Iilize(L )[inmi silt loam ele llscd to COJl1shypalC he inflmncts of the soil mi(toflollL on fhl development of the

bull

bull

bull

bull

bull

bull

A~lHnACNOSE OF m~HEALS ANIgt GHASSES 9

disease at dincrellt tempelltttlLcs Soil moisturil gtas mainbtined at it level favoIable pound01 good plant growth The results Ilre summarized in (i(rme 5 it

s~il tcnpemtUlps infhlCIIltecl the dwelopmcllt of anthracnose in rye scedlings The soil micloflola in the llllsterllized soil modified the temperature response as shown in Sudnr gmss In this series gtown during the spling und(l good) ight ltoll(litions no disease tlmeloped ill the rye eelllings at 8deg soil tCllIpclnflllc and 16deg 0 ail temperature ill either the terilizcd 01 ullsterilizld soil ~t HO soil and 16deg nil tClllshypellltllLe It lIloderute level 0 f disease dceloped in the seril izetl soil alld but little in the lInstelilized soil At Wo and auol seltlling ([amagn WIIS S(lrein the sterilized soil with It disemie illttx of about 1)0 In IllUilNilizet soil Ih( ([isllIsl illlI(IISNI gradllally with It lisein telllshyp(lIltULe At ~Ho and 32deg sOll1e pr(~ltlI1ergence ulighting or tho scedshylings OCClIIIcd ill both stlliliz(d and III1SUIilizp(l SOl

DAYS ArTER PLNTINC

IOOJ~_-Z-7__~Z~J___~20-_~1~ IOO~~0-_--=3~l__~2~4---poundL-----Li

0 90

00

~ 10

~ ~ GO fiO

70

X ~ ~~ ~too

UtoULHutUi -0

~ 0 OJ 30 JO e tl I

I0 I I

A 10 B I

t

_oll~----i6-----~2~O----~24 oL8------1~2----~6~----~20~--~24 SOH fC-IIPCRoTURc(-C) SOIL T(UPCRATURr(middotC)

1IlJIIt~ jo-~Ihp illlhllI1(I of iilJll tlIII1Wrllilllp Roil SICIilizatioll nllt light 011 llldllll~ hlight of 111 (III1c(1 h Colcoridlllm I(IIIlIiIOIIlIl A RIPl1illg~ grol1 ill Rlpnllh~tlIiliz(lt1 nlld IIIIHttIillzp( l1illl1i silt loalll ill Sprillg limIer good light ((lIuliliolls i II 1lIItllillg rtl11 III fOIlIIalllh~II(lltlIillzld lllltlImilIl1izpt Miallli silt Imlill in illtlI IIl1dll IJOor light COIllIitiIIIIl

SlrilS n Was TOWll in Jormaldl~hy(l(-~t(liliztd soil tllldcr 1IIlfaomshyblolight lOIHlitloIlS lgtl(PlIIlJll (Il(fJanualY 1H-7-1H FOllIlaldehyde ~t(Li1izati(l1 was slibsi iluHd for Silalll Btelilizationin 01(1(1 too ledlHC thn ehnnges ill physi(al and (1tlIlieaI [HopPIIieR of Ill soil that lemlt (11)111 SitHIll tltilizalioll ~lial)i ~ilt loam thl sa 111( soillolllSld in thu raquo1NNling lXPlIilllPllt- was s(rN~n(d and mixed thorol1ghly Half WIIS t11(11 IlwhitlIH(l with a BollIl ion of 1 part or lOllllI1PIltial fOlmddpoundilydtl in~j part or wnlll I(ft (OlINI for l day and Ihl1l mixd slcml timCs daily until t ill rOllIltld(h~()f a dilipaINl Thl olhI half WIIS uied 1Il1sllIilizld as II olllo 10 tllllp(latlllt tanks tolliaining

Mi1H 0middotmiddotmiddot

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

8 IECHNICAL BULLE1IN 1005 U S DEPT OI~ AGRICULTUllE

thracnose on the undelglOllllll seedling tisswcs Apparently both soil temperature and moisture lnflllelHed the development of the soil mishyClOilOrH with a resulting indirect eflect on OolletotJichwn [Jlaminishy(oZlUn HIld disease development tlS shown by the contrast ill disease reaction in the stelilized lnclllnstelilized soils (fig 4) As in the preshyvious experiment the oveL-IlU eUect of teinpellltllle was not significant in sterilized soil In lInsterilizecl soil however disease developmcnt was less at low tempelatures than nt 33deg O Ample Soilllloistllle reshyduced disease incidence thlc tillles as H)uch in the Plps(~n(e of the soil mieloflom asin sl(lilizlel soil In moist ullsterilized soil them waR a low Ieel of diRtaSe at all templ1abnes clue apparently to the antagshyonistic action of soU microfoltl whtteas in dry soil the soil 111icroshyflom weremiddot in(leasingl inellecti( at himiddotrJt ttmplIaimes Apparently diSlase-hJlribiti ng biological factltHIe~ponded both to telll peratul(s and to 1Il0istule ill the uusteri Iizec1 oi 1

Alexopoulos (1) found that Actinomy((s spp ranged fLom strong inhibitors to noninhibitolfi of O flloeospolioides Penz Leben and Keitt (15) follnd that O fllrunini(olUin was inhibited by Rtloptomyccs sp AJthol1gh the evic1ell(e pnsenled in the 1)Jeslnt blllletin indicated that soil mielofl01lt played all importilnt lole in the development of the seedJj~lg cli)eas( of Sudall gltlss (lllsed by O rJIClmini(olum the lesults W(Ie 11IconduSlc

ANIHltCNOS~ D~VELOPiIE~T ox RYE SEELgtLJlXCS IN THE Cn~ENlIOUSE

The relation of elldlOlllllent to tlw delloplllent of the seedling phases of tllthla(lIosc 01 Ie was inetigatecl in a manner similtlL to that J(poried pound01 SlIdan glilS _ dill(pn( leSpOIlHe of host and parashysite to soil tempelutuIe waS lxplcteil as Iye seedlings elmelop best at low templlatules 10 elllpllahlll eli(H of rye seeellings were jnshy(stigated ulldel dif)elent h~ht (ol1clitiOIlS SClies A was grown in Apdl alld)lay Il17 lIndlr good light and long days series B was grown ill ])e((lIliJel 1fH7 dllling a doudy shOLt-day peliod

The llav(s of c1is(asPl] lye seedlings dpwlopec1 a Haccid conditioll followed by (rlolosis wlllJl in the thinl 01 10ll1Ih INLI stage amI subshysequent bUghtillg UI)(I(I (ondilionsfllolahlt fol (lisea5( declopment Neelosis of tlw IOCI1I0cC inte)nocles and selllinal LOOt5 caused these above-glound sympton)s Spdnr and Willltl IY( wPIe both sllseeptibh to the imlal(s of UoUrtotlictum (iltlmini(olulII fJom Ie Tlte san)( ryeisolatl o HIll palhog(llwas us(d in all (x]leliIlIPnts middotith In

EFFECT ov n[PIHAJCIIE SOIL STEHIJIZATJOX AND LIGHT

S(lies ~ WHi )OWn ill stHIll-HiC)ilizelt1 anltlunsteiliicd soil under fa orablp ] ight (oJl(li [iousbullplil ant1 )layIH7 The soil tempclashyllIJes llsedmngetl fJolll H to H C at middot1deg inlenals wit11 the ail temshypela tu Il hpId with i n bgt of the soi I t l1l1 pNai lle a t all but the HO soil telllshypcmtuIp at hiel) the air t(lllll)atu)( was 1UO Only one lank was used Ht ~8deg ilnd 3~o and data foe thcse i(Ill))(IJatUllH aJ( not included Steall1-stIilizcd lllid uJlRt(Iilize(L )[inmi silt loam ele llscd to COJl1shypalC he inflmncts of the soil mi(toflollL on fhl development of the

bull

bull

bull

bull

bull

bull

A~lHnACNOSE OF m~HEALS ANIgt GHASSES 9

disease at dincrellt tempelltttlLcs Soil moisturil gtas mainbtined at it level favoIable pound01 good plant growth The results Ilre summarized in (i(rme 5 it

s~il tcnpemtUlps infhlCIIltecl the dwelopmcllt of anthracnose in rye scedlings The soil micloflola in the llllsterllized soil modified the temperature response as shown in Sudnr gmss In this series gtown during the spling und(l good) ight ltoll(litions no disease tlmeloped ill the rye eelllings at 8deg soil tCllIpclnflllc and 16deg 0 ail temperature ill either the terilizcd 01 ullsterilizld soil ~t HO soil and 16deg nil tClllshypellltllLe It lIloderute level 0 f disease dceloped in the seril izetl soil alld but little in the lInstelilized soil At Wo and auol seltlling ([amagn WIIS S(lrein the sterilized soil with It disemie illttx of about 1)0 In IllUilNilizet soil Ih( ([isllIsl illlI(IISNI gradllally with It lisein telllshyp(lIltULe At ~Ho and 32deg sOll1e pr(~ltlI1ergence ulighting or tho scedshylings OCClIIIcd ill both stlliliz(d and III1SUIilizp(l SOl

DAYS ArTER PLNTINC

IOOJ~_-Z-7__~Z~J___~20-_~1~ IOO~~0-_--=3~l__~2~4---poundL-----Li

0 90

00

~ 10

~ ~ GO fiO

70

X ~ ~~ ~too

UtoULHutUi -0

~ 0 OJ 30 JO e tl I

I0 I I

A 10 B I

t

_oll~----i6-----~2~O----~24 oL8------1~2----~6~----~20~--~24 SOH fC-IIPCRoTURc(-C) SOIL T(UPCRATURr(middotC)

1IlJIIt~ jo-~Ihp illlhllI1(I of iilJll tlIII1Wrllilllp Roil SICIilizatioll nllt light 011 llldllll~ hlight of 111 (III1c(1 h Colcoridlllm I(IIIlIiIOIIlIl A RIPl1illg~ grol1 ill Rlpnllh~tlIiliz(lt1 nlld IIIIHttIillzp( l1illl1i silt loalll ill Sprillg limIer good light ((lIuliliolls i II 1lIItllillg rtl11 III fOIlIIalllh~II(lltlIillzld lllltlImilIl1izpt Miallli silt Imlill in illtlI IIl1dll IJOor light COIllIitiIIIIl

SlrilS n Was TOWll in Jormaldl~hy(l(-~t(liliztd soil tllldcr 1IIlfaomshyblolight lOIHlitloIlS lgtl(PlIIlJll (Il(fJanualY 1H-7-1H FOllIlaldehyde ~t(Li1izati(l1 was slibsi iluHd for Silalll Btelilizationin 01(1(1 too ledlHC thn ehnnges ill physi(al and (1tlIlieaI [HopPIIieR of Ill soil that lemlt (11)111 SitHIll tltilizalioll ~lial)i ~ilt loam thl sa 111( soillolllSld in thu raquo1NNling lXPlIilllPllt- was s(rN~n(d and mixed thorol1ghly Half WIIS t11(11 IlwhitlIH(l with a BollIl ion of 1 part or lOllllI1PIltial fOlmddpoundilydtl in~j part or wnlll I(ft (OlINI for l day and Ihl1l mixd slcml timCs daily until t ill rOllIltld(h~()f a dilipaINl Thl olhI half WIIS uied 1Il1sllIilizld as II olllo 10 tllllp(latlllt tanks tolliaining

Mi1H 0middotmiddotmiddot

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

bull

bull

bull

A~lHnACNOSE OF m~HEALS ANIgt GHASSES 9

disease at dincrellt tempelltttlLcs Soil moisturil gtas mainbtined at it level favoIable pound01 good plant growth The results Ilre summarized in (i(rme 5 it

s~il tcnpemtUlps infhlCIIltecl the dwelopmcllt of anthracnose in rye scedlings The soil micloflola in the llllsterllized soil modified the temperature response as shown in Sudnr gmss In this series gtown during the spling und(l good) ight ltoll(litions no disease tlmeloped ill the rye eelllings at 8deg soil tCllIpclnflllc and 16deg 0 ail temperature ill either the terilizcd 01 ullsterilizld soil ~t HO soil and 16deg nil tClllshypellltllLe It lIloderute level 0 f disease dceloped in the seril izetl soil alld but little in the lInstelilized soil At Wo and auol seltlling ([amagn WIIS S(lrein the sterilized soil with It disemie illttx of about 1)0 In IllUilNilizet soil Ih( ([isllIsl illlI(IISNI gradllally with It lisein telllshyp(lIltULe At ~Ho and 32deg sOll1e pr(~ltlI1ergence ulighting or tho scedshylings OCClIIIcd ill both stlliliz(d and III1SUIilizp(l SOl

DAYS ArTER PLNTINC

IOOJ~_-Z-7__~Z~J___~20-_~1~ IOO~~0-_--=3~l__~2~4---poundL-----Li

0 90

00

~ 10

~ ~ GO fiO

70

X ~ ~~ ~too

UtoULHutUi -0

~ 0 OJ 30 JO e tl I

I0 I I

A 10 B I

t

_oll~----i6-----~2~O----~24 oL8------1~2----~6~----~20~--~24 SOH fC-IIPCRoTURc(-C) SOIL T(UPCRATURr(middotC)

1IlJIIt~ jo-~Ihp illlhllI1(I of iilJll tlIII1Wrllilllp Roil SICIilizatioll nllt light 011 llldllll~ hlight of 111 (III1c(1 h Colcoridlllm I(IIIlIiIOIIlIl A RIPl1illg~ grol1 ill Rlpnllh~tlIiliz(lt1 nlld IIIIHttIillzp( l1illl1i silt loalll ill Sprillg limIer good light ((lIuliliolls i II 1lIItllillg rtl11 III fOIlIIalllh~II(lltlIillzld lllltlImilIl1izpt Miallli silt Imlill in illtlI IIl1dll IJOor light COIllIitiIIIIl

SlrilS n Was TOWll in Jormaldl~hy(l(-~t(liliztd soil tllldcr 1IIlfaomshyblolight lOIHlitloIlS lgtl(PlIIlJll (Il(fJanualY 1H-7-1H FOllIlaldehyde ~t(Li1izati(l1 was slibsi iluHd for Silalll Btelilizationin 01(1(1 too ledlHC thn ehnnges ill physi(al and (1tlIlieaI [HopPIIieR of Ill soil that lemlt (11)111 SitHIll tltilizalioll ~lial)i ~ilt loam thl sa 111( soillolllSld in thu raquo1NNling lXPlIilllPllt- was s(rN~n(d and mixed thorol1ghly Half WIIS t11(11 IlwhitlIH(l with a BollIl ion of 1 part or lOllllI1PIltial fOlmddpoundilydtl in~j part or wnlll I(ft (OlINI for l day and Ihl1l mixd slcml timCs daily until t ill rOllIltld(h~()f a dilipaINl Thl olhI half WIIS uied 1Il1sllIilizld as II olllo 10 tllllp(latlllt tanks tolliaining

Mi1H 0middotmiddotmiddot

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

10 r~ClL~ICAL BULLElIN 1005) U S DEPl Ol~ AGHICUWUHE

14 pots each of unsteli1ized alld fOlllIaltlehyde-heated soils were lleltl at each temperature (SO 12deg 16deg Wo 21degC)~ with the uir tempeltshyture 10 higher than the soil tempemture in each case except the first in which the ail temperature was Smiddot higher than the soil Seed inocushylation of the rye gmms waS llsed rhe resulting daht are summarized ill figure 5 B

In series B disease was increased by high temperatures and sterilized soil as in series A The clifferellcesill fa VOL of unste1ilized soil were smaller howevel and disease was not prcelited at So C rhe harmful effects of steam st(lil ization upon the physietl-chemiea I propel ies of the soil weakened the host resulting 1nsome inclenslCl blighting The difference betweell disease leels in steam-slelmiddotilized alld unsterilizl~d soil thus included both this harmful ellett on soil propeltips lind th( effect of the soilmiCloora FOllnnldehy(le-stelilized soilinltlicahld It

lesser depressing effect of soil microf1ollt upon (liseae development The contlllst between the disease pleSlnt espedally at SO lind 12deg in the two sClicsis interpretcd as cvidence that host stls(epUbility was inshycreased by low light intensity nnd short day length

gFFgCT OF DIFFEHgiT SOILS

Miami silt loam and three Plainfield salld~ wHh difl)Len clopping histories but typicnllYo soils (IC tI~ed ill till invesligation of the inshyfluence of soillYPl all(l (LOP Slqtllnce 011 s(eltlling blight of lye HIllf of each of these soils a~ ~telilized with formaldehyde and the other haH was unstedlize(l Soil inoculation with coniditt Iwd mY(llin ~lown 011 eultl1lc solution was el1lployed Moisturc WIS maintnined by cstimate at L leel Jaomble fOl plant growth Diseasc was reshycOlc1ed as pcrccntage of blighted ~l(llillgs The rcsults am sumshylJ1llrized in fig-ull G

~ lowl ]((1 of (lisenc hlltid(Il(c was obtainc(l from the soil inocushylation than flllln s(pd ill()(ulatioll but the 1(81I1t8 W(Ie l~~(nlially (0111shypamble Dilflse denloplIlllIi tlloppcd gm(ually bl]OW Ho C in both stelilizP(l and ullsteliliz((J -oils The ratio of seedling hlightin sterishy1ized soil to that illl1flstclilized soil was32 to ~2 perCcnt for the Itvernge of thl(( tcmpemtlllls The (l(elopn1llIt of seeclling blight was nshyf1l1el1(ed by the (litllIpl1t soil (fig fj) The lnoclllge (lis(Hse Ic(l of the folll soils ral1g()lt1 ftom 3( 10 ~) pCl(middot(nt when sl~li1 iz(d and from 20 to la penen inlhe IlnSltIi1izNI oils The diffelCnees in chellliC1l1 and physieal PlOl)(Iti(ls of Ihes(1 soils apparently did not infllllnce disease deelopment eli Ieelly as 1I1I1(h as thli ndi Ilet ele(t of t]w respective soil mlCloflolU on the pathogell

ATIRAC~OSE DEnLOP~rE~T Oi Sugt GHASS i() SIHIG tVI IN TilE FIELD

Fi(lc1lxp(rinllnts in(lll(lillg c1ill(I(nt ltlaip of plan illg were 11111(1(

to che(k th 1(1SlrltS obtninC(J in thp glNlIliOllSI and to dctermine the Cfle(t of allthlHel1oe Oil yiClds of JOlllge and gmin

Oi SI)X GHmiddotSS

Field pIHlltins or lInillOltrlnltd und inO(lrlal(d )((1(101 Sudan grass WClp rnndl ill llHi llld llmiddotIToll till rniplsity of YIis(onsin Exppdshyl11entalllnlm ~radi)()n OIl ~lianli silt loam oJ l1Iollell1l( flmiddottlilitY

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

bull

bull

bull

ANlHHACNQSE OF CEREALS AND GRASSES

In 1946 rows 1 foot Itpalt antI 4 feet long were planted in four replications on five dates In 1947 It quantity of seed calculated as 35 pounds per acre was sown in 14-foot rows 1 foot apart three inocllshylated and three contlolrows iti ench of three replicates

Observutions of sbmd dis(lIlse development and yield were made Many plants escaped seedling blight in tho field but were visibly stuuted DIy-weight forage yields of an enrly lnd l late cutting WOle taken to determine the combined effect of loss of stand und stuntshyiug upon yielil

40r-----------------------------~ _ STERILIZED ~ NOT STERILIZED

~30 tshyz w u ex w Q ~

t-J

~20 oJ III

C)

z i a w w CII

10

l(lllm U-Ael~II_t perCPlltnlc o( sccdlllll lllight ill ryc growlI III llllinlieiti slIlId (NoS 1 nllll I) IIml Miami Hilt lollm (No) llIlliterlllzed IIml sterilized with fOllIl1lhlehYIlc 1IIHlinoculllieti wilh GOllforiet11n UIImillicollIII

Disease dlw~opedhom the inoculated seed at nll dtl(s of planting Ilntllesultcd in ll(u(ed shmds and w(lIklnNI slll(Uings The Ilvemge rednction in stand due to inocula ion was 23 PCIPIII Inoculated rows WUIO (~vit1cnt ilom CIl1(Ig(IHC to filerillg by the wilhl (l stunted disshycolored nnd gellclally w(ak(ncd condition of the plants (fig 7) SurvivIng plants gratlllally recovcrlltl alld the diff(lonCll in appeushylnce between inoculated and conltollows lessened appreciubly as the Bellson l)Logll~-sed Diflclences ill yield were due Il1Hlllly to the weukshy

