Barley mixtures emphasizing Barley mixtures emphasizing pest aspectspest aspectspest aspectspest aspects

Velemir NinkovicVelemir NinkovicDepartment of Ecology SLUDepartment of Ecology SLUDepartment of Ecology, SLU, Department of Ecology, SLU, 

Uppsala, SwedenUppsala, Sweden

OutlineOutline

• Introduction

• Plant responses to allelobiosis

• Effects of allelobiosis on aphids

• Responses of aphid natural enemies to allelobiosis• Responses of aphid natural enemies to allelobiosis

• Summary of results

War Co-existenceWar Co existence

Picture by Philip Patenall from Trends in Plant Science 2005. Vol. 10 No. 3

Allelobiosis: Chemical interactions between undamaged plants whichChemical interactions between undamaged plants which have subsequent effects on other organisms.

Ninkovic et al. (2006) in Communication in Plants, pp. 421-434

Pettersson et al. (2003) BCPC Crop Science and Technology, 2, 1135-1144

Volatile profiles of two barley cultivars  

5

6

Alva

Kara

4

)

3

mount in

 sam

ple (ng

2

mean am

1

0

How do we do it?

Exposing system with two chamber cagesExposing system with two chamber cages

How does the receiving plant react?

Change of biomass allocationChange of biomass allocation

0.7 Kara exposed to AlvaKara exposed to Kara

0.5

0.6

g m

g-1 )

Kara exposed to KaraUnexposed Kara

0.4

actio

n (m

g

0.2

0.3

omas

s fra

0.1

Roo

t bi

ANOVA F2,86= 14.9, P< 0.0001

00 50 100 150 200 250 300 350 400 450

Total biomass (mg)

Ninkovic (2003) J. Experim. Bot. 54: 1931

Unexposed Kara Exposed Kara

Leaf temperature measured by IR camera

Kara exposed to Alva unexposed Kara

Decreased leaf temperature in exposed plants

0 0

Dag 0 Dag 1 Dag 2 Dag 3Day 0 Day 1 Day 2 Day 3

-0,2

0,0r (

C°)

ture

C°

-0,6

-0,4

mpe

ratu

r

n.s.

tem

pera

t

-0,8

,

i bla

dtem

n.s.

e in

leaf

t

-1,2

-1,0

Ski

llnad

D

iffer

ence

-1,4

S

P=0.017 P=0.013

D

n.s. = Not significant

Ninkovic (2010) in Plant Communications from Ecologic Perspective 75-86

Can changes in the plant affect aphids and how?how?

Bird cherry-oat aphid Rhopalosiphum padi

Allelobiosis reduced aphid settling on cultivar Kara after

K d t When exposed to volatiles from

Kara exposed toFrida

Kara exposed toAlva *

When exposed to volatiles from other cultivars

K d t

Kara exposed toHulda

Frida

0 0,2 0,4 0,6 0,8 1

Kara exposed toKara

Proportion aphids settlingp p g

Kara mixed withAlva *

When grown in mixture with other cultivars

Kara mixed with

Kara mixed withFrida *

other cultivars

Only Kara plants

Kara mixed withHulda

Ninkovic et al. 2002 Ent. Exp. Appl. 102: 177

0 0,2 0,4 0,6 0,8 1Proportion aphids settling

P<0,05*

Screening for allelobiotic activity of different barle c lti arsdifferent barley cultivars

30(%

)

25

c activity

 

15

20

llelobiotic

10

ency of a

0

5

Freq

u

0

Old cultivars Modern cultivars

Year of cultivar release onto the market and allelobiotic effect on aphid acceptanceallelobiotic effect on aphid acceptance

1.0

1.1

1.0

1.1

0.8

0.9

At/A

0

0.8

0.9

At/A

0

0 6

0.7 P=0.019r2 = 0.148

0 6

0.7 P=0.046r2 = 0.109

1880 1900 1920 1940 1960 1980 2000

Year of release of receiver cultivar

0.61880 1900 1920 1940 1960 1980 2000

Year of release of emitter cultivar

0.6

of receiver cultivar of emitter cultivar

Kellner et al (2010) Theoretical and Applied Genetics 121:1133

Probing

E – phloemphase

Non probing Probingbetween cells E1 E2

Non-probingphase (np)

epidermis mesofphyll phloem

bladlus

labium

stylet

Changed aphid feeding behaviour in exposed barley cultivar

25

s ExposedP=0.04

barley cultivar

20

g ph

ases

Unexposed

15

feed

ing

P=0.01P=0.01

10

er a

phid

n.s.

