GLOBODERA ELLINGTONAE: A NEW POTATO CYST NEMATODE

SPECIES

INGA A. ZASADA AND WENDY PHILLIPSUSDA-ARS HORTICULTURAL CROPS RESEARCH LABORATORY,

CORVALLIS, OR

RUSSELL E. INGHAMOREGON STATE UNIVERSITY, CORVALLIS, OR

Outline

Globodera in the United States Discovery of Globodera

ellingtonae in the United States What we know about G.

ellingtonae Conclusions

Globodera in the United States

PCN are considered quarantine pests for the U.S. as they can cause severe economic damage to host crops if uncontrolled

1932 – G. rostochiensis found in New York; confined to this area as a result of regulatory and management practices

2006 - a sample comprised of tare dirt from a grading station in Blackfoot, ID was determined to contain G. pallida

2008 – three nematode samples distinct from known PCN species were found in Oregon and Idaho

2013 - 19 G. pallida-infested field have been identified in Idaho

Globodera spp.

Elevated to a subgenus in 1959 (Skarbilovich) and genus in 1975 (Behrens)

Recognized species: G. achilleae 1973 (yarrow) G. artemisiae 1972 (artemisia) G. chaubattia 1984 (apple) G. ellingtonae 2012 G. hypolysi 1983 G. leptonepia 1953 (solanaceous plants) G. mexicana 1967 (tomato, black nightshade) G. millefolii 1965 G. mirabilis 1971 G. pallida 1973 (potato, tomato, solanaceous

weed) G. psudorostochiensis 1963 G. rostochiensis 1923 (potato, tomato,

solanaceous weed) G. tabacum complex1954 -1972 (solanaceous

plants) G. zelandica 1984 (tree fuschia)

Globodera spp. lifecycle

Hatching factor

Syncytium formed“transfer cell”

Contains 400-500eggs

Males are need for reproduction in most species

Some images from mactode.com

Diapause

Narrow host range

“Ultimate in evolutionary specialization”

J1

Globodera ellingtonae discovery

2008 – three nematode samples distinct from known PCN species were found in Oregon and Idaho Oregon Department of Agriculture processed samples from

Powell Butte, OR, 6 cysts were found In Idaho cysts were found in 2 fields (Caribou and Teton

Counties, Idaho) for a total of 4 cysts All cysts sent to USDA-ARS Nematology Laboratory for

identification 2010 – USDA-ARS and Oregon State University

demonstrate that potato and tomato are hosts for this Globodera (Skantar et al., 2011) OSU voluntarily closes Powell Butte research facility

Map of OSU Powell Butte Farm

2012 – described as a new species by Handoo et al. Morphologically G.

ellingtonae differs from other Globodera by its distinctive J2 tail and by one or more differences in stylet length, cuticular ridges, spicules, etc…

Based upon ITS sequence data G. ellingtonae is distinct from G. pallida, G. rostochiensis, G. tabacum, and G. mexicana

Multiplex RT-PCR used for detection of G. rostochiensis, G. pallida, and G. tabucum resulted in no false positive detections involving G. ellingtonae

Globodera ellingtonae discovery

G. ellingtonae

Handoo et al. (2012)

Globodera ellingtonae discovery

What we know - hatching

Hatch of Globodera ellingtonae Over Time in Root Exudates

Day

0 5 10 15 20 25

% h

atc

h re

lativ

e t

o t

ota

l ha

tch

ove

r tim

e

0

20

40

60

80

100

Potato root exudate Tomato root exudate

*

Hatch of Globodera ellingtonae in Root Exudates

Wat

erP

otat

oTo

mat

oLa

mbs

quar

ter

Hai

ry V

etch

Pig

wee

dO

ats

Whe

atY

ello

w M

usta

rdC

anol

a

Juve

nile

ha

tch/

cyst

0

50

100

150

200

2502-week hatch in exudate After transfer to PRD

Roy Navarre (USDA-ARS) – Zasada et al. (2013)

What we know – potato hosts

Host Status of Potato Varieties to Globodera ellingtonae

Potato Variety

Des

iree

Bur

bank

Um

atilla

Mod

ocN

orla

ndY

ukon

Mar

is P

iper

Atla

ntic

Set

ina

Rep

rod

uct

ion

fac

tor

0

10

20

30

40

50

60

70

Trial 1 Trial 2

b

a

d

e e e

c

b

cB

A

BBC

CC

D D D

All Ro1resistant

P < 0.05

What we know – host range

Desiree

Eggplant

Tomatillo

Bell pepper

Jalapeno

0 5 10 15 20 25 30 35 40 45 50

Host status of other Solanaceous crops

Reproduction factor (Pf/Pi)

Tomato

Oats

Barley

Alfalfa

0 1 2 3 4 5 6 7 8

Host status of rotation crops grown at Powell Buttte

Trial 2

Trial 1

Reproduction factor (Pf/Pi)

What we know - biology

Population dynamics of G. ellingtonae life stages in soil on potato

What we know - pathogenicity

2012 - Inoculated potato ‘Russet Burbank’ with 0, 5, 10, 20, 40 eggs/g soil

2013 – Inoculated potato “Russet Burbank’ and ‘Desiree’ with 0, 5, 10, 20, 40, 80 eggs/g soil

Desiree Results

Pathogenicity – Desiree 2013

Effect of Globodera ellingtonae onPotato Aboveground Biomass at Harvest

Desiree

No significant differences

Effect of Globodera ellingtonaeon Total Tuber Weight

Desiree

No significant differences

Russet Burbank Results

Pathogenicity – Burbank 2012

Total Yield of Potato 'Russet Burbank' Inoculatedwith Different Initial Egg Densities of Globodera ellingtonae

Initial egg density (in 3000 g soil)

Uni

nfes

ted

5 eg

gs/g

10 e

ggs/

g

20 e

ggs/

g

40 e

ggs/

g

Tu

ber

yie

ld (

g/p

lan

t)

0

200

400

600

800

1000

1200

1400no difference; P > 0.05

Pathogenicity – Burbank 2013

Effect of Globodera ellingtonaeon Total Tuber Weight

Russet Burbank

AA

A

AB AB

B

Differences significant at P = 0.06

Effect of Globodera ellingtonae onPotato Aboveground Biomass at Harvest

Russet Burbank

No significant differences

Effect of G. pallida on yield of a moderately intolerant potato cultivar

Yie

ld (

mt/

ha)

Initial Population Density (eggs/g soil)

Trudgill and Phillips

Conclusions

1. Biological data supports the morphological and molecular conclusion that G. ellingtonae is a distinct species from G. pallida and G. rostochiensis

2. G. ellingtonae appears to be more closely related to G. rostochiensis

3. It is still not clear to what extent G. ellingtonae is a pathogen of potato – this nematode is not regulated!!

4. Future research will include: expanded host range, continued molecular characterization, and identification of ways to manage this new nematode species

Acknowledgements

Oregon State University

Nadine WadeSolomon Yilma

Dee Denver

FundingOregon Potato CommissionUSDA-APHISUSDA-ARS

Zasada USDA-ARS LabAmy Peetz

Duncan KroeseMariella Ballato

Amanda Howland

University of IdahoLouise-Marie Dandurand

Joe Kuhl

USDA-ARSRoy NavarreChuck Brown

Xiaohong WangRich NovyJonathan

Whitworth