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

12 11(1[1(1 IllLLETI lO()i t DEIT OF lillI(TLmiddotITHI~

bull

1middotmiddotIHl- I [lllIIPllIlllt I IlIllhlIIIIIIN III -lItllllI ~III ((tI Ii 1Ig (OIIlPIIIillll

or 11J1IIIoW~ IIlIill1I1atld III II nil I IIIIIIIIIII[O illHIIII1IId II) ill nllIIHIl shyilg 1pHall

IllIll plnllt 1I1ltl Iplaltlt lIUtlt of dillptl piant n 111 a [0 n bull11(1middot IXIlIIt till Imiddot(tlllld IHnd Yilltl lintn flOIIl tltl lin plalltillg dll I 1 II IJ Iii nlld Illll 11111 1J 17 1I1I [olidtilllt1 alld ltO1I glllllitilally ill Ii II 11 Yilld (II tll IllIll [ 1dlllld 11 lpd illOtlIlat iOIl III 111 Ia TIIlIad 1I11IIlIIlltI t) I till dI-lllll plalll lI I ill Ha()1l lltltlllld a illdilltllll Iltl [ollllat ill llIlIp ipllI of tltl (olltlol Hllti illtH11111111I ~lIdll11 lll at t It I t I) Illll ing 1It Till Itil1t PIIshy[lIIII1 or illilllilill I(ullill 110111 lld illClIltllllioll Ill IlHllp (11( 11111 111111 01Ild ill lOlllllllIIiti lipid Ill -lIdHll UIH )alllllIl -Ipd 1IIItIIillll ill -lId111 UIa Ita hllll 1(IHlltld fllqlllntly (ltiltPII (l (IIlIltd 1I1lt 111 Ii lld iIolll (l(()Iia litit 01) JImiddot(middotIII inll(tioll -lldlilll ill 1111 illll tlIpllIlly j lit illlPlllttl1Hl t1~1I11 n OUIIt or Ilimiddot IIlal illlHlIllllll ttld dipilliliatiull I Ihl IlIlho(11 tl) tltP folingl Oil lti11 tlmlI i tII( ill 01111 YllIl

laquo[lleI plallILIl Ill iIHHlilnllti 1Ilt IIllilloltllnlld -PIill In 11( JIlldl 1111 tltl t Itini it TIill [nlllI tlllll ~[llioll Oil ~ra ) illld [llf7 Tltp 1ld lin pltlllldlI tIll 1lIlt or II 1J1dlll~ IHI iIp ill 10 j 111[ lOll lIlIl I Ill II I HPHIt TliIPI llItlllld IIlld tllllP il]()lillltld J()

illlllth Ill fill l(ltlilnlill)] 1[1 Ollll ill lltllill pllllltillg tlltiul rUlli IIpJimiddottlioll ill till [ItlIlld 11 IPtillllitlll ill 1lllti dill 1( illfllUittioll rllIld rill I It I Ilu pltlltillg III Lilt It illtlllIlnttd Ill lIt di- bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

13

bull

bull

bull

AN1HUACNOSE Ol~ CEHEALS AND GUASSES

100

90 SUDAN GRASS

80

70 0 UJ 1 060 u 0

UJ 50 ()

laquoIshyz UJ 40 0 0 W 0

30

20

10

0 1ST 2ND EAfLV LATE EARLY LATE

CUTTINGS PLANTING DATES

llOlJltl~ S-B1Yctt (If stlll IlloculatiOIl with (oUltolioIII f1(lIl1illicoIIli 011 yleltls of 8ullllll g1lISS II lid rye

tinguished OlHiiy fLom the control Iowsin till scc(lling stuge by the reduced (IowthlInd ] ighler cololedtolillC of the plants

The di~eflsed plunts in the two dat(s of plnnting showcd It

0

COlltlllst inlCCOlIY soon attll till(lling Jhose in ihn fhst plantillg lCcovcled whereas thos in the Sl(Ollll planting Llmaincd stunted thlongholt the glowing sellson In the (ltlller plilliting Ispc~iully the ~IisCllscd plllnts devclopcd It norlllal color subsequcnt to cstabltshment of COlOlllllloots In lho first planting- the height of thl plants WIIS similal to the control wholells those of the lllhl planting wcm 3 inches shorter lilhwing wns 1(dmNI considelllbly in the inoculaNlows of the second planting in contrllst with only a slight l(duetion in the filst No diifcnmcc in date 01 matulity 1l00illClNtSe in lodging was obsolved between uninoCIIshylntecl rnd inoculated rows of llitllll plulIting Total plnnt wlli~ht aod yield of glllin wele lowered si~niicantlY by the inoClllations m both dates of pltlllting as shown inhgulc 8

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

14 TECHNICAL BULLETIN 1005 U S DEPT OF AGRICULTURE

The field experiment demonstrated a marked decrease in yield reshysulting largely from early damage to the seminal root system The greater 10cS that oc~urred in the late-spring planting corroborated the greenhouse findings of more damage at higher temperatures Typical acervuli and stromata of Oolletot1ich~tm gml11Jinicolmiddottm appeared in abundance on the culms of the late planting It was evident under these conditions that anthracnose of rye caused severe damage to the seminal root system ana crOW11 with a r~sulting reduction in plant yield

DISCUSSION

Early observers associated anthracnose of cereals and grasses with host maturity This group of hosts matured as summer and higher temperatures progressed OoZZetoMmiddoticllJltlh gmminicolu1llJ is It highshytemperature organism Inoculation experinents (38142127) with seedlings hLve demonstrated that senescence cannot be considered a lequisite for parasitism by this pathogen The common association of symptoms of anthracnose and maturation is believed caused at least in part by the influence of temperature upon the fungus In contrast to this group of cold-tolerant hosts the S01ghwm spp suffered severely at the height of their vegetative activity and no association with matshyuration was noted Temperature relations of the host and parasite play an important part in timing disease development The higher heat requirements of isolates from Smmiddotglmm spp was interpreted as an adaptation of parasite to host

rhe influence of environment upon the severity of the seedling disease was less marked in Sudall gras t1lan in lmiddotye rhe total deshyvelopment of cUseae in Sudan grass seedlings was not influenced appreciably by temperature whereas in rye low temperatures greatly redllceel or eliminated the disease These differences in response were attributed largely to temperature requirements of the two hosts The vegetative stage of rye was flwored by cool temperatures while Sudan glllss was retarded by low temperatures The temperature requireshylllents of host and pathogen were opposed in rye and synchronized in Sudan grass Suchw grass seedlings were blighted at all conditiolls studied wheteas rye seedlings suffered little at 8deg to 12deg C

Apparently antagonism by the soilmicroflora lessened the severity of diseaSE development in all experiments where sterilized soil was compared with unsterilized soil In Sudan grass ample soilmoistnre was of greater benefit in unsteriHzed soil than in sterilized soil and the difference between sterilized and un sterilized soil was greater at low temperatures Studies in formaldehyde-sterilized soil with rye subshystantiate these conclusions but indicate that steam sterilization exagshygerated the apparent role of microflora by reducing host vigor and reSIstance

Loss of stand was less severe in the field than in greenhouse tests but experiments showed that even though few seedlings were actually killed the seedling disease resulted in material reduction in yield Usually the fungus was restricted to subcrown parts of surviving plants thus the damage to the seminal root system was apparently responsible for most of the loss The first cutting of Sudan grass was damaged more than the second demonstratinO the partial recovery of diseased plants as the season pLogressed (oZletotlichltln grami11ishy

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

15 ANTHRACNOSE OF CEREALS AND GRASSES

bull (]olltml infected the semlulliroot system and seedling axis and the inshyfection rcsulte(~ in severe loss in yie~d Root-pruning experiments of Sallahs (fJO) SImmonds (23) and Sllnmonds and Sallans (24) demonshystratcd the value of the semiual root system of grasses in subsequent plant dcvelopmcnt Sanford (21) and Rosen (18) presented evidence that anthracnose was capable of inflicting serious losses on oats when attacking in the early stages of plant developmcnt

SUMMARY

Oolletot7ickltm gmminicoZllIn was found to bc a high-temperature orglmism with thc optimum rate of mycelial development at 28deg C A partial adaptation of fungus to host was expressed in the greater heat requlIements of isolatos f1om SVIgh1l1n spp

Temperature had little influence upon the final severity of seedling disease of Sudan grllss but relatively low temperaturer reduced seedshy1jug dislnse in rye

The soil micro(lollt ex~rtec1 an antagonistic effect upon the pathogen its reflected ill disease development Soil type apparently influen~a the severiLy of anthracnose development on roots and lower internodes of rye indirectly through the action of microflola

Yields of rye and Sudan grass were reduced by anthracnose mainly through the destruction of the seminalloot system and damage to the seedUng axis below the coronal nodes

PATHOLOGICAL HISTOLOGY OF ANTHRACNOSE

bull Thc pathological histology of antlmtuosc in Sudan grass and in rye was investigated Thc two hosts differed in both seedling morphology and physiology In rye the intelllode above the coleoptilar node elonshygated whereas in Sudan grass the interllode above the scutellar node llongated Hye seedlings developed best at cool temperatnres (8deg to l~o C) and Sudan grass at relatively high tcmperatUlcs (24deg) rhe development of anthracnose upon both seedling types was similar despite these morphological and physiological differences Sanford (f31) studied thc pathological histology of anthracnose on oats Boening and middotWallner (3) that of corn and Winter (27) that of wheat The development ofthe seedlinO phases of anthracnose on Sudan grass auilrye as reported in this bulletin was found to be similar insofar as the seedlings were comparable

DISEASE DEVELOPMENT AND HISTOLOGY

SUDAN GRASS SEEDLINGS

bull

Sudan grass seedlings grown from seed inoculated with Oolletotrishychwn glaminicolmn were stunted and wilted and eventually many were blighted A ]ocalnecrosis of the elongating internodes severed the plumule from the seed and the seminal root system The necrotic area was blackened covered by setose acervuE and extended various distances up toward the coleoptilar node The margin of the necrotic area was reddish and the transition from necrotic to apparently 11ealthy tissue rather alrupt Acervuli usually were present at the base of the coleoptile These were It source of primary inoculum to

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

16 TECHNIOAL BULLETIN 1005) U S DEPT OF AGRICUI11URE

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

17 ANlHRACXOSE Ol CEHEALS AXD GHASBEg

initiate the loliage phase of alllllla(llo~e A similar llltlosis of adshy

bull Yentitiolls [oots o(clIlLed less frequelltly

GrellIhollse alld field expllillllnt dcmonstlate(l the (alm(ity of seedlings to lecoer by the rapid deelopment of (oronal 100ts Tlwse roots wtre infected less extemi(ly and slllrotial lIlaSSl dcn(opet 011 thelll ehieny at 01 aboe the soil sudaee Foliage legions (1elgt10ped ta 11) and (onl illutll when weathel (ond ilion lI( fa OIable

Piglllentation in the 8udan glHss stllliied(Olllplitll1 two (lasses 1(middot(1 alld tall each (olltrolled by gllIttil iudOIS (OIlIIIlCIeial Sudall lJass hfling the reddish pigment lNIIIioll to injulilgt was Cl1IplOYNllol (his phase or the work Suda II glass with tall pigllHlIl d i1Il( ill sylnptorns at least illsofar as pigmlntation was (OIllLIIlltI Slldlillgs with rotted advltlItitiolls and semillal Ioots Ol thc Ioo gtysll1lI (ut 011 by intCtIlOdllllesiolls le(L Cl[llalld tht Iwalthy piallt ill yield whieh aglCNl with tllp illllgtstigatiolls by Sal1ut (O) SiI1IlOlll[ (JJ) alHI Sil1llllOlHb alld Sallalls tJ4) 011 tIll inqHlItflmp Of liIe llllillfll 1001 ytelll bull Themiddot dleloplHlnt of till fllllgUgt in till iIo-t lisSlIlS W(lS -tudip( ill

(ntbt(hkd alld fr((~-iIalld ((ion~ S(diolls tnillld with Sa [rani II alld fast gT((n ga( good difllI(ntiatiOIl ot tile JlIl1glli a-I(II (IS or (he iIost IlSPOIll to OIl mthogln ln-ta imd -lli iOIl-PI( liSP la 1g-lly to tudy hot Ipa(lioll PholollliCLogmpils 11( lIHd to il1l1stmll pat hologieal h isl ology

bull Sldions of the IiIS intellI0lt1( frolll IIl1illadpd whitl in(lIllo(1al

tisslle thl()llgh the Ild tmll-ition ZOIll into ill( bla(k IIl(lOli( a((IIIshylus-lwaling Ilgion Iolld nsolll(llat (ollsistlnt pat (PIU of pathologishy(a I hitololY rll1oli~h to l(d~lish gUlIlllysubstnIl(l 11gt jll(slnI ill till xy lelll y(SS(s abo( t hl a la 0 t 11l(IOSIS ()I 1l il d IIIH( () I t Ill til lgU

as la rOlnd by HOlning and nlll1l1 (I) in ((1111 11 alllolvllOU dlposit of Sillli1lL (0101 and staining it IJIilliall1 1(1 with saflanin applan(llilst in till ((11 Ia I1- nlllllatlI lillld tilt illilI(CIlulal spaClS both in allall(( of thp 1ll(pliulIl llJd ill thc palatiti~pd area of tilL (orllX (rig II 1) Tlli appaLC1l1 host Ipad ion was IOlali~(l1 lith lapid tlanitiol1 to nOLllIallolti(ti ((Ib Edl(I(OIl and (Inajal (11)

imiddotIltnomiddot 1 Ill tIOIlgtP of lIjoll IIIIoWI1 lml (IIIlInl 1001 tiltl- or SlIdlll )Ia alld I~ to (()I((lIitllill illllIl1inicolIl1 1 1111 1111 (10 lt(Iioll of iiI ill[(IIIO([ allo( till (ltyl(ltOIlIIY lnd ill nil ldin Sudlll )11 pll Ii II) llOWill) Ihl n )lIlIllik (Iloil ill IIII illl1(llulII PlI o IIII (011()( 1111 1111 ill 11111( I thl xyl(11i 11 II (11 s IIrpllal e till iUII4I1S in lilt ln(odllllli llId IlliIlIII(al Ih (1111))(11 XIIII 1(11 111 I X7(0) nI 1111 (otI 110 ((1(111 (lr linl intpll)(lp ill n llnIIII altlIk(d SUIl1I )Ia (pdlin llIlWillg llHlIHIII h~Jlhlf Illn 1i111I(1 0( ~1II111 iI (JllIsil i II I Ill 0111 [1 I rUII)Il IMIII IllIrioll or Ih( (lIlIolillllIi llIti )lPIkI((l (II J laquo(tll(( i()11 01 til )10111111 11111(11 (hIIIHl alld phl11Il (() pllI)~ill) I 111111 1 Ih X~III1 nltI (() allll [(1111-III (I) dly(IIIII11 011 11ll IJlillllllIi~ Ix middot1111 ( 1I JIlI lit t Ill -(Iioll of (tI1I 1001 of IllltlllP Suiall )Ia plallt ~Io11 ill il( lipId sltill~ p1Iinl illnliull IIf (IIIIi1 111 lrtpl (iintP~lIlitJlI r Iii IIIIIX tllll rUII(al IlIlrill tIlIIII1t Io~ tltl IlIdO((PllIIi 1III and iOIi(~Il (III Willi 1Il1t1IOIiS ill llIplllp h)phlll plIIr[llioll lit lilt illnll li1lIlllftIaI Wall I lit (lIlilltllllIi (I) )~~IU) D II [Jarr 111(1lt- Itioll 01 iiI illllIIl(ld of ~1I1l1l11 gLas lIoilll

bull th( (iIri(l1 (Ill all 110111(1111( st(llIdar~ Illt 1111111111 IHI tllal fUIIItloll II a hllllill to fllllgU- ill lioll I jlO) H t PH Il til II I ~11f illn (II 111111 i 1IIIIIIIIh illo tIll ([popl i 111 III Hlp (If lalllilll a II 1I1d I)l ((I 11 i II) -howshyill~ ~IIIn I il1raltillll h rhi 11I1I)IIS 11111 plllill It S(lIIII ot lh ~I(lll 11(( ~ middot1-101

(iIj I ~omiddot 1

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

18 1ECHNICAL BULLETL~ 1005 J U S DEPT OF AGRICUUfURE

found Il similar red material in red rot of sugarcane Protoplasts enshyclosed within thes~ reddened cell walls appeared to remain fUllctiomtl for some time Later as fungus development proglessed the protoshyplasts colllpsed as dId also the cell walls At thiS later stage of necrosis cavities in the cortex extendin~ from the endodelmis toward the epidennis were characteristic The lesion at this stage comprised the necrotic segment the all~a of fungus advance between the cells Ilnd the outer zone of host tissue that showed reaction From this stage on the cortex apparently ollered little resistance and the fungus ramishyfication was mpid (fig 0 B)

Frequently aCelltl i welc orlllccl on the epidermis lhe frequency of large necrotic areas in the cort ita I pa renchyma cell~ near the endoshydermis suggested that the fungus ad anced most rapidly in the inner Iortical pllrenchyma Limited l~l(tratioll through the cell walls of the enclodermis amL peticycl( Was found ill association with these cortical lesions when adjacent to t11e~Jlem vessels (fig 0 A)

The cell walls of both the endodcIl11is and pericycle otlered a partia1 morphological barriet to fungus adnlHcpoundgt into the centml stele (fig 9 0) When penetmtion occuLTed neaL the xylem e-~els the myceshyliulll ellteled theSl~ cells by direct penetration through the tangential walls Eidently digestion through these walls was dillicult as secshytions showed llUmelOll5 partial pllletIiLtions ill coutlast to the few that were completed Once therung11s was thlough these barriers the mycelium advanced thlough the palenchyma Penetration of the xylem vessels appalently oCclIlIed llss commonly but once within those esse Is the myCelium udnll1Ced longitudinally but did not plug lhe vessels Deposition of tIl( gumlike ~Hmolphous substance in the xylem vessels oc(uLIed V(IY (llllIllOllly (fil( 0 A) The phloem tissue was parasitizell finally and when penetltlted vas completely oelTlin (fig 0 B)

Cortical lesions ol(ulred neal the (otyledonaLY node followed by agglessie ilwasion of the node Ilwasion of the node applltently WlS not so (oml11on in Sudan )ass as in Iye The histology of this type of inasiOIl in le is dtcIile(l later ul1der rve

Many Sudan glaSi scedlings hall become je(shlblished by the deelshyOplllent of coronal root btlore the tissue ilwasion desclibed had cut otf translocation bltweell the s(gt(lling alltl the seminal Ioots fhis oft(n OCluIIell un(ltl field conditiOliJogt S((dling growth and total yidd ofomge Wn~ Iedueld eyen though lecO(gtIy of the plants was not tleltyed greatly

Rotting of the seminal roots was I(s S((I( in Sudan gaSi than in Iye ~d(lntitioug roots of Sudan glH alising from the (otyledonalY int(lllode frequently W(Ie attackpd 01 killld Fungus deelopment in tltc roots was simihu to that dPRlribp(l 101 tlw fint il1telllode 11 the stelt~ of the intplllO(Je was free of fllllllS and the cOltical lesions spalsP the (l(l-entitiousloot was lot infected due to the plotection of lllbelinlike rnatelia1s d(()()-1ited in the (OltlX alound the root rupture (fig D D)

fiues of a plant alllad) SlWI(I tlieaSNl pspltcially at thc cotrleshydonalY node (Ie pel1pj mtp(J at olltlI IOlatiol1s with 110 ploduetioll of gumlike matelinl in lithll tll( tOltpX 01 wl(1lI ess(middotls The resistshyante or the (lll(lo(]plmis and pPIjeYlh ttppal~ll1tly was IlS (lppllltlelli upon the physiological condition of the host than was the cortex

bull

bull

bull

19 ANrHRACNOSamp OF CEREALS AND GRASSES

although the corticlll tissues were invaded Over the entire range of

bull environmental conditions illvestigated Blighting 0pound the SUdl~ll grll~S seedli~lg usuall)~ oeclItTed jf ~he fungus l11vIHled the crown prll110 nll lilli Entran(e 1I1tO these tIssues was flom the lower seedling int(tllo(e into the coleoptilar node Ol~ by penushytmtioll through the base of the (oleoptile The COlt(X of this nodal Itgion and the coleoptile wcre inIl(lNl with little indication of host tissue reaction as des(liLed for the sub(Iownillte~llode The coleopshytile and (orti(a1 tissuls WlIe ramified by a dark-walled shott-celled inter- ftnd intmNl1ula1 II1Y(Pliulll with nbul1c1ant development of acelshyYldi 011 the SlIdacc The lcgiom of difTel(lntiating llolles and intershynodes and the prinOIdiulll of till primal (111111 (Ie invaded and parlisitized (fig 10 A-e)