P=0.02

5

Num

be

n.s.

0

n.s. = non significant

Reduced aphid growth rate on plants exposed to another barley cultivar

0.25) P=0.025

another barley cultivar

0.20g-1 d

ag-1

)

0.15

rate

(µg

µ

0.10

e gr

owth

r

0.05d re

lativ

e

0.00Exposed plants Unexposed plants

Aph

i

Exposed plants Unexposed plants

Ninkovic et al. in prep.

…allelobiosis affect aphidsi th fi ld?in the field?

Photo: Sate al Abassi

Aphid population development in cereals

Establishment Exponential growth Summer migrationSpring migration

May June JulyMay June July

Reduced aphid infestation on Prestige in cultivar mixture

3000Prestige grown with FriedaPrestige

2500

g

2000

w s

ampl

e

P=0.0051500

er 1

m ro

w

500

1000

Aph

ids

pe

0

500A

0

12 June 19 June 27 June 3 July 10 July

Ninkovic et al. in prep.

Photo: Annhild Andersson

….. confirms the reduction of aphid population developmant

in the plots in the cagesp g

70

80

90

ts 3500

4000

mpl

e

Prestige

Prestige P=0.007

40

50

60

70

ds p

er 2

0 pl

an

2000

2500

3000

0.5m

row

sam

gi Frieda

0

10

20

30

Aph

i

500

1000

1500

Aoh

ids

per 0

010 June 18 June 24 June 1 July 8 July 16 July 0

16 June 23 June 30 June 7 July 13 July 19 July

Ninkovic et al. in prep.

Can changes in the plant affect aphid nat ral enemies and ho ?natural enemies and how?

S t l d bi d

Photo: Sate al Abassi

Seven-spot ladybirdCoccinella septempunctata

Ladybird response to aphid‐induced plant volatiles 

4.5

5.0

3.5

4.0

3.5

4.0

arm

P=0.01 P=0.023.0

arm

2.5

3.0

fact

oret

er a

2.0

2.5

lfact

oret

er a

1.5

2.0

Vis

its in

olf

1.0

1.5

Vis

its in

ol

Photo: Sate al Abassi

0.5

1.0

0.5

1.0

0.0Infested plant without aphids

Unifested plant0.0

Infested plant with aphids

Unifested plant

Ninkovic et al (2001) Biological Control 21: 191

Increased attraction of ladybirds to odour from plants exposed to an other barley cultivarexposed to an other barley cultivar

66

P=0.011

4

5

m

P=0.009

4

5

rm

3

4

tore

ter a

rm

3

4

ctor

eter

a

2

ts in

olfa

c

2

sits

in o

lfa

Photo: Sate al Abassi

1Vis

i

0

1Vis

0

Hulda exposed to Alva

Unexposed Hulda

0

Alva + Hulda Hulda + Hulda

Ninkovic et al. (2011) Oecologia 166:391Glinwood et al. (2009) Arthropod-Plant Interactions 3:215

Effects of cultivar mixture on population development of C septempunctata in the field trialdevelopment of C. septempunctata in the field trial  

25

HuldaAlvaH ld Al*

20

bird

s

Hulda-AlvaAphid population

*

15

er o

f lad

yb *

10

ean

num

be

0

5Me

P<0,05*

05 June 6 June 9 June 13 June 16 June 21 June 23 June 28 June 5 July 7 July

Ninkovic et al. (2011) Oecologia 166:391

Allelobiosis affects…..

Biomass allocation and l fleaf temperature

Aphid host acceptance, aphid growth and population developmentp

Ladybird olfactory response and occurrence in the field

AcknowledgmentsSLU Uppsala SLU UmeåStockholm University

Velemir Ninkovic

Robert Glinwood

Elham Ahmed

Torgny Näsholm

Ulrika Ganeteg

Lisbeth Jonsson

Gabrielle Delp

Barbara KarpinskaElham Ahmed

Martin Kellner

Sate al Abassi

Barbara Karpinska

Therese Gradin

Katarina Herbst

Annhild Andersson

Iris Dahlin

Sara Merhabi

Lisa Beste

Al k d L ik

SLU AlnarpInger Åhman

Erika Qvarfordt

Jan Pettersson

Pierre Henri Clergeot

Aleksandra Losvik

Mattias Persson

Pierre-Henri Clergeot

www.plantcommistra.com

Thank youThank youfor your for your

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