ItYE SEEDLIS

bull

The devploplIIPllt of the disease and pathological histology in rye (ifTlIed sOIll(what flom thnt ~i(11 101 SlIdan gass ~ee(llillgs of rye glowlI from liNd inmldutl( with Oolictolrictu71lJ [Jlaminicoln1lt were ~Iltyish g1PI II Hllntt~d and wilted 01 blighted titll the Recond 01

th i ld pa f d(nlop~(1 8(p(1 in~s iIO II 110111 inoClIlafetl seed in steri Ie soil htld at 1(jdeg l blightNl wll(11 in the thild to foulth l(af stag( Spring lytfIolll Hl( inoculatld alld sown ill the lipId ell1(lged as (11 as diel tll( control The R(((lling laiel (leelopltl grayill~ yelshylowing al1dHllllltil1~ Lnt finally 1((0(1((1 to a large extlnt as jointing hl~an Sim i la I ll(()(ry of oatH was leported by San~folc1 (31) Eln though the ITl phUlf apparelltly rNonlpd consi((rably aner th( dlnloplIlllIt or th( (olonalroot sysl(1l the yie1lt1 of grain aemg(d W PlI((nt below that of the uninm1I1atpd cOlltrolFi

Tht dHlIOplIHlIt of (he palhoglt11 ill r(latiQIl to host tissues was ~tldild 110111 lIli(IO(OIlll s(dion TIH mallIial was stained with lll fllnin a ndfat gTP(n 01 ola ngl (l a lid mOllllted j n ba lsam For the (Ittail of host Iea(tioll ull(aillld iNlions (Ie compacd with those luiIwd

)[rllliull1 uld a((IlIli (If thl fllngus were ablllldant on the pedellr) of llie glLminn[p( klIn(gtls Myecliit dcyelopment was llllgely on the stllfa(p and in tIll epid(llI1a (plls of th peLiealp with little penctlll shylion thloll~h tIl( inlltL lpidllIlUt walls

Inasioll of the yOUilg sll(lling fllpar(gtntly OCIIIlNl after the rupshyIltle of the p(rkarp near the (lleloping ~l11bryo Blo11 mycelium flfluently was found ill the base of the scutl1llt1l1 and adjacent pntenshylhylla Illar thl s(utellal OL otI((onalY no(le (fig 11 A) Masses of dad pClsi4ing illllL~ and inlla-C(lual my((lia wtIl C0l11111011

i 11 the parPllehYllla aiLjaltlnt to tl1e position h(Ie the sClltelln l tracc ll1lelp(l tht SNlllillg nlsldu axis liLequtlItly the colcolhizn aml 111$( of tlw (ol(oplile wlllinndNl (xtel1sively with a(ervllli deYllshyoped on (1(i r 51 IrtCIS )Iycelin1 i Ilasion j nto the Compltx of 11118shy

tcimosing as(l1lal llllIl(l1ts and gLound pulncl1yma (ol11ptising the loIYedonarmiddot lind ((llp(lptilal Ilot(middot ]l(IlllittNI ilw funlIs to advan(e

bull illt() the slminallOo[s alld into tll( sU)flon inle111o(e frequently reshyslllting in blighting or wilting rlt( OlmatiOI1 of gumlike deposits in the xlel1l ye-sels O((I1I1(d adjacent to and ailoye lh~ illf((fl(l alla and lOrlH~ mYltlli lim ()(llIltcl ill the eslI (fihS fI g and III I)

20 LECHXI(AL BlLLET(X 1005 r S DEPT OF AGRICULTURE

bull

bull

bull

~I

bull

bull

VI r II 11 11 I~t ttllh~ li I bull 1 bull (1 Itidllill (IIIIlilWIIIUII

L lhU~f~P p~ ~Ulll pf of pplLt hliVfl tfl1t~nlll)alfidJu tUot( iH= HtH J-hp t bull ar HH~ fPIUH tit flmiddot It n~ llip fllflll II(HIIPI~ 111 Illt

bull -not iJ I PIr)~ bull tlf~I ~i tH~ iu a utmiddottlllU Itll tIUI_I1 ljmiddotne I bull (lI L(ul c llw Iill~middoti halllt II 10 1111111(1 I lIk IIUllw1l1I1II bull l Ii (1 tcmiddotf~l jhIH bullJ~ urultaf HHh uf a P Pfmiddott(hll~ 1 ~ iJ jllt JUfldpttt~

h~t ~lfil Ii ~~a t~f utUl )-1t~lU th tt aut ttH~r1 iun inu or JIUmiddotuuh~middotlllmiddotj

t(t i~u ~ bldfll~ p~irl(hJua Ul~middotH~ihdiu 11H~ p(nlalmiddot PitJJUlIls u h H i~ I phat ~ h HI Pj~llIltl ~ it-Ill tUIIpflt-ln trIll of (otuJJ1l JJOtlf

11 ~t ~ ( u t tiull H 11111al tmiddottJot ahll plpnlhila tt 1 ur t I1t- ppt

iL~ 1 H~ nit ~AJtlmiddotrn UUltl of tllmiddotmiddot ~nmiddot~_(tlllmiddottt lUHIl fUytmiddotnnu t

alilalil P lb ltl ltIhl iI lah-1 Iii lmiddotttmiddotX - Ill

20 LECHXI(AL BlLLET(X 1005 r S DEPT OF AGRICULTURE

bull

bull

bull

~I

bull

bull

VI r II 11 11 I~t ttllh~ li I bull 1 bull (1 Itidllill (IIIIlilWIIIUII

L lhU~f~P p~ ~Ulll pf of pplLt hliVfl tfl1t~nlll)alfidJu tUot( iH= HtH J-hp t bull ar HH~ fPIUH tit flmiddot It n~ llip fllflll II(HIIPI~ 111 Illt

bull -not iJ I PIr)~ bull tlf~I ~i tH~ iu a utmiddottlllU Itll tIUI_I1 ljmiddotne I bull (lI L(ul c llw Iill~middoti halllt II 10 1111111(1 I lIk IIUllw1l1I1II bull l Ii (1 tcmiddotf~l jhIH bullJ~ urultaf HHh uf a P Pfmiddott(hll~ 1 ~ iJ jllt JUfldpttt~

h~t ~lfil Ii ~~a t~f utUl )-1t~lU th tt aut ttH~r1 iun inu or JIUmiddotuuh~middotlllmiddotj

t(t i~u ~ bldfll~ p~irl(hJua Ul~middotH~ihdiu 11H~ p(nlalmiddot PitJJUlIls u h H i~ I phat ~ h HI Pj~llIltl ~ it-Ill tUIIpflt-ln trIll of (otuJJ1l JJOtlf

11 ~t ~ ( u t tiull H 11111al tmiddottJot ahll plpnlhila tt 1 ur t I1t- ppt

iL~ 1 H~ nit ~AJtlmiddotrn UUltl of tllmiddotmiddot ~nmiddot~_(tlllmiddottt lUHIl fUytmiddotnnu t

alilalil P lb ltl ltIhl iI lah-1 Iii lmiddotttmiddotX - Ill

~I

bull

bull

VI r II 11 11 I~t ttllh~ li I bull 1 bull (1 Itidllill (IIIIlilWIIIUII

L lhU~f~P p~ ~Ulll pf of pplLt hliVfl tfl1t~nlll)alfidJu tUot( iH= HtH J-hp t bull ar HH~ fPIUH tit flmiddot It n~ llip fllflll II(HIIPI~ 111 Illt

bull -not iJ I PIr)~ bull tlf~I ~i tH~ iu a utmiddottlllU Itll tIUI_I1 ljmiddotne I bull (lI L(ul c llw Iill~middoti halllt II 10 1111111(1 I lIk IIUllw1l1I1II bull l Ii (1 tcmiddotf~l jhIH bullJ~ urultaf HHh uf a P Pfmiddott(hll~ 1 ~ iJ jllt JUfldpttt~

h~t ~lfil Ii ~~a t~f utUl )-1t~lU th tt aut ttH~r1 iun inu or JIUmiddotuuh~middotlllmiddotj

t(t i~u ~ bldfll~ p~irl(hJua Ul~middotH~ihdiu 11H~ p(nlalmiddot PitJJUlIls u h H i~ I phat ~ h HI Pj~llIltl ~ it-Ill tUIIpflt-ln trIll of (otuJJ1l JJOtlf

11 ~t ~ ( u t tiull H 11111al tmiddottJot ahll plpnlhila tt 1 ur t I1t- ppt

iL~ 1 H~ nit ~AJtlmiddotrn UUltl of tllmiddotmiddot ~nmiddot~_(tlllmiddottt lUHIl fUytmiddotnnu t

alilalil P lb ltl ltIhl iI lah-1 Iii lmiddotttmiddotX - Ill

22 lECHXICAIJ BeLLETI~ 1005 U S DEPT OF AGRICULTURE

1J1(gt s(miunl roots w(le rotted chipoundIly by mycClilllll adllllcing thlough the s[CI tIorn the infected hypoltotyl ani adjacellt nodal (0111shyppoundx (fi~ 11 It) DCltlllctioll of eminal roots was more extellsi C

III rye thlll ill Sudan grn- In many instarHcR the root coriCx WitS Compalntiely 11( or t1middot(Clium whelell the stele was infected with ntunel(HlS hypha~ 1)1(ent in the large ((ntnll metllxylem essei 1he (ortex of the setnUlid root W(lS Ilppalently proteetecl from the allyanee of th( fungns by thpound suhlIinlike deposits II1Olln( the root ruptures in tIl( tol(odrizu The Jllwelinm ill the (OllCX of th( roots t(ndec1 to dbintlg-rate as d((gtlib(~l by Sanford (i21) in out The IlnHlneclosis or tl( (mi11nlloot lind the spIelld of therungus outwa1d w(re similul to that lepoltNI lw UOll1i11g and Yallnpound (n Selelotial mas lIH d(sedb(d by Vinlcl) (til) illwlwat W(le not obsNTed

Thlt in(Cllloc( (nelosNI wit hin thc coleoptile US rolled chielly by themiddotlI1YtlliuIU ad and nghom thll nodlll (ompllx below Conidia were follI1~d intruellIulillly in 11l(loti( lueHs of the cortlX and stelaI parlll shy(Imll SOllie tI( oli(1((1 ill tht XYlem ve(ls Th( conidia were -lfwt(I lps (uITll1 llld I(BB shlllply-pointed than lhoic fOlmed extelshynall v The gumlikl ttbstanee was nblllHlant in thpound xylem (sseI8 St(l(J Ii llg-S recoelj JIg afttI t 11( r0lI1ll tion 0 f (()lona1 root~ show(d IlsS 1lpid nclVHlleC of (lll llIycelium in tll( uppel pnrt of thi intelHod with dlClopllHllllhi(Oy in t If (ot(Cx Th(~ hyphue l(tween the cells ncljlHlnt to tlil lHaIt Itr time dellopld brown lellni nn I Ilst ing ((lls Both hot I(aetioll and pathog(n 1(P011S(l Sllg(stl(l tim (XI)l(ssion of host Itsistume in (hC int(lllO(lnl tissu(s immldiat(y lPlow the (IOWI1 nd in tIll intlIlla1 U-llIS of thc (lon of the phllltS l((()Y(Iing uftlr (Iown oot (lclopnltnt nypound (NlIin~rs grown in (he gleenhollsP lt1(-tlopld (Olona I roots and tiller huds slo(l han in the lle1ds an(l 1((0middot(1 lilwwip was Iower

Tlln~i()n oC tlll crown U~Sllt of Ise Wu elipfly into the periphery of til(gt ((lIt(X 01 I nl) the lOtHHl IHllelHhyma of the (entml (oronn I )lg-ion (fig U Baud C) TIll (Illlglls (lpeloped a RIIomnlikl nJa of (plls bltWlrt nlld within the ((11 lfi~ 11 C) alh(l thanby n few hypIHl~ n(lIlwing intPIllllnlady u in man othl1 tisslC rhe trallshyltiOIl from iUIHlp( to ollnlldtd ti sSII (I waR nhlupL Thp gum deshyposits in till w-pl- in (ll nOlhs of thl (ron (fig- n D) W(IP not prolol1lHpd u d(~(lilJ(d by B()(Ining fllllt1 TalllHt (J) ill (om ilh tlu fltllptniJlihllllut of tIlI ((JlOllltlloot Syst(lllI nllcl (olldiiiollS fa 01shynhl( 101 tIll (((Iopllwnt of tillP) buds niHI (111m eoHaton fung-us ill(hioll of dw (lOWIl (isslIls WIIS Iilllil(d 10 loertl (optical I(-ion 111 Illt snWloU axis Iml ()((u-innnllOot l(-ionTlw pathogen was w(l1l --iilll (Id fol ill vnioll of tIll bad (( Im t bs 1 P lwl grow i1Ig- (oIH1ii ions Wllt lIufnolubh 01 as tlH planb appIo[lclld maUllit) InonllulIl wn PlotllHpd on lI(Jl and PIllill laf Ili(lll- fell -pt ul to dllt(lopshyi llJ hlYP

Cillulnr to oal pot~ llo 111111 in (liUIIWl(l jill piglll(lIhd malshytrill nlHl bllnlltld to I Ia Yl()I(Jll~d (P11PI oil 11 ith l(PIyttli tpp1op(ld (( dWIUtlri-ti( of tIll di~(a-( 011 ~lIdlin t[nl- lean Spl(lfl(1 of tlll (ulln IHJ(lllll tltl pigllHll(d ~0lH an (oalp(poundIl(P of thegt spot (II( tll1lOI1ll011 On ~OIlH -(middotItd iOll- of Sncim gla- l( 1lOlld t nl( of kiOlI )(lt1lllll TIll Ip-ioll- dlyltloppd ana pnnc1 without mrllginal

bull

bull

bull

23 ANfHRACNOSE OJ CEREALS AND GRASS~S

pigmentation alld frequently coalesced to forllliurge elolligllted neerotshy

bull ilt bleached IllenS with Ilcelnlli scattered OY)1 the lurface Mild Igtigllwntatioll and zonute-type lesiIlS developed in SOIlamp instances FIequcntly the sevellll types of leSIOn ocellllNI on the same tgtlulltS~

Isoiatiolls made from the two types of lesion und leilloclilaLlOns On seedlings did not indicate the existence of two silll ins of the plllllsite as fiLslgt suspected Seedlil1 tCSPOIlSC 1I0eel as Hot considered enlirely leliable for leaf lesion type The cOlllpalativc histololTY of the leSIOns intlicnled the IlUSml(l~ of host rCspomm by pigmelllHtio~ and r(tal(led mycelial ll(inl1lcc in the spteading type of lesion Pigmenshylation lIlllged ftom Ieddish to tan in the selC(fiolls of Sndall gluss ~tlldie(l del)Cndhl 1l1)OIl the faclols fOl l)i o H1lnt IJlesent l~i(Tmented Igt Igt Igt leaf lesIOns were described by Butlet t5) 011 sOIghum

The tntllllte of the Jungus into the ICIles or Sudal1 grass waS not -lwJied in c1dlliL Pelletllltion was dir(ctIy through lheclIticle as reshypOLted by ChowdlJlIlT (8) 101 corn and by EdgCrton lind Ctllnjal (11) COImiddotsugnl(une No gellllluLws WCle found entelillg th Iough stomata or wounds 1lequflIt1y they glcw OVN -tolllHtn fhe germ lllbes elollshygal(d alilfolllINI brown latheL Ilgulal apptcssolia With light-coloLed gelm pores

bull

Themiddot myelium aggl(iratNI in thl lpidellLaJ cells above dislasld tisshyliues Dalk-stnining l1l)(lliulll lkh i1l tored food WtlS fOlmed in the ppid(I~lItd lanIs XUlHCIOUS hypllllP penetltlted OllWtll(Uy thlough till ll)(llImal wails A thin tnmHt dlelopNI b(middotlow till tlltkll and linnlly luptured it ictal oliginated dilelmiddott1y flom hyphae within the lpidellnal (~~lls n~yuCL~ld by EdgCltOll aHl Calajal (11) (figs 12 lJ nnd I) [)) Ihe Hun hyphal tOll11lltLOns between the setne and mycelia mass within the silbt(ntiing (phlcllllal ce1s became darkshyPllld alld ele nppnleJltly of the same horny tonsistcney as thc setae whell mature lind orllwt it firlll IInchorage for the setae 011 the stlOllla Tl1l(onitih were bumpound IIpOll a paliade of short conidiopholes ill a iilOllS matrix lind 1I((~lI11ulated in large 1lImUels Oil the acervulus in lite ab(l(C of hee llloiturl Oil the sudtlec tfigs B B and 1G 0) They wele diseminuted apidly when free watel dilui(ll the matrix Spondatlull Oil the mUlllll UteLltius Rlparllltiy was largely at the lXPCIHiC of 1(ilIlS in thl mYleliulll tiS Ct)llaps(~ in tIl( ndjaeenl host t iisUC was pronounced

Host laction in the spot-type l(sion wHs(ident hy anlIpt tallsishylioll from nc(rotit to Illalrhy llICsophyll tissue sUIlollndillg the lesion (fig 1 1) Vhill I1Nlosis antilIIyeelilllll extend(([ flOl11 lphhIlllis to epidlllI1is in til( Ilion lateral slllend a lpstli(i((1 Adjacent nHiophyll (ells and intlICpllulal spa((s 11( filled with a pigll1llItcd tlmolphoui ubtalltl fOllning a nallow to wide ~Wlll (uttilIg oil the Ilioll The widl hoI thl ZOIH as 111 as the (0101 of the pigmlnt aried with the sttuin of Sudan glnss fhe (letailelICspolll of thl ploloshyIlla~t~ of till llltophyll ~lll was obitlIlC( by (h( (hlIse pigmenta lioll The )Ilncilld l1Notic tislIlof til( Itsioll (lntl[ shrunk to one-tilinl of its original t hiekll(ii Thl smn lIer y(jm (xllnd ing t hr(JuU1 the II((IO 1( a 1(1 i1old some IINTOSIS II nel Jl1ngns 11ll1l1 Ia t lOll Ad)aeent

bull xylelll (-(1 sho((l th(~ tipposition of tilt gumlilw subslalll

J litt oJslIcd lIy Dr D C Rlllitli ill till h1(((lillJ 1IIlS(IY ill the SIlIllIll(r tit H)middotHi

2-1 1Cl-gt(AL BlLLrII-gt 1005 r - Dr ()l~ AliBI(PLlTHB

bull

bull

1middotHIIt 1 lLIltIillll 01 thp (gt11 1111111 or ~Ilal ~III 11111 1111 (die 1lriltllIIl IPIIIIIlIIIIlIll t 1 (middot(t jou ~11l111I 1H~S Ita I h Illh IIIH 10 i II I IItlillld hmiddotjllu hllit hllIlth~ lai IbI1t dltt J 11lIhitillll 1 111 PoIIHmiddot1l1 at ill IUHIiu of 1111 11011 IIPUIlI) lUlIl phIImiddott ti- lI I Ij-III I I 711 N (I ~I lull lit ~lltlllll Il har IhlouoiI )11 tmiddot I ZOIHltlmiddotmiddott111 1Imiddotjl1l1 with a 11(1111 IIf imlmiddotlItnlillll mild Illlmiddotlmiddotthi 111111 PIlIlatiuli 11 llOlh 11Imiddottttmiddotmiddot 1 rjlll ( 1 tr iull or II pn 11 I t 11(111 h1 I~ IH f ( 111) n (Im (illIl lit I bullImH or It )1-( I~ Itaf tllllIlI1I till middotoIII1Nd illlmiddotntlmiddott li~t1t ot Ilsioll I lt middotIU I

25

bull

bull

bull

A~lHRAC~OSJJ OF CEHEATS AX) GRASSES

lllw hist(1logy of the spt~a(1illg-trpe l~sion indicated less host reacshytion (fig 1~ II) Amorphous sllbstlln(~s and pigmentation were less lyident StrOlllatn ill the epidlmis nnd acerYlli on the sudllce ubove dleloPNI 0(1 the Jlelrotic artlI Sttains of t-)u(lall g1llS$ highly resistshyant to the 1lIf spot hlle not been studied in detHil

HVELEAVES

I~eiions on gletll ITe lea Vl de(~loped by rapid lIIycelial SP1~lld I hlough the tissues Hnd neefosii or (piltiellnal HlHlmesophyll cells (fig I ( and fJ) The penetration of tln cuticlt and the estllblisltnlnt of l-itromuta ill the eplderllJal celh WCll similal to that d~seihed for -UlaquoHII glURS N~closis of thl epitllllIIalllnd lllesophyll (els o((lIltcd Iapidly without the (((position of tll( alllorpholls slIhsll1lcCS so proshylIouJlNI in ~Udllll gtaRS Tim walls of the epidetmal (cls collapsed Ulld disinttgla(l~d lupidly ill thl idllit of the strOll1abl and aceluli whkh obs(ult~d thu dNlli1S of the fulIglls-host relationship shown so (Ieady in ~ndllll g1llSS alid Rugalcane (II) StrollluLu and acclvuli llsIIllIy tolllle(l Oil the 5111faee in plIltllclloWS betw~en the VCillS nyc 1(I1(s in th( lIli(lils silldied llC vely susceptible to IIl1thlllcnose III Hlel both lilhl a lid glecll holtSpound (olld i tiom

COHOXAL HOOTS

(01011111 100( ot 01lt1(1 SINllillgS ill thl gleenhonse Hilli of matulC plants ill t 11(1 1ild (1( palasitizlt b the JUllglls Exposed (0101111

tOOtH of -ud11 glaRs slllllings (j to 0 illdllS high wele inlcded by ulIinl i lHltlIl 11111 in R gllllIhoWoe t(st Heell lilies of ~udall glass inshy(Illeling Tift and SWl(t Sudall lestld in thl gllCnhOllSI (Ie SlIS(CPshyt Illlc to ill is tpl 0 fill t((tiOIl Till (Oltex WlIS destlo)ed bllt thc stele was plO[(dld fOISOIlll tillle by the (ndollImis YlIell the fllngns gaillld (llt1am(~ to till st(ll these Joots were (lit otl by a local nC(losis FINIIPJllI lldlings with exposed (olollul roots eollapsed and setose Hllttli Wll( alJlIIHlllllt on 1Ill Ioots and baSI of Ihe (ol(opUt StIOshyIllata ll( fUlInd UpOIl tOlollal roots of matlin plants in the ficld (spteiall) whell they pte (xpose( (ligW) Willttl (27) ceselibed imilal fOIlIlf1tiollsin whCut IOOS StlOllaa wen hllglsl ill thl peshyliplwl of Ih(ls[(lleanc1 fl((IH(ntly fillltl the tissnes between melllxy]em lSSl Is rhe exod(lnlis alltl l11lodpllllis ~Ie flNluently filled with 1lIYl11i uIll -iloll1atie ntassps of lIIcllillln fOllllld Uhin host cells l(nstilllted 1 stlUt Ul(~ nlapteti -for pIestITaliol of the fungus1lIylllilltn

CHilli and leaf sheath illfe((ion 01 the (elitls and glllSRlS llS t11CY apPloneh Illatllrity 11m been It(ogll ize( as t he most (ommon ma nifesshytation of ulIthllllOSe III glIHIal this ilwasioll occnrs late in the dl(lo]lIlWllt of the hosts with IlsS ltii Il(t dalllagl to t-ht (IOp than that illcl1ITed in spl(lling illf((tioll 111 thl l1lnnnial glllSHPS the splead 01 llll fungus into till (I()WIl tislIls in the sCond and thild seasons flcshyltinpnt I (HUld tands to dip out TIll HylllptOllS 01 the tliRemlcin the

25

bull

bull

bull

A~lHRAC~OSJJ OF CEHEATS AX) GRASSES

lllw hist(1logy of the spt~a(1illg-trpe l~sion indicated less host reacshytion (fig 1~ II) Amorphous sllbstlln(~s and pigmentation were less lyident StrOlllatn ill the epidlmis nnd acerYlli on the sudllce ubove dleloPNI 0(1 the Jlelrotic artlI Sttains of t-)u(lall g1llS$ highly resistshyant to the 1lIf spot hlle not been studied in detHil

HVELEAVES

I~eiions on gletll ITe lea Vl de(~loped by rapid lIIycelial SP1~lld I hlough the tissues Hnd neefosii or (piltiellnal HlHlmesophyll cells (fig I ( and fJ) The penetration of tln cuticlt and the estllblisltnlnt of l-itromuta ill the eplderllJal celh WCll similal to that d~seihed for -UlaquoHII glURS N~closis of thl epitllllIIalllnd lllesophyll (els o((lIltcd Iapidly without the (((position of tll( alllorpholls slIhsll1lcCS so proshylIouJlNI in ~Udllll gtaRS Tim walls of the epidetmal (cls collapsed Ulld disinttgla(l~d lupidly ill thl idllit of the strOll1abl and aceluli whkh obs(ult~d thu dNlli1S of the fulIglls-host relationship shown so (Ieady in ~ndllll g1llSS alid Rugalcane (II) StrollluLu and acclvuli llsIIllIy tolllle(l Oil the 5111faee in plIltllclloWS betw~en the VCillS nyc 1(I1(s in th( lIli(lils silldied llC vely susceptible to IIl1thlllcnose III Hlel both lilhl a lid glecll holtSpound (olld i tiom

COHOXAL HOOTS

(01011111 100( ot 01lt1(1 SINllillgS ill thl gleenhonse Hilli of matulC plants ill t 11(1 1ild (1( palasitizlt b the JUllglls Exposed (0101111

tOOtH of -ud11 glaRs slllllings (j to 0 illdllS high wele inlcded by ulIinl i lHltlIl 11111 in R gllllIhoWoe t(st Heell lilies of ~udall glass inshy(Illeling Tift and SWl(t Sudall lestld in thl gllCnhOllSI (Ie SlIS(CPshyt Illlc to ill is tpl 0 fill t((tiOIl Till (Oltex WlIS destlo)ed bllt thc stele was plO[(dld fOISOIlll tillle by the (ndollImis YlIell the fllngns gaillld (llt1am(~ to till st(ll these Joots were (lit otl by a local nC(losis FINIIPJllI lldlings with exposed (olollul roots eollapsed and setose Hllttli Wll( alJlIIHlllllt on 1Ill Ioots and baSI of Ihe (ol(opUt StIOshyIllata ll( fUlInd UpOIl tOlollal roots of matlin plants in the ficld (spteiall) whell they pte (xpose( (ligW) Willttl (27) ceselibed imilal fOIlIlf1tiollsin whCut IOOS StlOllaa wen hllglsl ill thl peshyliplwl of Ih(ls[(lleanc1 fl((IH(ntly fillltl the tissnes between melllxy]em lSSl Is rhe exod(lnlis alltl l11lodpllllis ~Ie flNluently filled with 1lIYl11i uIll -iloll1atie ntassps of lIIcllillln fOllllld Uhin host cells l(nstilllted 1 stlUt Ul(~ nlapteti -for pIestITaliol of the fungus1lIylllilltn

CHilli and leaf sheath illfe((ion 01 the (elitls and glllSRlS llS t11CY apPloneh Illatllrity 11m been It(ogll ize( as t he most (ommon ma nifesshytation of ulIthllllOSe III glIHIal this ilwasioll occnrs late in the dl(lo]lIlWllt of the hosts with IlsS ltii Il(t dalllagl to t-ht (IOp than that illcl1ITed in spl(lling illf((tioll 111 thl l1lnnnial glllSHPS the splead 01 llll fungus into till (I()WIl tislIls in the sCond and thild seasons flcshyltinpnt I (HUld tands to dip out TIll HylllptOllS 01 the tliRemlcin the

26 lECH~lCAL BULLE~LIN 1005 U S DEPl OF AGRICUVlURE

crOWll of orchllrd Orass ale shown in fiOure 11 In all of the OrHSS hosts studied pen~tltltlon into nodal ~nternoc1al) and leaf sl~eath tissues of the nHlturo culm oceulred commonly in the vicinity of the bull nodes Early penetration and parasitism of the noc1al tissues resulted ill premature killing of the culms and shriveling of the caryopses

lenetrution into the epidermal coIls of the leamiddotf sheath was c1ilect Numerous nppressoritt were fotmod on the epidermis of the culm and the closely nppllsseltlinnel epitlellnis of the leaf sheaths Apprcssolitt were less abul1dnnt on the exposed sudnces Masses of mycelium were

bull

FrGum 13-DisCHscll CtUWll of 1I1lturc Sudan grHss growll ill1icil1 from Inoculated $ced Strolllatic masses (8) tIrc eyidcnt on eulm nnd brucc roots ubovc the soil linc (sl) X l~~

formed in the cpidelmal cclls both in the vicinity of the points of pcnetration and where the myceliulIl deyeloped neal the surface nfter ~preadil1g longitudinally through the parenchymatolls tissues The pillenchynut layer below was destroyed (fig 15 A) although usually till fungus clcYelopnllnt was no dNper than this undellying parenshychyma TIH peripheral sclereneltyma eells in culm and leaf sheath tisiue (fig 13l and 11) functioned nogt morphological barriers resultshying in the elongated longitudinal stromatic masses ]n the invaded ltpidClmal (cUs and sparse mycelium in the collapsed ltrenchyma bull lwlow Hypha( p(lIetrated outward through till outer epIdermal cell

bull bull bull

gtZ 1-3 tIl gt n Z o Yl tl

o Ij

c tl ~ tl

~ U2

gtZ )

o )jshym tl U2

fjIGUIU~ H-TiIl(r from 1 ll1uture crown of Daclylis ulomcrata-sliowillg (a) healthy (IJ) diseased (e) dead tillers and laquo(l) old culm base in the progressive destruction of the plant by CollctOilichll7n Ylalll ill icolUIll X 1

t -J

28 lECHNlCAL BtTLLElIX 1005 C S DEP~l OF AGlUCULlUInJ

bull

bull

vHWiU 1-IllIniun of tit( Itaf 1HlIlh and (lilll li-II( Ilr grasHP b~ Coilcf)shyIi(lruln [Iallillicolil I FrlltiHllltl (IO~ ~l(ti(ln 01 1(111 -reallr of IrCIIJII p(ensf showing dCstrl1Ction of narcnchYlllrttous tisRI1( alaI ficlerotial mises and l(cluli (X ]~O) B Inellnllll (It)~ PtUOII o( I~( CUllll -howing invasion r(l-tr-icUli hy IlIPlranieal fiSSlIl (X lO) C a(CITUll1s with (olli(lini lJlIISS hpld in lIIatrix X lO) D liNlil ul prr 11111 (OrrlHItiOll (IIollgh thl p[liclormnl (pLl wall of ~ll(lan glngt (X iiiO) 8 CIO edion UIIollgh I(af sheath of Fellllca c(ltior irollillg lpstrlldi(l1l of llal(lIeh~mntolls tissue fungal stroma in lpidlIlIIal (gt(1 ami (ollllltiol (0 Sl(I( (1 surface (X lUG) bull fo mrfaec yi(w of (pillpllIlis of j(SIIltU rubfl showing darkened pitlikc strucshytlllP (X GG) ( (IOS eclion (Jf (111111 of P(81 I((liia II ell I lIode showing clark in tacellulnr 1I1YClliulll (X 4(0)

29

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

W[tUS 0 and formed the numerous acervuli (fig 15 0) and stromaia that ruptured the cuticle as they enlarged Setae developed from hyphae connected directly with the mycelial mass middotwithin the epidershymal cells (fig 15 D and E)

The nodal tissues of the culm were invaded more extensively than were those of the internodes The fungus developed between and within the cells of the node Hyplml strands going through cell walls connected the clark myceliulIl within the pnrasitized cells (fig 15 G) Masses of dark mycelium formed in these collapsed tissues around the Ilnastomosing vascular elements and extended into the cortex The bundles here as elsewhere were COllll)tllatively resistant MyceshyliUln and deposits of the gumlike substance however frequently were found in the xylem vessels

Invasion of the developing caryopsis and the position of the seedshybOlne i lloculum ere not ill Iestigated

DISCUSSION

Sudan grass and rye were selected as representative plants for these investigations These two crops represent sOll1e major differences in deelopmental anatomy ill the grasses as well as a contrast in the tisshySueS nttacked Ululel field conditions A number of economic l)erennial gmsses were used for compulIson 01 to check certain phases of tho stud Disease development and patllOlogical histology were genshyornlfy sim ilar in these hosts However the establishment of the fungus in the crOWH tissues and the gradual or rapid elimination of stands attN the first year especially where soil fertility has been depleted) were majol phases in the development of the disease in the l)erennial grasses not common to the anllual ones~

Entrance into the host tissue was by the formation of appressoria and dilect penetration as described for variou pecies of the genus OolshyletotJiclntln l)elletratioll usually was into embryonic or young tisshySlles except within the leaf sheath where apparently mature culm and leaf sheath tissues were inmcled Appressoria characteristic of the genu weI( fOlmod in abundance in the areas where penetration OlCIlITNI Not infrequently applessoria formed on the surface of ol([el tissues without penetration ApPlesorialike structures within el11 and in disintegrating tissues functioned chiefly as vegetative restshyi IJir (el Is

)lycelial masses c1eelopec1 espeeinlly within the epidermal cells (ell-wall penetmtion OCCUlTed even in the more resistant tissues snch as the endodetmis and sclelenchyma Hyphal strands extended through the Valls connecting the mycelial masses within the cell lumina alld through the epidermal wall to the acervuli on the surface Myshycelial advallce alld destruction of host tissue occlIlrecl chiefly in the parenchyma Spread in the nodal parenchYI11t caused severe dnmnge

o gdgerton and Carayajal (11) stllslSelt1 the role of pits in cell wnlls in the entrancp of the pound111l)(IIH intmiddoto lIm1 in its exit from the Jot Freql1entl~ pits are IHleut ill ellidtrmnl ((I1H (tig ]5 D ulll B) alld nre illiportant to O ll(llninicolllm In its penetration of rlIntiyely r(gtistant tissues (figs fI 0 and 15 G) A snrface iew of (gtllilt1ermal (ells of Prsllea 1111(( showing the abulldance of pitlike openshyings i8 shown in Jig 15 P

30 lECHNICAL BULLELlN 10051 U S DEPl OF AORlCULlUHE

Two types of leaf lesions occUlTed in Sudan glmiddotttSs-a restricted spot and It genelallesion with indefinite margins The latter type of leslOn was general in rye The pathological histology of the restricted lesion indicated a host reaction fUllctioning as l blurier to fungus spretld in the mesophyll

Host reaction with evident restriction of rapid fungus advance was observed in codex mesophyll and pericycle A gumlike amorshyphous substance was deposited between alld within the cells in advance of the fungus invasion Mycelium of the pathogen accumulated in maSses adjacent to the reacting host tissue lather than advancing rapidly through and between the cells In such tissnes the tlallsition from invaded to healthy tissues was delineated sharply This host respvnse waS mOre pronounced in plants glOwing under environmental conditions favorable for good plant dCcloplllent than when glowing under Ullfavorable en vi LOnll1ents

~

SU~I~(RY

The pathological histology of anthmcnQse of Sudan grass and rye seedlings resulting from inoculated seed was studied These hOits suffered seYeLely when the fundamental parenchyma of the region of the scutelllll 110de 01 the main meristem was parasitized

Penetration into the host was direct The endodermis and peri cycle selTed as partiRl baniers PIior to sporUlation the funglls chalactershyistically massed It l1I)leIi UIll rich in stored food in the epidermal cells

A gUlllllly matelial was dlposited in the xylem vessels of diseased plants ~

PHYSIOLOGICAL SPECIALIZATION IN COLLETOTRICHUM GRAMINrCOLUM

The physiologic specialization of Coll(tol1iciwn glaminicolum is impoltallt from the standpolllts uf crop selluence and of brending for disease- resistance Selby and ~IallllS (12) using spore suspensions obtainNl flOlll infected wheat and enunN kemels as inoculum SIlCshyeelmiddotded in prodllcillg typical symptoms of anthracnose on wheat and em 111( I in the field ~They obtainrcL infection of emmer with the fungus 110111 wheat Chowdhury (8) repolted high infections on sorghum with an isolate frOIl1 com alld 011 COIII with an isolate from sorghum but on 10 middotwid(middotly difterent cmeal and glHsses less disease was plOshy(ltl((lt1 by the isolate fl0111 corn He did not state his criterion of infN-tiol in the tests which wme conducted in the laboratory

Tinter (7) observed e g)lminicolilin as the eause of foot rot of oats wheat barley and ye and stated that the funglls from eaeh was pathogenic upon each of the other hosts aHhol1~h he presented no data Sanioed (21) was Ullable to infect wheat barley 01 flax with the isolate feom otltS Aecorc1ing to Edgerton (10) Carvajal and Bd~erton (fl 11) inoeu]at ions with Physao8jJom furu1J1anensis Speshygazzini ((olleto1icAllIlb(alcat-wn Yent) prodllcedlesions on Sudan grass Johnson gll1SS aIH other smghums although natural infection a~ limited chiefly to sugarcane and Leptochloa jilifolmi8 (Lam) lkflu C lineolct Conln now considered a synonym for C qllminishy(olwl has been reported extegtl1sielr on Soghwn spp especially in the South rhe report by Jones and Teimel (13) of a fungus morshy

bull

bull

bull

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

bull bull bull

gtZ 1-3 tIl gt n Z o Yl tl

o Ij

c tl ~ tl

~ U2

gtZ )

o )jshym tl U2

fjIGUIU~ H-TiIl(r from 1 ll1uture crown of Daclylis ulomcrata-sliowillg (a) healthy (IJ) diseased (e) dead tillers and laquo(l) old culm base in the progressive destruction of the plant by CollctOilichll7n Ylalll ill icolUIll X 1

t -J

28 lECHNlCAL BtTLLElIX 1005 C S DEP~l OF AGlUCULlUInJ

bull

bull

vHWiU 1-IllIniun of tit( Itaf 1HlIlh and (lilll li-II( Ilr grasHP b~ Coilcf)shyIi(lruln [Iallillicolil I FrlltiHllltl (IO~ ~l(ti(ln 01 1(111 -reallr of IrCIIJII p(ensf showing dCstrl1Ction of narcnchYlllrttous tisRI1( alaI ficlerotial mises and l(cluli (X ]~O) B Inellnllll (It)~ PtUOII o( I~( CUllll -howing invasion r(l-tr-icUli hy IlIPlranieal fiSSlIl (X lO) C a(CITUll1s with (olli(lini lJlIISS hpld in lIIatrix X lO) D liNlil ul prr 11111 (OrrlHItiOll (IIollgh thl p[liclormnl (pLl wall of ~ll(lan glngt (X iiiO) 8 CIO edion UIIollgh I(af sheath of Fellllca c(ltior irollillg lpstrlldi(l1l of llal(lIeh~mntolls tissue fungal stroma in lpidlIlIIal (gt(1 ami (ollllltiol (0 Sl(I( (1 surface (X lUG) bull fo mrfaec yi(w of (pillpllIlis of j(SIIltU rubfl showing darkened pitlikc strucshytlllP (X GG) ( (IOS eclion (Jf (111111 of P(81 I((liia II ell I lIode showing clark in tacellulnr 1I1YClliulll (X 4(0)

29

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

W[tUS 0 and formed the numerous acervuli (fig 15 0) and stromaia that ruptured the cuticle as they enlarged Setae developed from hyphae connected directly with the mycelial mass middotwithin the epidershymal cells (fig 15 D and E)

The nodal tissues of the culm were invaded more extensively than were those of the internodes The fungus developed between and within the cells of the node Hyplml strands going through cell walls connected the clark myceliulIl within the pnrasitized cells (fig 15 G) Masses of dark mycelium formed in these collapsed tissues around the Ilnastomosing vascular elements and extended into the cortex The bundles here as elsewhere were COllll)tllatively resistant MyceshyliUln and deposits of the gumlike substance however frequently were found in the xylem vessels

Invasion of the developing caryopsis and the position of the seedshybOlne i lloculum ere not ill Iestigated

DISCUSSION

Sudan grass and rye were selected as representative plants for these investigations These two crops represent sOll1e major differences in deelopmental anatomy ill the grasses as well as a contrast in the tisshySueS nttacked Ululel field conditions A number of economic l)erennial gmsses were used for compulIson 01 to check certain phases of tho stud Disease development and patllOlogical histology were genshyornlfy sim ilar in these hosts However the establishment of the fungus in the crOWH tissues and the gradual or rapid elimination of stands attN the first year especially where soil fertility has been depleted) were majol phases in the development of the disease in the l)erennial grasses not common to the anllual ones~

Entrance into the host tissue was by the formation of appressoria and dilect penetration as described for variou pecies of the genus OolshyletotJiclntln l)elletratioll usually was into embryonic or young tisshySlles except within the leaf sheath where apparently mature culm and leaf sheath tissues were inmcled Appressoria characteristic of the genu weI( fOlmod in abundance in the areas where penetration OlCIlITNI Not infrequently applessoria formed on the surface of ol([el tissues without penetration ApPlesorialike structures within el11 and in disintegrating tissues functioned chiefly as vegetative restshyi IJir (el Is

)lycelial masses c1eelopec1 espeeinlly within the epidermal cells (ell-wall penetmtion OCCUlTed even in the more resistant tissues snch as the endodetmis and sclelenchyma Hyphal strands extended through the Valls connecting the mycelial masses within the cell lumina alld through the epidermal wall to the acervuli on the surface Myshycelial advallce alld destruction of host tissue occlIlrecl chiefly in the parenchyma Spread in the nodal parenchYI11t caused severe dnmnge

o gdgerton and Carayajal (11) stllslSelt1 the role of pits in cell wnlls in the entrancp of the pound111l)(IIH intmiddoto lIm1 in its exit from the Jot Freql1entl~ pits are IHleut ill ellidtrmnl ((I1H (tig ]5 D ulll B) alld nre illiportant to O ll(llninicolllm In its penetration of rlIntiyely r(gtistant tissues (figs fI 0 and 15 G) A snrface iew of (gtllilt1ermal (ells of Prsllea 1111(( showing the abulldance of pitlike openshyings i8 shown in Jig 15 P

30 lECHNICAL BULLELlN 10051 U S DEPl OF AORlCULlUHE

Two types of leaf lesions occUlTed in Sudan glmiddotttSs-a restricted spot and It genelallesion with indefinite margins The latter type of leslOn was general in rye The pathological histology of the restricted lesion indicated a host reaction fUllctioning as l blurier to fungus spretld in the mesophyll

Host reaction with evident restriction of rapid fungus advance was observed in codex mesophyll and pericycle A gumlike amorshyphous substance was deposited between alld within the cells in advance of the fungus invasion Mycelium of the pathogen accumulated in maSses adjacent to the reacting host tissue lather than advancing rapidly through and between the cells In such tissnes the tlallsition from invaded to healthy tissues was delineated sharply This host respvnse waS mOre pronounced in plants glOwing under environmental conditions favorable for good plant dCcloplllent than when glowing under Ullfavorable en vi LOnll1ents

~

SU~I~(RY

The pathological histology of anthmcnQse of Sudan grass and rye seedlings resulting from inoculated seed was studied These hOits suffered seYeLely when the fundamental parenchyma of the region of the scutelllll 110de 01 the main meristem was parasitized

Penetration into the host was direct The endodermis and peri cycle selTed as partiRl baniers PIior to sporUlation the funglls chalactershyistically massed It l1I)leIi UIll rich in stored food in the epidermal cells

A gUlllllly matelial was dlposited in the xylem vessels of diseased plants ~

PHYSIOLOGICAL SPECIALIZATION IN COLLETOTRICHUM GRAMINrCOLUM

The physiologic specialization of Coll(tol1iciwn glaminicolum is impoltallt from the standpolllts uf crop selluence and of brending for disease- resistance Selby and ~IallllS (12) using spore suspensions obtainNl flOlll infected wheat and enunN kemels as inoculum SIlCshyeelmiddotded in prodllcillg typical symptoms of anthracnose on wheat and em 111( I in the field ~They obtainrcL infection of emmer with the fungus 110111 wheat Chowdhury (8) repolted high infections on sorghum with an isolate frOIl1 com alld 011 COIII with an isolate from sorghum but on 10 middotwid(middotly difterent cmeal and glHsses less disease was plOshy(ltl((lt1 by the isolate fl0111 corn He did not state his criterion of infN-tiol in the tests which wme conducted in the laboratory

Tinter (7) observed e g)lminicolilin as the eause of foot rot of oats wheat barley and ye and stated that the funglls from eaeh was pathogenic upon each of the other hosts aHhol1~h he presented no data Sanioed (21) was Ullable to infect wheat barley 01 flax with the isolate feom otltS Aecorc1ing to Edgerton (10) Carvajal and Bd~erton (fl 11) inoeu]at ions with Physao8jJom furu1J1anensis Speshygazzini ((olleto1icAllIlb(alcat-wn Yent) prodllcedlesions on Sudan grass Johnson gll1SS aIH other smghums although natural infection a~ limited chiefly to sugarcane and Leptochloa jilifolmi8 (Lam) lkflu C lineolct Conln now considered a synonym for C qllminishy(olwl has been reported extegtl1sielr on Soghwn spp especially in the South rhe report by Jones and Teimel (13) of a fungus morshy

bull

bull

bull

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

28 lECHNlCAL BtTLLElIX 1005 C S DEP~l OF AGlUCULlUInJ

bull

bull

vHWiU 1-IllIniun of tit( Itaf 1HlIlh and (lilll li-II( Ilr grasHP b~ Coilcf)shyIi(lruln [Iallillicolil I FrlltiHllltl (IO~ ~l(ti(ln 01 1(111 -reallr of IrCIIJII p(ensf showing dCstrl1Ction of narcnchYlllrttous tisRI1( alaI ficlerotial mises and l(cluli (X ]~O) B Inellnllll (It)~ PtUOII o( I~( CUllll -howing invasion r(l-tr-icUli hy IlIPlranieal fiSSlIl (X lO) C a(CITUll1s with (olli(lini lJlIISS hpld in lIIatrix X lO) D liNlil ul prr 11111 (OrrlHItiOll (IIollgh thl p[liclormnl (pLl wall of ~ll(lan glngt (X iiiO) 8 CIO edion UIIollgh I(af sheath of Fellllca c(ltior irollillg lpstrlldi(l1l of llal(lIeh~mntolls tissue fungal stroma in lpidlIlIIal (gt(1 ami (ollllltiol (0 Sl(I( (1 surface (X lUG) bull fo mrfaec yi(w of (pillpllIlis of j(SIIltU rubfl showing darkened pitlikc strucshytlllP (X GG) ( (IOS eclion (Jf (111111 of P(81 I((liia II ell I lIode showing clark in tacellulnr 1I1YClliulll (X 4(0)

29

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

W[tUS 0 and formed the numerous acervuli (fig 15 0) and stromaia that ruptured the cuticle as they enlarged Setae developed from hyphae connected directly with the mycelial mass middotwithin the epidershymal cells (fig 15 D and E)

The nodal tissues of the culm were invaded more extensively than were those of the internodes The fungus developed between and within the cells of the node Hyplml strands going through cell walls connected the clark myceliulIl within the pnrasitized cells (fig 15 G) Masses of dark mycelium formed in these collapsed tissues around the Ilnastomosing vascular elements and extended into the cortex The bundles here as elsewhere were COllll)tllatively resistant MyceshyliUln and deposits of the gumlike substance however frequently were found in the xylem vessels

Invasion of the developing caryopsis and the position of the seedshybOlne i lloculum ere not ill Iestigated

DISCUSSION

Sudan grass and rye were selected as representative plants for these investigations These two crops represent sOll1e major differences in deelopmental anatomy ill the grasses as well as a contrast in the tisshySueS nttacked Ululel field conditions A number of economic l)erennial gmsses were used for compulIson 01 to check certain phases of tho stud Disease development and patllOlogical histology were genshyornlfy sim ilar in these hosts However the establishment of the fungus in the crOWH tissues and the gradual or rapid elimination of stands attN the first year especially where soil fertility has been depleted) were majol phases in the development of the disease in the l)erennial grasses not common to the anllual ones~

Entrance into the host tissue was by the formation of appressoria and dilect penetration as described for variou pecies of the genus OolshyletotJiclntln l)elletratioll usually was into embryonic or young tisshySlles except within the leaf sheath where apparently mature culm and leaf sheath tissues were inmcled Appressoria characteristic of the genu weI( fOlmod in abundance in the areas where penetration OlCIlITNI Not infrequently applessoria formed on the surface of ol([el tissues without penetration ApPlesorialike structures within el11 and in disintegrating tissues functioned chiefly as vegetative restshyi IJir (el Is

)lycelial masses c1eelopec1 espeeinlly within the epidermal cells (ell-wall penetmtion OCCUlTed even in the more resistant tissues snch as the endodetmis and sclelenchyma Hyphal strands extended through the Valls connecting the mycelial masses within the cell lumina alld through the epidermal wall to the acervuli on the surface Myshycelial advallce alld destruction of host tissue occlIlrecl chiefly in the parenchyma Spread in the nodal parenchYI11t caused severe dnmnge

o gdgerton and Carayajal (11) stllslSelt1 the role of pits in cell wnlls in the entrancp of the pound111l)(IIH intmiddoto lIm1 in its exit from the Jot Freql1entl~ pits are IHleut ill ellidtrmnl ((I1H (tig ]5 D ulll B) alld nre illiportant to O ll(llninicolllm In its penetration of rlIntiyely r(gtistant tissues (figs fI 0 and 15 G) A snrface iew of (gtllilt1ermal (ells of Prsllea 1111(( showing the abulldance of pitlike openshyings i8 shown in Jig 15 P

30 lECHNICAL BULLELlN 10051 U S DEPl OF AORlCULlUHE

Two types of leaf lesions occUlTed in Sudan glmiddotttSs-a restricted spot and It genelallesion with indefinite margins The latter type of leslOn was general in rye The pathological histology of the restricted lesion indicated a host reaction fUllctioning as l blurier to fungus spretld in the mesophyll

Host reaction with evident restriction of rapid fungus advance was observed in codex mesophyll and pericycle A gumlike amorshyphous substance was deposited between alld within the cells in advance of the fungus invasion Mycelium of the pathogen accumulated in maSses adjacent to the reacting host tissue lather than advancing rapidly through and between the cells In such tissnes the tlallsition from invaded to healthy tissues was delineated sharply This host respvnse waS mOre pronounced in plants glOwing under environmental conditions favorable for good plant dCcloplllent than when glowing under Ullfavorable en vi LOnll1ents

~

SU~I~(RY

The pathological histology of anthmcnQse of Sudan grass and rye seedlings resulting from inoculated seed was studied These hOits suffered seYeLely when the fundamental parenchyma of the region of the scutelllll 110de 01 the main meristem was parasitized

Penetration into the host was direct The endodermis and peri cycle selTed as partiRl baniers PIior to sporUlation the funglls chalactershyistically massed It l1I)leIi UIll rich in stored food in the epidermal cells

A gUlllllly matelial was dlposited in the xylem vessels of diseased plants ~

PHYSIOLOGICAL SPECIALIZATION IN COLLETOTRICHUM GRAMINrCOLUM

The physiologic specialization of Coll(tol1iciwn glaminicolum is impoltallt from the standpolllts uf crop selluence and of brending for disease- resistance Selby and ~IallllS (12) using spore suspensions obtainNl flOlll infected wheat and enunN kemels as inoculum SIlCshyeelmiddotded in prodllcillg typical symptoms of anthracnose on wheat and em 111( I in the field ~They obtainrcL infection of emmer with the fungus 110111 wheat Chowdhury (8) repolted high infections on sorghum with an isolate frOIl1 com alld 011 COIII with an isolate from sorghum but on 10 middotwid(middotly difterent cmeal and glHsses less disease was plOshy(ltl((lt1 by the isolate fl0111 corn He did not state his criterion of infN-tiol in the tests which wme conducted in the laboratory

Tinter (7) observed e g)lminicolilin as the eause of foot rot of oats wheat barley and ye and stated that the funglls from eaeh was pathogenic upon each of the other hosts aHhol1~h he presented no data Sanioed (21) was Ullable to infect wheat barley 01 flax with the isolate feom otltS Aecorc1ing to Edgerton (10) Carvajal and Bd~erton (fl 11) inoeu]at ions with Physao8jJom furu1J1anensis Speshygazzini ((olleto1icAllIlb(alcat-wn Yent) prodllcedlesions on Sudan grass Johnson gll1SS aIH other smghums although natural infection a~ limited chiefly to sugarcane and Leptochloa jilifolmi8 (Lam) lkflu C lineolct Conln now considered a synonym for C qllminishy(olwl has been reported extegtl1sielr on Soghwn spp especially in the South rhe report by Jones and Teimel (13) of a fungus morshy

bull

bull

bull

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

29

bull

bull

bull

ANTHRACNOSE OF CEREALS AND GRASSES

W[tUS 0 and formed the numerous acervuli (fig 15 0) and stromaia that ruptured the cuticle as they enlarged Setae developed from hyphae connected directly with the mycelial mass middotwithin the epidershymal cells (fig 15 D and E)

The nodal tissues of the culm were invaded more extensively than were those of the internodes The fungus developed between and within the cells of the node Hyplml strands going through cell walls connected the clark myceliulIl within the pnrasitized cells (fig 15 G) Masses of dark mycelium formed in these collapsed tissues around the Ilnastomosing vascular elements and extended into the cortex The bundles here as elsewhere were COllll)tllatively resistant MyceshyliUln and deposits of the gumlike substance however frequently were found in the xylem vessels

Invasion of the developing caryopsis and the position of the seedshybOlne i lloculum ere not ill Iestigated

DISCUSSION

Sudan grass and rye were selected as representative plants for these investigations These two crops represent sOll1e major differences in deelopmental anatomy ill the grasses as well as a contrast in the tisshySueS nttacked Ululel field conditions A number of economic l)erennial gmsses were used for compulIson 01 to check certain phases of tho stud Disease development and patllOlogical histology were genshyornlfy sim ilar in these hosts However the establishment of the fungus in the crOWH tissues and the gradual or rapid elimination of stands attN the first year especially where soil fertility has been depleted) were majol phases in the development of the disease in the l)erennial grasses not common to the anllual ones~

Entrance into the host tissue was by the formation of appressoria and dilect penetration as described for variou pecies of the genus OolshyletotJiclntln l)elletratioll usually was into embryonic or young tisshySlles except within the leaf sheath where apparently mature culm and leaf sheath tissues were inmcled Appressoria characteristic of the genu weI( fOlmod in abundance in the areas where penetration OlCIlITNI Not infrequently applessoria formed on the surface of ol([el tissues without penetration ApPlesorialike structures within el11 and in disintegrating tissues functioned chiefly as vegetative restshyi IJir (el Is

)lycelial masses c1eelopec1 espeeinlly within the epidermal cells (ell-wall penetmtion OCCUlTed even in the more resistant tissues snch as the endodetmis and sclelenchyma Hyphal strands extended through the Valls connecting the mycelial masses within the cell lumina alld through the epidermal wall to the acervuli on the surface Myshycelial advallce alld destruction of host tissue occlIlrecl chiefly in the parenchyma Spread in the nodal parenchYI11t caused severe dnmnge

o gdgerton and Carayajal (11) stllslSelt1 the role of pits in cell wnlls in the entrancp of the pound111l)(IIH intmiddoto lIm1 in its exit from the Jot Freql1entl~ pits are IHleut ill ellidtrmnl ((I1H (tig ]5 D ulll B) alld nre illiportant to O ll(llninicolllm In its penetration of rlIntiyely r(gtistant tissues (figs fI 0 and 15 G) A snrface iew of (gtllilt1ermal (ells of Prsllea 1111(( showing the abulldance of pitlike openshyings i8 shown in Jig 15 P

30 lECHNICAL BULLELlN 10051 U S DEPl OF AORlCULlUHE

Two types of leaf lesions occUlTed in Sudan glmiddotttSs-a restricted spot and It genelallesion with indefinite margins The latter type of leslOn was general in rye The pathological histology of the restricted lesion indicated a host reaction fUllctioning as l blurier to fungus spretld in the mesophyll

Host reaction with evident restriction of rapid fungus advance was observed in codex mesophyll and pericycle A gumlike amorshyphous substance was deposited between alld within the cells in advance of the fungus invasion Mycelium of the pathogen accumulated in maSses adjacent to the reacting host tissue lather than advancing rapidly through and between the cells In such tissnes the tlallsition from invaded to healthy tissues was delineated sharply This host respvnse waS mOre pronounced in plants glOwing under environmental conditions favorable for good plant dCcloplllent than when glowing under Ullfavorable en vi LOnll1ents

~

SU~I~(RY

The pathological histology of anthmcnQse of Sudan grass and rye seedlings resulting from inoculated seed was studied These hOits suffered seYeLely when the fundamental parenchyma of the region of the scutelllll 110de 01 the main meristem was parasitized

Penetration into the host was direct The endodermis and peri cycle selTed as partiRl baniers PIior to sporUlation the funglls chalactershyistically massed It l1I)leIi UIll rich in stored food in the epidermal cells

A gUlllllly matelial was dlposited in the xylem vessels of diseased plants ~

PHYSIOLOGICAL SPECIALIZATION IN COLLETOTRICHUM GRAMINrCOLUM

The physiologic specialization of Coll(tol1iciwn glaminicolum is impoltallt from the standpolllts uf crop selluence and of brending for disease- resistance Selby and ~IallllS (12) using spore suspensions obtainNl flOlll infected wheat and enunN kemels as inoculum SIlCshyeelmiddotded in prodllcillg typical symptoms of anthracnose on wheat and em 111( I in the field ~They obtainrcL infection of emmer with the fungus 110111 wheat Chowdhury (8) repolted high infections on sorghum with an isolate frOIl1 com alld 011 COIII with an isolate from sorghum but on 10 middotwid(middotly difterent cmeal and glHsses less disease was plOshy(ltl((lt1 by the isolate fl0111 corn He did not state his criterion of infN-tiol in the tests which wme conducted in the laboratory

Tinter (7) observed e g)lminicolilin as the eause of foot rot of oats wheat barley and ye and stated that the funglls from eaeh was pathogenic upon each of the other hosts aHhol1~h he presented no data Sanioed (21) was Ullable to infect wheat barley 01 flax with the isolate feom otltS Aecorc1ing to Edgerton (10) Carvajal and Bd~erton (fl 11) inoeu]at ions with Physao8jJom furu1J1anensis Speshygazzini ((olleto1icAllIlb(alcat-wn Yent) prodllcedlesions on Sudan grass Johnson gll1SS aIH other smghums although natural infection a~ limited chiefly to sugarcane and Leptochloa jilifolmi8 (Lam) lkflu C lineolct Conln now considered a synonym for C qllminishy(olwl has been reported extegtl1sielr on Soghwn spp especially in the South rhe report by Jones and Teimel (13) of a fungus morshy

bull

bull

bull

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

30 lECHNICAL BULLELlN 10051 U S DEPl OF AORlCULlUHE

Two types of leaf lesions occUlTed in Sudan glmiddotttSs-a restricted spot and It genelallesion with indefinite margins The latter type of leslOn was general in rye The pathological histology of the restricted lesion indicated a host reaction fUllctioning as l blurier to fungus spretld in the mesophyll

Host reaction with evident restriction of rapid fungus advance was observed in codex mesophyll and pericycle A gumlike amorshyphous substance was deposited between alld within the cells in advance of the fungus invasion Mycelium of the pathogen accumulated in maSses adjacent to the reacting host tissue lather than advancing rapidly through and between the cells In such tissnes the tlallsition from invaded to healthy tissues was delineated sharply This host respvnse waS mOre pronounced in plants glOwing under environmental conditions favorable for good plant dCcloplllent than when glowing under Ullfavorable en vi LOnll1ents

~

SU~I~(RY

The pathological histology of anthmcnQse of Sudan grass and rye seedlings resulting from inoculated seed was studied These hOits suffered seYeLely when the fundamental parenchyma of the region of the scutelllll 110de 01 the main meristem was parasitized

Penetration into the host was direct The endodermis and peri cycle selTed as partiRl baniers PIior to sporUlation the funglls chalactershyistically massed It l1I)leIi UIll rich in stored food in the epidermal cells

A gUlllllly matelial was dlposited in the xylem vessels of diseased plants ~

PHYSIOLOGICAL SPECIALIZATION IN COLLETOTRICHUM GRAMINrCOLUM

The physiologic specialization of Coll(tol1iciwn glaminicolum is impoltallt from the standpolllts uf crop selluence and of brending for disease- resistance Selby and ~IallllS (12) using spore suspensions obtainNl flOlll infected wheat and enunN kemels as inoculum SIlCshyeelmiddotded in prodllcillg typical symptoms of anthracnose on wheat and em 111( I in the field ~They obtainrcL infection of emmer with the fungus 110111 wheat Chowdhury (8) repolted high infections on sorghum with an isolate frOIl1 com alld 011 COIII with an isolate from sorghum but on 10 middotwid(middotly difterent cmeal and glHsses less disease was plOshy(ltl((lt1 by the isolate fl0111 corn He did not state his criterion of infN-tiol in the tests which wme conducted in the laboratory

Tinter (7) observed e g)lminicolilin as the eause of foot rot of oats wheat barley and ye and stated that the funglls from eaeh was pathogenic upon each of the other hosts aHhol1~h he presented no data Sanioed (21) was Ullable to infect wheat barley 01 flax with the isolate feom otltS Aecorc1ing to Edgerton (10) Carvajal and Bd~erton (fl 11) inoeu]at ions with Physao8jJom furu1J1anensis Speshygazzini ((olleto1icAllIlb(alcat-wn Yent) prodllcedlesions on Sudan grass Johnson gll1SS aIH other smghums although natural infection a~ limited chiefly to sugarcane and Leptochloa jilifolmi8 (Lam) lkflu C lineolct Conln now considered a synonym for C qllminishy(olwl has been reported extegtl1sielr on Soghwn spp especially in the South rhe report by Jones and Teimel (13) of a fungus morshy

bull

bull

bull

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

31 ANlRRAC~OSE OF CEHEALS AXD GRASSES

bull phoJogictLlly simillu to O gral1vinicolltlllgt on alfalfa and their reference to correspvn(ellce indicating its presence on reel and white clover suggested It host range beyond the grasses lind the neell for testing legulIles in these investigations Examination of 5 host indices (9 1pound l(J 25 C) yielded 15 species in 4plusmn genem of the grass fnmily as hosts of this fungus Many were common pastme or weed grasses Control of ilnthmcllose of cereals and gmsses necessitates a knowledge of the relatin ability of the parasite to go from host to host

MATEHILS AND 11ETIIODS

TIlLeo methods of inoculation wen used Seed soil and foliage For seed inoculation ulI(lillnaged seeds of the crop being investigated el(~ imlllelsed in a hellvy spore suspension under paltial evacuation and while still moist wele planted in the greenhouse in sterilized soil heW at 28deg C Spores of the different isolates wem obtained ftom Duro cultures growll on potato-dextrose agat (rIle hosts and isolates used are given in table 2 Seedling blight Otmiddot -isib1e cortical damage to the lowCl illtell1o(ies and seminal roots was considered as positive infection Spring lye Clinton oats and Hem) wheat were inoculated in the same nUlIlIler and sown on ~lay D llH on the UniveLsity of Wisconsin Hill Farllls l1(al Madison

bull Strain relations were studie(l by soil inoculation with mycelial and

spore suspensions but the percentage of disease was appreciably lowel than with other methods and the results wem not snfliciently clear to wurrnnt Il detailed account

Foliage inoculations wen~ made on Sudnn grass and rye seedlings when about 6 inches high Sf)ores from potato-dextrose-agar cultures were slISptIHled in watetmiddot an( sprayed 011 unwounded plant surfaces The plants were then placed in moist chambers at 17deg to 20deg O for 48 hours Upon removal from the moist ehamoer the Sudan seedlings were incubatNl at 28deg and rye at 16deg or 20 0 for 1or 2 weeks The l)resshyellce of definite n(crotic lesions on the lea es was considered as evi( ence of su((essfuL infectioll The presence 0pound (o71elotrichuf)t gr(ffninicolllln as the pathogen was dett-imined by reisolation of the flLllgus from disshyeased tissues or by setose nceluli and conidia upon the lesions

TAIlL~l 2-Relatllc pathogenicity oj straillS of Oolletotlichwn glamishynicolunt as detclmine(l by sae(l inoculation in the gleenlwtlse at 28deg O

A erngc degree of infection 01]shy

1noclIllllll froll1- Co III 1110 n I H(nrv Oder-

Sudan lInprial I spring bruckcr grass r) c whcat barley ____________________1__________

(ornmon Sudall gras I icvprn ~[Od(rute---ll------ J

bull Hy(__ Xonc ~~ere Sight Sight Barlc )lolle 1 Nonc )lone___ do QuaCkgrnlis light- Slight__ _ [pl]tucky bluegrass Xonl ~[oderutc_

Composite of ulL Severc lcere ___ _

32 lECH~ICAL BULLElIX 1005 U S DEPI OF bull GHICULlUHE

EXPERIMENTAL RESCLTS

SEED l~OCUL-TION

Ditrenmces in specialization of the fungus were found 011 the hosts used The composite of all isolates was used to inoculate rye IIIHI oudan gltlSS seeds Isolations made ftom the diseased Sudan andlye seedshyBllgS ltsultedin what appeared to lle PUlC cultUles of the Sudan strain from Hullatt and the rye tLtlill 0 t the fungus from rye In this inshystllllec each host WlIS pamsitized by the isolate fwm it and was etfecshylive in screenillr out this stmill

Sudan gl~nSS ~as pamsitized ollly by the isolatlholll Sudan gmss Rye ditleled in that it was dis(nsNI nlost seen~ly by the r~e isohlte but all otllels except the isolate rlOll1 bader prodll1cd SOIlH diseuse suggestillg that the host-parasite relationship in rye WitS less specific (tuble 2) Vheat and barl(gt seed lings glOWIl al tlw high telllpcmtUle llIso showed slight illfedioll- with th( isolate from Lye and wheat was also infected with the fungus fWIll qlllHkglass The isolate fwm barley Wils IlOt pathogenic SUeil nOll pathogenic stlains wet obtailHd from old (ulmH and Itat sheaths of se(lal hosts The gnater cllgree of host sp(ei fiej ty 008(1(( j II Sudan glas~ 1Il ight Illl ( belll in f1uenced by the more filOlable tllllpelature (lH C) fOL this host than for the cereals 11ldi(lltiollS in this expeliment that isolates from othel hosts might b( injulious to lye werc Hot substantiated ill the Held tests

Impelial rj( inoculated with the isolate from rye was the only ino(ulation lesulting in disease devclopment in the field Rye plants ino(ulatNI with the rye stmin were yellowed and wilted in the rosette stage The plants appeared to re(ol1 at the jointing stage but yield data dplllonsttltell an apple(iable Joss 20 peleent (table 3) No obshyselvnblc symptolllS Lesulted from inoculations with the other stmins of the fungus used Rllll the ltlIT weiuht of plants furnished further evidellce of the laek of illfCttion

TABLt)3-RIZatilc pathogenicity of 81mliS of (oUetotli(hUJIL glamishyni(olum a~ determin(li 011 8ced ino(ulation -in tile field 8pring of HJrt

inoculum fromshy

flllprriul rye (li)ltOIl outs lIrJIIY whcat

Ryc __ OabL_ _ Q1Juck~rnss _ ((([lOp ____ _

Host speci licity was foullltli 11 the soi l-i nocul ation experiments Rye was blight(cl by the isolat( fOm rye and by olle [1OIrt glllJlu~ rligantell~ Vahl Sudan gla~s se(dlings wen killed lOll pelc(nt in the two vtrieshyties uSNl and an pettpnt of the sorghulIl s(edlings Wtle killed by the fungus flOm Hudun gmss Seminal roots appeared to b( parlitnlarly susceptibl() in these eXperilllllIt

bull

bull

bull

llll IH lltlmiddot IIallIlL jlPt I 1111 atlblllu~I of IPI 1IId ll 111111 1IIl- allli Ihl Illthd ill 1tmiddotIIIIW t~ -111middot (lt1 Ily 1)1 F HhtH ill

bull lI-OIld (lUfltVHP JI kwdl iunlwd fol illO(IIitlioll 1llrpllI

bull ~~ r

Imiddot

i

A

a h

I tmiddot J 11 Hi nmiddot t l~n 1 p Ita P uf ~t)dall lmiddota I I) Iud IlnpPIjt I 1 (I (J I i~ it ir onithmiddotd lh (JlrfJlllluJu IIJIIlJltllitoUIII j idnttmiddot 1uIl1 f -I J

1Idd~t t frHh~ i Hh ill t Ie 111 ~tltlat ~a flmiddottllIl 1i11Vitlld I I ) Iud If fir ilj f~ f~J f II t

1I ItI III 1 11 (1 (Ii 111 p till 0111 j olalld froll1 alfnlll ill r-middotII Iltollh 1llIllI frUlI1 thl -lllll It ill ((IIuil ~lilalld

bull IwmiddotdIllI Itmiddotd 111 PI 11111 II[ Ia lilli [(111 11 ((IIlOIIL liIP ilL()(lIlaltd

Sl~jir llrl~j bullbull gtu~ht Ililjutt nl Fulap (101 and IH plp ltllPHlI or 111tlll I 1t ~Hl t-d ~I ilaquo ljt 1 ILJi rt~i(IPPtmiddotir

34 LECHXrCAL BCLLEllX I 005 Lmiddot S DEPr OF AGHICQLlUHE

with these isolntes) as well as with isolates of C glaminicolwn froll1 the gmsses The legumes wete diseased only in the soil inoculated with the isolate itolll alJalfnfrOIll Geotmiddotgia They Wete not affected by isolilb-s of () glaminirolllln hom genss hosts nor were the gmsses affeNed by thtse isolatlsftom the llgull1es in either foilage OL seedshyinoculation tests shy

~OLlAG~ INOCLLATIO~

Foliage i Ilo(ulatiolls ltlClllonst lated specitic sirai ns 0 ( the fUllgus mOlT readily than did 1(((1 and soil inoelllntions RlldlII grass leaY(s were illfl~eted by the isolates from SOIgklun spp The leaves of rye wel( i 11 (CetNl by tIl( isolate ft1lI Iye and by till Olllmiddot Itom Ellnws gilant(llv (tablemiddot1 and fig Hi)

TheIlions Plo(u(Nl OJ 1)(](gtanmiddots by the isolate flom E giganteus (middotnlalmiddotged Illpidly nnd elC elllototic and similar to those ptodueed on IY(I by til(gt isolatQ hom rye but typitul stlomatic maSS(~S and aeeevuli fai lCd to (](clop 011 tlw fonner as they dill ill the latter

Tnrl~ ~t-HtZ(tile l)(ltllOgenic-itl of stlaillR of OoZletotliclLllln rpamishyl1iltolllll and two simiai iwl((ipoundw Iom legumes a8 detclmine(b bl fuliage ill()Cllatioll~ on 8c((Zlillg~ (] inrh(8 tall glown in the greenshyII(JlR(

ANn~e de~r(( of illfectioll 011shy

lno(IIIUII1 frorn-COllllllereinl 1111 pCrilli Hudun ~rtISS oye

~or(hllll tIIiIUf (Leoti) lodNntc Xonc bullS vlIllar Ilr slleallcns __ do_ Do

Do SCcrc Dow

S hull1)(middotI~ fodCratc Do if(1r areale Xonc bullbull S((r(1 AyroJlyrol crisaum do XOIICbull t rrplIIS do tl slIdlltii cia Do A Ir(lcil 1(allllllL do Do lqroMtr~(ll)(l doA ((lpil(lfi~ L do f)(lcllli~ glomlma (~llldi()Il Wi1 do Do n ylolterua (arihfiCld Wis) _ do Do lllWttS yill(lIllcll~ bull clo RCopreE fila HII1 _ bullbull do Xnnc ltfilll((1 c(llior cia J OVill(L _do Do fllbra do Do PItIIUlII prolelSI _bull do POl lrallnsi~ (Boyd Wisl do no P prltewtis (II UllIhird Wi~l clo Du J [lr~tel8is (~(ldisol1 Wi) do Do P pr(ltetl~is( Poyncttc i_j _cln Jrc(i(ogo 8ail(I L ~ _LIo_ DoJreliolliS lIb(L D(gtsr do_ Do

1StrolUatlc lUI1SSCS IUIII nCtrvuH JlrlmiddotS~llt bull Nt) strolllatic lllnssCS or lIccrvul (1r(5(lIt

bull

bull

bull

35

bull

bull

bull

~THHAC~OS~ O~ C1~HEALS A~D GHASSES

DISCCSSION ~D SClEL-UY

Host spedficity wilsfound alllong isolates of ioUctotlickttm gmlll shyinicolllm Leat inoculations gllve It reliable rapid method of detershymining the host leaction to specific isolatts Vhen the cereals and grnsses w(Ie not weuktmed by ullta-olable enilonment the diseasll WIIS produced only by the isolates from the Sltme or closely related species The nmiddotlative lack of specificity of the isolates on rye espeshyemIly in the greenhouse inoculation expeliment conducted at 28deg c illustrated the influence of unfaomble N1i lonment tem PetilIII Ie in this instance in jnlreasing seedling susceptibility of the host plant The (lxteut to which damage of this type might be expected to OC(lIl

in Halllre has not beC1l itm~stigated Crop rotlttiOlls ill whith closely llmiddotlateltl species do llOt sllcceed one allothpl appalpntly Ille uflicient saflguIIld agidnl-it building up 0 glamilliclJlulII ullless cnvironmental conditions ilwillding joil flltilily an lxtL(lIllCly lInfltVOrahe IsoshylullS obtailHd flom tlw 8((111 hosis show(a a wide mnge in paUloshygtnbityulI(l(llilt1entieallomlitiolls III( ioat(s 110111 oats amllHtrley USN in tll(st N(PlIillHlIts lIt good (Xa III pic of low pathogenicity

CONCLeSl0~S

Tlrisstudy 01 til( (tnopllI(llt o nnthlaenoe of ePIpals t1nclglasses elllpha~ip(l thC illlpoItanel of (ndlonrnpnial (onditiolls as Wlll liS of stage of host deelopmpnt and seneSc(nce of tissues Since the pat1loshygen (olldotlirAu7IbJJwnillicolllln (elS) Tis is It wlnm-tpmpemture Olgall iSIll anthllI(l1oe of thl cooL-temperatulC grasses is generally OhSPlTld late in SlllllmCI at 01 llNll mntlllitv of nIl host On the othel hand it cOllllllonly attackl-i t1ullan gmss and otwlWtlllll-weallwl hosts in midsUlIllTlN lit thp height of theil Ylgetatie yigol Rypound growJl 110111 inolrlatld Sllt( was injuled (L little when grown at sustailled low tlll1]1pratlllls but waR etrely disens(ltluIHlel warlll soil (on(1i timls J n (ontlast the tern pe1a tUle Ielt[u i1(lI1en ts of Sudan wal-i lind its palaitp Pl( so si111ilial flHlt diseas( dlelopnwllt was l-ievel~ at nil fl1llp(Lalults studied An impoltant lowPling of diseal-ie Il(l Was ohtaillNl throllgh lhe f1lltaonism of the oil mi(lofloll to the IHllait( (en though t1w inocultiin in these experiments was in (ontaet wit It tills( (l(IHI olganisms fol only Rhorl peliod Soil 11lOil-ihlle (xprtpd its gl(lai(st illfluCl1el upon diseae (ItwClopnwnt indirectly through its infl(n(p upon the leC] 01 antagollim

Thp pathologi(ul hitology of anthraenoe flllfh(t (pJl1ontlHted Illn t thi d iea( (oul d not corrpet h be (onsidp rpd OI1P of gpnpseell(( Tht (~C(lmiddotb()rne fungus pelletratpd lt1il((tl into Ihe vital and phyishyologieally atti C tisl-iues of both rye and Sudan glass seedlinhrs Losses of yield l(lrll(ll flom till lleploplIl(nt of anlllltcnos( upon seNllings pwn though thp plan[ npPI1(nllr IP(o(INl afttl a soulld (olonal Ioof Sytenl had bptll (stalll bhpd Th~ dlgrt( () f phyiologieal l)(gt(ia Iiza t ion (] f Ih0 pa Iasitp found

was (ol1sidtIl(lslltli(oi(llt to Illak( (IOp Iotatiolls thai I)i(p(l sllt(sioll of clos(y Iphltld pllllts applHl to be of valll( ill (Ollt oJ

36 ~lE(HXICAL nlLLETIX 1005 1 S DEP1 OF GIUCULlUHE

L1TERATlRE CITED

(1) AUX01OIIlS C J bull 11)11 STnms IX XTlIII0818 mnlt~middot U(nllI XU ~Txm If SI~ltIES

mlVIIXo~nmiddotNS JXlIllllllXO ~nn GHOWI1 Ot COLItTOTIIICIll1~

GIm()SIlt)(1I01ll~S I~XZ IX llmiddottrtmiddotIt~ OhiO JOIlr Sci 41 4-IlO (2) IheKwlIII I Il

lllll HOOT XII lII~IX~middot~CImiddot[(JS IW 1l~Imiddot IlY S()II~middotlmiddotXllI IS XOlrrll UAKOI Ihylopatlwlogy 1 [1HJ]-1i(1

(3) lh)lmiddotz~r~nt K t nnltl VArlXf-H l~~ lIm W~LK~ HsmItsKIUIl tXII XIlEItt SlIIUHllXmX X flS DIlteU

lOIUTOTltllHt ~l (mIlX(()Ie~[ (lES J 1fSOX PhytOpulh ~1$(I11 ) lOOJ-110 illus

(-I) Boruy II L lHl Il~l SOli 1ltfllIlI~H XU $~EU mn1tI0IlNrIOX (tS~ OP SOIl~

SI(KX~SS IX In 1XIJ$ IOSSIIIII UIIOUS OP (oxruo cummiddot IIX(1 I~TIJOllS WITH Wlnr N Dak Alr EXI1t HIli 1Iul 107 )-IlipIIIUS

liiJ ]kmiddotII~It 111 WIS ~TX(j1 iU UIiUASf IX rxmiddotrs middot1 pp III liS C1IillItta lind SllIIln

(0) (ltYJI~ J~ HIIII EII(lEltlON C W 1Jmiddot1middot1 lIl~ flln(I SJIH UP COIlmOllIll1I1( ~middotI(nM Phrtopnthology

H ()(iil IIll1s (i) (1I1IIO-1~ 11

111middot1Il l1I~ ()(117Im~n IW InI~LXrIlOSIOltllmiddot~1 ~lIICI(l~1 I TilE S~f1I -XII (111 ~l E8 OF SIIlX lUISS IhytO)l1l thology 0 11-10 IIII1S

un (1I0WIIlIllt ~ ( lKIObullbull IlISElt O~ 7~~rtmiddots (AIlmlJ 1 (middotOI[tmiddotroltcHu~r GltI-ICOLU1[

((~S ) IIS JlIllin II TOll 1bullAgl irl Ii ~a-S-la illIIS (I) n[STbullbullr

llJl2 1ltASITH n-m IS llfiIOXlll-1 1 PIl l[mlisoll Is no) EutaIITox C Y

lULl Im ItEI) 11lln 8(111 (s~ 1I~I(lJtl O~ 11I00ltESS Ln Agr Ilxpt bull ~tll Bill 111 2 PJl ilIlls

tIl) __ -- 111111 AltlmiddotAII P UHmiddot1 1I0SlmiddotIltAS1n lt~I I0SS IS lt~ll itO Oi SLGlt eSt Phytoputhshy

ultJ~)middot aJ 827 A~~7 illllS 11~) Fllllllltc G W RluIn H lOIISOS II )T 1I11111bltllHOXI R

1)middotI 11081 middotu 1I1I0m IWIIE (0 rllt IJllHSImiddotS OIlSlmn1J ox GtcSS~S IX (EltTUS ~snlti SmiddotIIfS lItltlX(1 1ImiddotII U SHIII Plant IIHluH Ihlllt Di Hptlmiddot Hnppl 13 [S 1middot-1-1-1 LI1(J(middot~111

I 111 JtlS~s I ll nnll ~l ~lIm T L imiddotto TIWEt llIll(~(ISJS (W 1~middotItmiddot U Hnlll Plant lnilaS Plant

I lis Uptl middotI 10-11 [ 110(18((11 ((I) Kmlluu B

1111 IHSE_~ 1111111 ~aS(1 lua)O~1 (OU-1 IUOIJ((TlOX X 111ISOIS U S 111 IlIln(11II1us IIHnt Dis Hllil 2 0-3 r11middotO(middotl~s((I]

(1) Lvm (1111(1 K~Ill n W lIJmiddotI TIIIHlTl( SImiddotlISlgt(I~ (lIn OAIgtS (EUTAIX 1TIIO(llX~S

(IQ (I PII t hoI I) 1- snl-l()(i ill liS tIn J 11t~fiT()S n

HImiddotIt 1lI~~lm (W IOIL8t8 IX OKIIIl~I Fi BIll lllint Imitls lllIlIt I H HpIT 2S iO [110((s8((11

In) HIKFU A J bull IlI1t1 HIIUlt H H WlH IXTUOIlI(TIOX 1) UES~U(1l 0 11 XT IIlSI$I 111 (1(1 illlls St

LOlli )(0 [PIOt(-s(lill IlSI Hns~sI1U

111 nmiddotJ XTJ[It( OS~ IX AltI-XSS IX na~ e S nil 1111 II [ ImlIS (hInt I Ii Hptl 2 21S [110(((111

1 lIJ bull H)middotI 01 nlllLI IX UK8 111-1(middotmiddot1 r H BIll IHlllt II(]IIS Plant

IJis HplImiddot 1 middot11-1 [1Iw(gtsPII] bull t()l HJIS n 1

WI TIlF nlloltTn OF 11101 HOOTS to rlll WIlI~T II XI Sd AIImiddot J I i 111u

37 ANTHHACXOS8 OF CEHEALS AND GHSSES

bull (l) SXFOllU 0 R

lila) (OItErOl1t1(Ill1 llICA~IISleOIt~l (ets) IIS S lAICASIIt ew SIt~1 SII UOOT rlssns Ot nx SArl Sci AgI ]) JjG-ajo Illm

(22) SfLlCY A 1gt 1I11(~Lxxs ~l wot Inms [S IllStASt$ W (EII$ ill (llI$SS Ohio AgI EX(l Stu

Rul W Jlll lSj-210 lIlus (23) SniMOxIIS 1 M

IVlII ICOUI IItnIOIlltX1 IX mIrIOS ro ICOOT ICOTS OP etUtAIS Sei Agl 10 liii-li-iO

124) - Ullil SILS B JlOaa tlUTlnIC SIlIHES Ui llllITIOXS m WlnI UOOTS IS UtIATIOX ~ro

IIIStAStS OP Im UOOI iYSnll Htbullbullgl 11 4m-HS lilliS () SluOlm H

IIHU ICOOTUOTS il) UFSInlS OP GltXS XII GUASiltS IX Till NOItIlIgUN (lCtl IIbullbullIXS ill tsnui STNns U~ Bill Plllnt Indus (hInt Ilis Hpll 81111Jll 111 [101]-US Ilroccssed]

tO) VfIS 1lt lUa-I em(K [S ut1l$loX l S nUl Ptlnt I nehls lIUIII niH Hl1tl 2j

mmiddotmiddotlW)7)-lS 1 Si-imiddotmiddotWa (In) s llaS-lI1i (11)4-1) ) -U t-t-~n OS-iU l~t-lant ltSB-lHmiddot1 ~R 7-~ a2H-aH7 nmiddotjii middotlIn-I -1Us-tjl iOH-lI middotI-ii-lR )jO-iiRJ U24-(ial

t

OH(Hi(iS (HH) L1IOelSHi(lj (i) WI-TEIC G

ItmiddotI tIX ~alt1C tlRSIC~KlItITHllClCtCilm _S wlwmx (lI~1C8Ttl UlliHg~ uxu 1IHlm [(OIUIOTltlelItlt GICUt [S(OII1 let 1180i) PhyLOshy(lath Ztlill 11 [~i l-~Il IIllls

bull

bull Pur saltmiddot by tillt HuwrlllttlHlilnt of lOtII11IlIt t S Gonrllllltnt IlInllnl OUll

Wasliington i U e - lricl lti eNlts

34 LECHXrCAL BCLLEllX I 005 Lmiddot S DEPr OF AGHICQLlUHE

with these isolntes) as well as with isolates of C glaminicolwn froll1 the gmsses The legumes wete diseased only in the soil inoculated with the isolate itolll alJalfnfrOIll Geotmiddotgia They Wete not affected by isolilb-s of () glaminirolllln hom genss hosts nor were the gmsses affeNed by thtse isolatlsftom the llgull1es in either foilage OL seedshyinoculation tests shy

~OLlAG~ INOCLLATIO~

Foliage i Ilo(ulatiolls ltlClllonst lated specitic sirai ns 0 ( the fUllgus mOlT readily than did 1(((1 and soil inoelllntions RlldlII grass leaY(s were illfl~eted by the isolates from SOIgklun spp The leaves of rye wel( i 11 (CetNl by tIl( isolate ft1lI Iye and by till Olllmiddot Itom Ellnws gilant(llv (tablemiddot1 and fig Hi)

TheIlions Plo(u(Nl OJ 1)(](gtanmiddots by the isolate flom E giganteus (middotnlalmiddotged Illpidly nnd elC elllototic and similar to those ptodueed on IY(I by til(gt isolatQ hom rye but typitul stlomatic maSS(~S and aeeevuli fai lCd to (](clop 011 tlw fonner as they dill ill the latter

Tnrl~ ~t-HtZ(tile l)(ltllOgenic-itl of stlaillR of OoZletotliclLllln rpamishyl1iltolllll and two simiai iwl((ipoundw Iom legumes a8 detclmine(b bl fuliage ill()Cllatioll~ on 8c((Zlillg~ (] inrh(8 tall glown in the greenshyII(JlR(

ANn~e de~r(( of illfectioll 011shy

lno(IIIUII1 frorn-COllllllereinl 1111 pCrilli Hudun ~rtISS oye

~or(hllll tIIiIUf (Leoti) lodNntc Xonc bullS vlIllar Ilr slleallcns __ do_ Do

Do SCcrc Dow

S hull1)(middotI~ fodCratc Do if(1r areale Xonc bullbull S((r(1 AyroJlyrol crisaum do XOIICbull t rrplIIS do tl slIdlltii cia Do A Ir(lcil 1(allllllL do Do lqroMtr~(ll)(l doA ((lpil(lfi~ L do f)(lcllli~ glomlma (~llldi()Il Wi1 do Do n ylolterua (arihfiCld Wis) _ do Do lllWttS yill(lIllcll~ bull clo RCopreE fila HII1 _ bullbull do Xnnc ltfilll((1 c(llior cia J OVill(L _do Do fllbra do Do PItIIUlII prolelSI _bull do POl lrallnsi~ (Boyd Wisl do no P prltewtis (II UllIhird Wi~l clo Du J [lr~tel8is (~(ldisol1 Wi) do Do P pr(ltetl~is( Poyncttc i_j _cln Jrc(i(ogo 8ail(I L ~ _LIo_ DoJreliolliS lIb(L D(gtsr do_ Do

1StrolUatlc lUI1SSCS IUIII nCtrvuH JlrlmiddotS~llt bull Nt) strolllatic lllnssCS or lIccrvul (1r(5(lIt

bull

bull

bull

35

bull

bull

bull

~THHAC~OS~ O~ C1~HEALS A~D GHASSES

DISCCSSION ~D SClEL-UY

Host spedficity wilsfound alllong isolates of ioUctotlickttm gmlll shyinicolllm Leat inoculations gllve It reliable rapid method of detershymining the host leaction to specific isolatts Vhen the cereals and grnsses w(Ie not weuktmed by ullta-olable enilonment the diseasll WIIS produced only by the isolates from the Sltme or closely related species The nmiddotlative lack of specificity of the isolates on rye espeshyemIly in the greenhouse inoculation expeliment conducted at 28deg c illustrated the influence of unfaomble N1i lonment tem PetilIII Ie in this instance in jnlreasing seedling susceptibility of the host plant The (lxteut to which damage of this type might be expected to OC(lIl

in Halllre has not beC1l itm~stigated Crop rotlttiOlls ill whith closely llmiddotlateltl species do llOt sllcceed one allothpl appalpntly Ille uflicient saflguIIld agidnl-it building up 0 glamilliclJlulII ullless cnvironmental conditions ilwillding joil flltilily an lxtL(lIllCly lInfltVOrahe IsoshylullS obtailHd flom tlw 8((111 hosis show(a a wide mnge in paUloshygtnbityulI(l(llilt1entieallomlitiolls III( ioat(s 110111 oats amllHtrley USN in tll(st N(PlIillHlIts lIt good (Xa III pic of low pathogenicity

CONCLeSl0~S

Tlrisstudy 01 til( (tnopllI(llt o nnthlaenoe of ePIpals t1nclglasses elllpha~ip(l thC illlpoItanel of (ndlonrnpnial (onditiolls as Wlll liS of stage of host deelopmpnt and seneSc(nce of tissues Since the pat1loshygen (olldotlirAu7IbJJwnillicolllln (elS) Tis is It wlnm-tpmpemture Olgall iSIll anthllI(l1oe of thl cooL-temperatulC grasses is generally OhSPlTld late in SlllllmCI at 01 llNll mntlllitv of nIl host On the othel hand it cOllllllonly attackl-i t1ullan gmss and otwlWtlllll-weallwl hosts in midsUlIllTlN lit thp height of theil Ylgetatie yigol Rypound growJl 110111 inolrlatld Sllt( was injuled (L little when grown at sustailled low tlll1]1pratlllls but waR etrely disens(ltluIHlel warlll soil (on(1i timls J n (ontlast the tern pe1a tUle Ielt[u i1(lI1en ts of Sudan wal-i lind its palaitp Pl( so si111ilial flHlt diseas( dlelopnwllt was l-ievel~ at nil fl1llp(Lalults studied An impoltant lowPling of diseal-ie Il(l Was ohtaillNl throllgh lhe f1lltaonism of the oil mi(lofloll to the IHllait( (en though t1w inocultiin in these experiments was in (ontaet wit It tills( (l(IHI olganisms fol only Rhorl peliod Soil 11lOil-ihlle (xprtpd its gl(lai(st illfluCl1el upon diseae (ItwClopnwnt indirectly through its infl(n(p upon the leC] 01 antagollim

Thp pathologi(ul hitology of anthraenoe flllfh(t (pJl1ontlHted Illn t thi d iea( (oul d not corrpet h be (onsidp rpd OI1P of gpnpseell(( Tht (~C(lmiddotb()rne fungus pelletratpd lt1il((tl into Ihe vital and phyishyologieally atti C tisl-iues of both rye and Sudan glass seedlinhrs Losses of yield l(lrll(ll flom till lleploplIl(nt of anlllltcnos( upon seNllings pwn though thp plan[ npPI1(nllr IP(o(INl afttl a soulld (olonal Ioof Sytenl had bptll (stalll bhpd Th~ dlgrt( () f phyiologieal l)(gt(ia Iiza t ion (] f Ih0 pa Iasitp found

was (ol1sidtIl(lslltli(oi(llt to Illak( (IOp Iotatiolls thai I)i(p(l sllt(sioll of clos(y Iphltld pllllts applHl to be of valll( ill (Ollt oJ

36 ~lE(HXICAL nlLLETIX 1005 1 S DEP1 OF GIUCULlUHE

L1TERATlRE CITED

(1) AUX01OIIlS C J bull 11)11 STnms IX XTlIII0818 mnlt~middot U(nllI XU ~Txm If SI~ltIES

mlVIIXo~nmiddotNS JXlIllllllXO ~nn GHOWI1 Ot COLItTOTIIICIll1~

GIm()SIlt)(1I01ll~S I~XZ IX llmiddottrtmiddotIt~ OhiO JOIlr Sci 41 4-IlO (2) IheKwlIII I Il

lllll HOOT XII lII~IX~middot~CImiddot[(JS IW 1l~Imiddot IlY S()II~middotlmiddotXllI IS XOlrrll UAKOI Ihylopatlwlogy 1 [1HJ]-1i(1

(3) lh)lmiddotz~r~nt K t nnltl VArlXf-H l~~ lIm W~LK~ HsmItsKIUIl tXII XIlEItt SlIIUHllXmX X flS DIlteU

lOIUTOTltllHt ~l (mIlX(()Ie~[ (lES J 1fSOX PhytOpulh ~1$(I11 ) lOOJ-110 illus

(-I) Boruy II L lHl Il~l SOli 1ltfllIlI~H XU $~EU mn1tI0IlNrIOX (tS~ OP SOIl~

SI(KX~SS IX In 1XIJ$ IOSSIIIII UIIOUS OP (oxruo cummiddot IIX(1 I~TIJOllS WITH Wlnr N Dak Alr EXI1t HIli 1Iul 107 )-IlipIIIUS

liiJ ]kmiddotII~It 111 WIS ~TX(j1 iU UIiUASf IX rxmiddotrs middot1 pp III liS C1IillItta lind SllIIln

(0) (ltYJI~ J~ HIIII EII(lEltlON C W 1Jmiddot1middot1 lIl~ flln(I SJIH UP COIlmOllIll1I1( ~middotI(nM Phrtopnthology

H ()(iil IIll1s (i) (1I1IIO-1~ 11

111middot1Il l1I~ ()(117Im~n IW InI~LXrIlOSIOltllmiddot~1 ~lIICI(l~1 I TilE S~f1I -XII (111 ~l E8 OF SIIlX lUISS IhytO)l1l thology 0 11-10 IIII1S

un (1I0WIIlIllt ~ ( lKIObullbull IlISElt O~ 7~~rtmiddots (AIlmlJ 1 (middotOI[tmiddotroltcHu~r GltI-ICOLU1[

((~S ) IIS JlIllin II TOll 1bullAgl irl Ii ~a-S-la illIIS (I) n[STbullbullr

llJl2 1ltASITH n-m IS llfiIOXlll-1 1 PIl l[mlisoll Is no) EutaIITox C Y

lULl Im ItEI) 11lln 8(111 (s~ 1I~I(lJtl O~ 11I00ltESS Ln Agr Ilxpt bull ~tll Bill 111 2 PJl ilIlls

tIl) __ -- 111111 AltlmiddotAII P UHmiddot1 1I0SlmiddotIltAS1n lt~I I0SS IS lt~ll itO Oi SLGlt eSt Phytoputhshy

ultJ~)middot aJ 827 A~~7 illllS 11~) Fllllllltc G W RluIn H lOIISOS II )T 1I11111bltllHOXI R

1)middotI 11081 middotu 1I1I0m IWIIE (0 rllt IJllHSImiddotS OIlSlmn1J ox GtcSS~S IX (EltTUS ~snlti SmiddotIIfS lItltlX(1 1ImiddotII U SHIII Plant IIHluH Ihlllt Di Hptlmiddot Hnppl 13 [S 1middot-1-1-1 LI1(J(middot~111

I 111 JtlS~s I ll nnll ~l ~lIm T L imiddotto TIWEt llIll(~(ISJS (W 1~middotItmiddot U Hnlll Plant lnilaS Plant

I lis Uptl middotI 10-11 [ 110(18((11 ((I) Kmlluu B

1111 IHSE_~ 1111111 ~aS(1 lua)O~1 (OU-1 IUOIJ((TlOX X 111ISOIS U S 111 IlIln(11II1us IIHnt Dis Hllil 2 0-3 r11middotO(middotl~s((I]

(1) Lvm (1111(1 K~Ill n W lIJmiddotI TIIIHlTl( SImiddotlISlgt(I~ (lIn OAIgtS (EUTAIX 1TIIO(llX~S

(IQ (I PII t hoI I) 1- snl-l()(i ill liS tIn J 11t~fiT()S n

HImiddotIt 1lI~~lm (W IOIL8t8 IX OKIIIl~I Fi BIll lllint Imitls lllIlIt I H HpIT 2S iO [110((s8((11

In) HIKFU A J bull IlI1t1 HIIUlt H H WlH IXTUOIlI(TIOX 1) UES~U(1l 0 11 XT IIlSI$I 111 (1(1 illlls St

LOlli )(0 [PIOt(-s(lill IlSI Hns~sI1U

111 nmiddotJ XTJ[It( OS~ IX AltI-XSS IX na~ e S nil 1111 II [ ImlIS (hInt I Ii Hptl 2 21S [110(((111

1 lIJ bull H)middotI 01 nlllLI IX UK8 111-1(middotmiddot1 r H BIll IHlllt II(]IIS Plant

IJis HplImiddot 1 middot11-1 [1Iw(gtsPII] bull t()l HJIS n 1

WI TIlF nlloltTn OF 11101 HOOTS to rlll WIlI~T II XI Sd AIImiddot J I i 111u

37 ANTHHACXOS8 OF CEHEALS AND GHSSES

bull (l) SXFOllU 0 R

lila) (OItErOl1t1(Ill1 llICA~IISleOIt~l (ets) IIS S lAICASIIt ew SIt~1 SII UOOT rlssns Ot nx SArl Sci AgI ]) JjG-ajo Illm

(22) SfLlCY A 1gt 1I11(~Lxxs ~l wot Inms [S IllStASt$ W (EII$ ill (llI$SS Ohio AgI EX(l Stu

Rul W Jlll lSj-210 lIlus (23) SniMOxIIS 1 M

IVlII ICOUI IItnIOIlltX1 IX mIrIOS ro ICOOT ICOTS OP etUtAIS Sei Agl 10 liii-li-iO

124) - Ullil SILS B JlOaa tlUTlnIC SIlIHES Ui llllITIOXS m WlnI UOOTS IS UtIATIOX ~ro

IIIStAStS OP Im UOOI iYSnll Htbullbullgl 11 4m-HS lilliS () SluOlm H

IIHU ICOOTUOTS il) UFSInlS OP GltXS XII GUASiltS IX Till NOItIlIgUN (lCtl IIbullbullIXS ill tsnui STNns U~ Bill Plllnt Indus (hInt Ilis Hpll 81111Jll 111 [101]-US Ilroccssed]

tO) VfIS 1lt lUa-I em(K [S ut1l$loX l S nUl Ptlnt I nehls lIUIII niH Hl1tl 2j

mmiddotmiddotlW)7)-lS 1 Si-imiddotmiddotWa (In) s llaS-lI1i (11)4-1) ) -U t-t-~n OS-iU l~t-lant ltSB-lHmiddot1 ~R 7-~ a2H-aH7 nmiddotjii middotlIn-I -1Us-tjl iOH-lI middotI-ii-lR )jO-iiRJ U24-(ial

t

OH(Hi(iS (HH) L1IOelSHi(lj (i) WI-TEIC G

ItmiddotI tIX ~alt1C tlRSIC~KlItITHllClCtCilm _S wlwmx (lI~1C8Ttl UlliHg~ uxu 1IHlm [(OIUIOTltlelItlt GICUt [S(OII1 let 1180i) PhyLOshy(lath Ztlill 11 [~i l-~Il IIllls

bull

bull Pur saltmiddot by tillt HuwrlllttlHlilnt of lOtII11IlIt t S Gonrllllltnt IlInllnl OUll

Wasliington i U e - lricl lti eNlts

35

bull

bull

bull

~THHAC~OS~ O~ C1~HEALS A~D GHASSES

DISCCSSION ~D SClEL-UY

Host spedficity wilsfound alllong isolates of ioUctotlickttm gmlll shyinicolllm Leat inoculations gllve It reliable rapid method of detershymining the host leaction to specific isolatts Vhen the cereals and grnsses w(Ie not weuktmed by ullta-olable enilonment the diseasll WIIS produced only by the isolates from the Sltme or closely related species The nmiddotlative lack of specificity of the isolates on rye espeshyemIly in the greenhouse inoculation expeliment conducted at 28deg c illustrated the influence of unfaomble N1i lonment tem PetilIII Ie in this instance in jnlreasing seedling susceptibility of the host plant The (lxteut to which damage of this type might be expected to OC(lIl

in Halllre has not beC1l itm~stigated Crop rotlttiOlls ill whith closely llmiddotlateltl species do llOt sllcceed one allothpl appalpntly Ille uflicient saflguIIld agidnl-it building up 0 glamilliclJlulII ullless cnvironmental conditions ilwillding joil flltilily an lxtL(lIllCly lInfltVOrahe IsoshylullS obtailHd flom tlw 8((111 hosis show(a a wide mnge in paUloshygtnbityulI(l(llilt1entieallomlitiolls III( ioat(s 110111 oats amllHtrley USN in tll(st N(PlIillHlIts lIt good (Xa III pic of low pathogenicity

CONCLeSl0~S

Tlrisstudy 01 til( (tnopllI(llt o nnthlaenoe of ePIpals t1nclglasses elllpha~ip(l thC illlpoItanel of (ndlonrnpnial (onditiolls as Wlll liS of stage of host deelopmpnt and seneSc(nce of tissues Since the pat1loshygen (olldotlirAu7IbJJwnillicolllln (elS) Tis is It wlnm-tpmpemture Olgall iSIll anthllI(l1oe of thl cooL-temperatulC grasses is generally OhSPlTld late in SlllllmCI at 01 llNll mntlllitv of nIl host On the othel hand it cOllllllonly attackl-i t1ullan gmss and otwlWtlllll-weallwl hosts in midsUlIllTlN lit thp height of theil Ylgetatie yigol Rypound growJl 110111 inolrlatld Sllt( was injuled (L little when grown at sustailled low tlll1]1pratlllls but waR etrely disens(ltluIHlel warlll soil (on(1i timls J n (ontlast the tern pe1a tUle Ielt[u i1(lI1en ts of Sudan wal-i lind its palaitp Pl( so si111ilial flHlt diseas( dlelopnwllt was l-ievel~ at nil fl1llp(Lalults studied An impoltant lowPling of diseal-ie Il(l Was ohtaillNl throllgh lhe f1lltaonism of the oil mi(lofloll to the IHllait( (en though t1w inocultiin in these experiments was in (ontaet wit It tills( (l(IHI olganisms fol only Rhorl peliod Soil 11lOil-ihlle (xprtpd its gl(lai(st illfluCl1el upon diseae (ItwClopnwnt indirectly through its infl(n(p upon the leC] 01 antagollim

Thp pathologi(ul hitology of anthraenoe flllfh(t (pJl1ontlHted Illn t thi d iea( (oul d not corrpet h be (onsidp rpd OI1P of gpnpseell(( Tht (~C(lmiddotb()rne fungus pelletratpd lt1il((tl into Ihe vital and phyishyologieally atti C tisl-iues of both rye and Sudan glass seedlinhrs Losses of yield l(lrll(ll flom till lleploplIl(nt of anlllltcnos( upon seNllings pwn though thp plan[ npPI1(nllr IP(o(INl afttl a soulld (olonal Ioof Sytenl had bptll (stalll bhpd Th~ dlgrt( () f phyiologieal l)(gt(ia Iiza t ion (] f Ih0 pa Iasitp found

was (ol1sidtIl(lslltli(oi(llt to Illak( (IOp Iotatiolls thai I)i(p(l sllt(sioll of clos(y Iphltld pllllts applHl to be of valll( ill (Ollt oJ

36 ~lE(HXICAL nlLLETIX 1005 1 S DEP1 OF GIUCULlUHE

L1TERATlRE CITED

(1) AUX01OIIlS C J bull 11)11 STnms IX XTlIII0818 mnlt~middot U(nllI XU ~Txm If SI~ltIES

mlVIIXo~nmiddotNS JXlIllllllXO ~nn GHOWI1 Ot COLItTOTIIICIll1~

GIm()SIlt)(1I01ll~S I~XZ IX llmiddottrtmiddotIt~ OhiO JOIlr Sci 41 4-IlO (2) IheKwlIII I Il

lllll HOOT XII lII~IX~middot~CImiddot[(JS IW 1l~Imiddot IlY S()II~middotlmiddotXllI IS XOlrrll UAKOI Ihylopatlwlogy 1 [1HJ]-1i(1

(3) lh)lmiddotz~r~nt K t nnltl VArlXf-H l~~ lIm W~LK~ HsmItsKIUIl tXII XIlEItt SlIIUHllXmX X flS DIlteU

lOIUTOTltllHt ~l (mIlX(()Ie~[ (lES J 1fSOX PhytOpulh ~1$(I11 ) lOOJ-110 illus

(-I) Boruy II L lHl Il~l SOli 1ltfllIlI~H XU $~EU mn1tI0IlNrIOX (tS~ OP SOIl~

SI(KX~SS IX In 1XIJ$ IOSSIIIII UIIOUS OP (oxruo cummiddot IIX(1 I~TIJOllS WITH Wlnr N Dak Alr EXI1t HIli 1Iul 107 )-IlipIIIUS

liiJ ]kmiddotII~It 111 WIS ~TX(j1 iU UIiUASf IX rxmiddotrs middot1 pp III liS C1IillItta lind SllIIln

(0) (ltYJI~ J~ HIIII EII(lEltlON C W 1Jmiddot1middot1 lIl~ flln(I SJIH UP COIlmOllIll1I1( ~middotI(nM Phrtopnthology

H ()(iil IIll1s (i) (1I1IIO-1~ 11

111middot1Il l1I~ ()(117Im~n IW InI~LXrIlOSIOltllmiddot~1 ~lIICI(l~1 I TilE S~f1I -XII (111 ~l E8 OF SIIlX lUISS IhytO)l1l thology 0 11-10 IIII1S

un (1I0WIIlIllt ~ ( lKIObullbull IlISElt O~ 7~~rtmiddots (AIlmlJ 1 (middotOI[tmiddotroltcHu~r GltI-ICOLU1[

((~S ) IIS JlIllin II TOll 1bullAgl irl Ii ~a-S-la illIIS (I) n[STbullbullr

llJl2 1ltASITH n-m IS llfiIOXlll-1 1 PIl l[mlisoll Is no) EutaIITox C Y

lULl Im ItEI) 11lln 8(111 (s~ 1I~I(lJtl O~ 11I00ltESS Ln Agr Ilxpt bull ~tll Bill 111 2 PJl ilIlls

tIl) __ -- 111111 AltlmiddotAII P UHmiddot1 1I0SlmiddotIltAS1n lt~I I0SS IS lt~ll itO Oi SLGlt eSt Phytoputhshy

ultJ~)middot aJ 827 A~~7 illllS 11~) Fllllllltc G W RluIn H lOIISOS II )T 1I11111bltllHOXI R

1)middotI 11081 middotu 1I1I0m IWIIE (0 rllt IJllHSImiddotS OIlSlmn1J ox GtcSS~S IX (EltTUS ~snlti SmiddotIIfS lItltlX(1 1ImiddotII U SHIII Plant IIHluH Ihlllt Di Hptlmiddot Hnppl 13 [S 1middot-1-1-1 LI1(J(middot~111

I 111 JtlS~s I ll nnll ~l ~lIm T L imiddotto TIWEt llIll(~(ISJS (W 1~middotItmiddot U Hnlll Plant lnilaS Plant

I lis Uptl middotI 10-11 [ 110(18((11 ((I) Kmlluu B

1111 IHSE_~ 1111111 ~aS(1 lua)O~1 (OU-1 IUOIJ((TlOX X 111ISOIS U S 111 IlIln(11II1us IIHnt Dis Hllil 2 0-3 r11middotO(middotl~s((I]

(1) Lvm (1111(1 K~Ill n W lIJmiddotI TIIIHlTl( SImiddotlISlgt(I~ (lIn OAIgtS (EUTAIX 1TIIO(llX~S

(IQ (I PII t hoI I) 1- snl-l()(i ill liS tIn J 11t~fiT()S n

HImiddotIt 1lI~~lm (W IOIL8t8 IX OKIIIl~I Fi BIll lllint Imitls lllIlIt I H HpIT 2S iO [110((s8((11

In) HIKFU A J bull IlI1t1 HIIUlt H H WlH IXTUOIlI(TIOX 1) UES~U(1l 0 11 XT IIlSI$I 111 (1(1 illlls St

LOlli )(0 [PIOt(-s(lill IlSI Hns~sI1U

111 nmiddotJ XTJ[It( OS~ IX AltI-XSS IX na~ e S nil 1111 II [ ImlIS (hInt I Ii Hptl 2 21S [110(((111

1 lIJ bull H)middotI 01 nlllLI IX UK8 111-1(middotmiddot1 r H BIll IHlllt II(]IIS Plant

IJis HplImiddot 1 middot11-1 [1Iw(gtsPII] bull t()l HJIS n 1

WI TIlF nlloltTn OF 11101 HOOTS to rlll WIlI~T II XI Sd AIImiddot J I i 111u

37 ANTHHACXOS8 OF CEHEALS AND GHSSES

bull (l) SXFOllU 0 R

lila) (OItErOl1t1(Ill1 llICA~IISleOIt~l (ets) IIS S lAICASIIt ew SIt~1 SII UOOT rlssns Ot nx SArl Sci AgI ]) JjG-ajo Illm

(22) SfLlCY A 1gt 1I11(~Lxxs ~l wot Inms [S IllStASt$ W (EII$ ill (llI$SS Ohio AgI EX(l Stu

Rul W Jlll lSj-210 lIlus (23) SniMOxIIS 1 M

IVlII ICOUI IItnIOIlltX1 IX mIrIOS ro ICOOT ICOTS OP etUtAIS Sei Agl 10 liii-li-iO

124) - Ullil SILS B JlOaa tlUTlnIC SIlIHES Ui llllITIOXS m WlnI UOOTS IS UtIATIOX ~ro

IIIStAStS OP Im UOOI iYSnll Htbullbullgl 11 4m-HS lilliS () SluOlm H

IIHU ICOOTUOTS il) UFSInlS OP GltXS XII GUASiltS IX Till NOItIlIgUN (lCtl IIbullbullIXS ill tsnui STNns U~ Bill Plllnt Indus (hInt Ilis Hpll 81111Jll 111 [101]-US Ilroccssed]

tO) VfIS 1lt lUa-I em(K [S ut1l$loX l S nUl Ptlnt I nehls lIUIII niH Hl1tl 2j

mmiddotmiddotlW)7)-lS 1 Si-imiddotmiddotWa (In) s llaS-lI1i (11)4-1) ) -U t-t-~n OS-iU l~t-lant ltSB-lHmiddot1 ~R 7-~ a2H-aH7 nmiddotjii middotlIn-I -1Us-tjl iOH-lI middotI-ii-lR )jO-iiRJ U24-(ial

t

OH(Hi(iS (HH) L1IOelSHi(lj (i) WI-TEIC G

ItmiddotI tIX ~alt1C tlRSIC~KlItITHllClCtCilm _S wlwmx (lI~1C8Ttl UlliHg~ uxu 1IHlm [(OIUIOTltlelItlt GICUt [S(OII1 let 1180i) PhyLOshy(lath Ztlill 11 [~i l-~Il IIllls

bull

bull Pur saltmiddot by tillt HuwrlllttlHlilnt of lOtII11IlIt t S Gonrllllltnt IlInllnl OUll

Wasliington i U e - lricl lti eNlts

36 ~lE(HXICAL nlLLETIX 1005 1 S DEP1 OF GIUCULlUHE

L1TERATlRE CITED

(1) AUX01OIIlS C J bull 11)11 STnms IX XTlIII0818 mnlt~middot U(nllI XU ~Txm If SI~ltIES

mlVIIXo~nmiddotNS JXlIllllllXO ~nn GHOWI1 Ot COLItTOTIIICIll1~

GIm()SIlt)(1I01ll~S I~XZ IX llmiddottrtmiddotIt~ OhiO JOIlr Sci 41 4-IlO (2) IheKwlIII I Il

lllll HOOT XII lII~IX~middot~CImiddot[(JS IW 1l~Imiddot IlY S()II~middotlmiddotXllI IS XOlrrll UAKOI Ihylopatlwlogy 1 [1HJ]-1i(1

(3) lh)lmiddotz~r~nt K t nnltl VArlXf-H l~~ lIm W~LK~ HsmItsKIUIl tXII XIlEItt SlIIUHllXmX X flS DIlteU

lOIUTOTltllHt ~l (mIlX(()Ie~[ (lES J 1fSOX PhytOpulh ~1$(I11 ) lOOJ-110 illus

(-I) Boruy II L lHl Il~l SOli 1ltfllIlI~H XU $~EU mn1tI0IlNrIOX (tS~ OP SOIl~

SI(KX~SS IX In 1XIJ$ IOSSIIIII UIIOUS OP (oxruo cummiddot IIX(1 I~TIJOllS WITH Wlnr N Dak Alr EXI1t HIli 1Iul 107 )-IlipIIIUS

liiJ ]kmiddotII~It 111 WIS ~TX(j1 iU UIiUASf IX rxmiddotrs middot1 pp III liS C1IillItta lind SllIIln

(0) (ltYJI~ J~ HIIII EII(lEltlON C W 1Jmiddot1middot1 lIl~ flln(I SJIH UP COIlmOllIll1I1( ~middotI(nM Phrtopnthology

H ()(iil IIll1s (i) (1I1IIO-1~ 11

111middot1Il l1I~ ()(117Im~n IW InI~LXrIlOSIOltllmiddot~1 ~lIICI(l~1 I TilE S~f1I -XII (111 ~l E8 OF SIIlX lUISS IhytO)l1l thology 0 11-10 IIII1S

un (1I0WIIlIllt ~ ( lKIObullbull IlISElt O~ 7~~rtmiddots (AIlmlJ 1 (middotOI[tmiddotroltcHu~r GltI-ICOLU1[

((~S ) IIS JlIllin II TOll 1bullAgl irl Ii ~a-S-la illIIS (I) n[STbullbullr

llJl2 1ltASITH n-m IS llfiIOXlll-1 1 PIl l[mlisoll Is no) EutaIITox C Y

lULl Im ItEI) 11lln 8(111 (s~ 1I~I(lJtl O~ 11I00ltESS Ln Agr Ilxpt bull ~tll Bill 111 2 PJl ilIlls

tIl) __ -- 111111 AltlmiddotAII P UHmiddot1 1I0SlmiddotIltAS1n lt~I I0SS IS lt~ll itO Oi SLGlt eSt Phytoputhshy

ultJ~)middot aJ 827 A~~7 illllS 11~) Fllllllltc G W RluIn H lOIISOS II )T 1I11111bltllHOXI R

1)middotI 11081 middotu 1I1I0m IWIIE (0 rllt IJllHSImiddotS OIlSlmn1J ox GtcSS~S IX (EltTUS ~snlti SmiddotIIfS lItltlX(1 1ImiddotII U SHIII Plant IIHluH Ihlllt Di Hptlmiddot Hnppl 13 [S 1middot-1-1-1 LI1(J(middot~111

I 111 JtlS~s I ll nnll ~l ~lIm T L imiddotto TIWEt llIll(~(ISJS (W 1~middotItmiddot U Hnlll Plant lnilaS Plant

I lis Uptl middotI 10-11 [ 110(18((11 ((I) Kmlluu B

1111 IHSE_~ 1111111 ~aS(1 lua)O~1 (OU-1 IUOIJ((TlOX X 111ISOIS U S 111 IlIln(11II1us IIHnt Dis Hllil 2 0-3 r11middotO(middotl~s((I]

(1) Lvm (1111(1 K~Ill n W lIJmiddotI TIIIHlTl( SImiddotlISlgt(I~ (lIn OAIgtS (EUTAIX 1TIIO(llX~S

(IQ (I PII t hoI I) 1- snl-l()(i ill liS tIn J 11t~fiT()S n

HImiddotIt 1lI~~lm (W IOIL8t8 IX OKIIIl~I Fi BIll lllint Imitls lllIlIt I H HpIT 2S iO [110((s8((11

In) HIKFU A J bull IlI1t1 HIIUlt H H WlH IXTUOIlI(TIOX 1) UES~U(1l 0 11 XT IIlSI$I 111 (1(1 illlls St

LOlli )(0 [PIOt(-s(lill IlSI Hns~sI1U

111 nmiddotJ XTJ[It( OS~ IX AltI-XSS IX na~ e S nil 1111 II [ ImlIS (hInt I Ii Hptl 2 21S [110(((111

1 lIJ bull H)middotI 01 nlllLI IX UK8 111-1(middotmiddot1 r H BIll IHlllt II(]IIS Plant

IJis HplImiddot 1 middot11-1 [1Iw(gtsPII] bull t()l HJIS n 1

WI TIlF nlloltTn OF 11101 HOOTS to rlll WIlI~T II XI Sd AIImiddot J I i 111u

37 ANTHHACXOS8 OF CEHEALS AND GHSSES

bull (l) SXFOllU 0 R

lila) (OItErOl1t1(Ill1 llICA~IISleOIt~l (ets) IIS S lAICASIIt ew SIt~1 SII UOOT rlssns Ot nx SArl Sci AgI ]) JjG-ajo Illm

(22) SfLlCY A 1gt 1I11(~Lxxs ~l wot Inms [S IllStASt$ W (EII$ ill (llI$SS Ohio AgI EX(l Stu

Rul W Jlll lSj-210 lIlus (23) SniMOxIIS 1 M

IVlII ICOUI IItnIOIlltX1 IX mIrIOS ro ICOOT ICOTS OP etUtAIS Sei Agl 10 liii-li-iO

124) - Ullil SILS B JlOaa tlUTlnIC SIlIHES Ui llllITIOXS m WlnI UOOTS IS UtIATIOX ~ro

IIIStAStS OP Im UOOI iYSnll Htbullbullgl 11 4m-HS lilliS () SluOlm H

IIHU ICOOTUOTS il) UFSInlS OP GltXS XII GUASiltS IX Till NOItIlIgUN (lCtl IIbullbullIXS ill tsnui STNns U~ Bill Plllnt Indus (hInt Ilis Hpll 81111Jll 111 [101]-US Ilroccssed]

tO) VfIS 1lt lUa-I em(K [S ut1l$loX l S nUl Ptlnt I nehls lIUIII niH Hl1tl 2j

mmiddotmiddotlW)7)-lS 1 Si-imiddotmiddotWa (In) s llaS-lI1i (11)4-1) ) -U t-t-~n OS-iU l~t-lant ltSB-lHmiddot1 ~R 7-~ a2H-aH7 nmiddotjii middotlIn-I -1Us-tjl iOH-lI middotI-ii-lR )jO-iiRJ U24-(ial

t

OH(Hi(iS (HH) L1IOelSHi(lj (i) WI-TEIC G

ItmiddotI tIX ~alt1C tlRSIC~KlItITHllClCtCilm _S wlwmx (lI~1C8Ttl UlliHg~ uxu 1IHlm [(OIUIOTltlelItlt GICUt [S(OII1 let 1180i) PhyLOshy(lath Ztlill 11 [~i l-~Il IIllls

bull

bull Pur saltmiddot by tillt HuwrlllttlHlilnt of lOtII11IlIt t S Gonrllllltnt IlInllnl OUll

Wasliington i U e - lricl lti eNlts

37 ANTHHACXOS8 OF CEHEALS AND GHSSES

bull (l) SXFOllU 0 R

lila) (OItErOl1t1(Ill1 llICA~IISleOIt~l (ets) IIS S lAICASIIt ew SIt~1 SII UOOT rlssns Ot nx SArl Sci AgI ]) JjG-ajo Illm

(22) SfLlCY A 1gt 1I11(~Lxxs ~l wot Inms [S IllStASt$ W (EII$ ill (llI$SS Ohio AgI EX(l Stu

Rul W Jlll lSj-210 lIlus (23) SniMOxIIS 1 M

IVlII ICOUI IItnIOIlltX1 IX mIrIOS ro ICOOT ICOTS OP etUtAIS Sei Agl 10 liii-li-iO

124) - Ullil SILS B JlOaa tlUTlnIC SIlIHES Ui llllITIOXS m WlnI UOOTS IS UtIATIOX ~ro

IIIStAStS OP Im UOOI iYSnll Htbullbullgl 11 4m-HS lilliS () SluOlm H

IIHU ICOOTUOTS il) UFSInlS OP GltXS XII GUASiltS IX Till NOItIlIgUN (lCtl IIbullbullIXS ill tsnui STNns U~ Bill Plllnt Indus (hInt Ilis Hpll 81111Jll 111 [101]-US Ilroccssed]

tO) VfIS 1lt lUa-I em(K [S ut1l$loX l S nUl Ptlnt I nehls lIUIII niH Hl1tl 2j

mmiddotmiddotlW)7)-lS 1 Si-imiddotmiddotWa (In) s llaS-lI1i (11)4-1) ) -U t-t-~n OS-iU l~t-lant ltSB-lHmiddot1 ~R 7-~ a2H-aH7 nmiddotjii middotlIn-I -1Us-tjl iOH-lI middotI-ii-lR )jO-iiRJ U24-(ial

t

OH(Hi(iS (HH) L1IOelSHi(lj (i) WI-TEIC G

ItmiddotI tIX ~alt1C tlRSIC~KlItITHllClCtCilm _S wlwmx (lI~1C8Ttl UlliHg~ uxu 1IHlm [(OIUIOTltlelItlt GICUt [S(OII1 let 1180i) PhyLOshy(lath Ztlill 11 [~i l-~Il IIllls

bull

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