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Root Lesion Nematode:Biology and Management

Bikash BhandariGraduate student

Department of plant, Environment and

Soil Sciences

02/16/2011

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Introduction

Lesion nematode means they produce

conspicuous necrotic lesions on host roots.

Belongs to the genus Pratylenchus

Ranked third only to Rootknot and Cyst

nematodes in terms of economic impact oncrops (Sasser and Freckman, 1987)

keys.lucidcentral.org

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Introduction

Most important species:P. penetrans(400 hosts)

P. vulnus(fruit trees

and ornamentals)

P. brachyrus(peanut,

soybean)

P. zea(corn)

P. coffee(coffee)

www.fao.org

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Taxonomy

Phylum Nematoda

Class - Secernentea

Order - Tylenchida

Superfamily - TylenchoideaFamily - Pratylenchidae

Genus -

Pratylenchus

plpnemweb.ucdavis.edu

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Distribution

World wide distribution:Asia - 40

Europe - 32

Africa - 16North America - 27

South America - 22

Ocean - 12

Antartica -1

Source: Castillo and Vovlas, 2007

bizbox.slate.com

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Distribution

Source: Castillo and Vovlas, 2007

70 species arereported.

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Biology

Migratory endoparasites

Feeding restricted entirely to root cortex (notroot stele)

Most problem in

perennial crops

apsnet.org

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About 0.3-

0.9mm long

Invisible tonaked eye

Set off lipregion

Low and flat infront

3 annules

Stylet is

prominent andhave a largebasal knob.

http://nematode.unl.edu/prapen.htm

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Biology

Oesophagus overlappedthe intestine.

2 dark spicules

Bursa

http://nematode.unl.edu/prapen.htm

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Life cycle

Sexual

Asexual

(Parthenogenesis)

Six life stages

(4-8 weeks)

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Life cycle

http://www.apsnet.org/edcenter/intropp/lessons/Nematodes/

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Symptoms

Healthy vs. lesion nematode-infected roots

systems. (Courtesy C. S. Huang)

Small yellowish dark brown lesions(glycosides)

Root girding and disintegration

hrt.msu.edu

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Symptoms

Patches of stunted and chlorotic plants

Soil test is necessary

Potato early dying disease in field. (Courtesy R.C. Rowe)

Corn field showing nematode injury to roots

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Dissemination

Irrigation and surface drainage

Transport of

infected plants/soils

uprooted.jessicareeder.comcountryliving.com

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Nematode management

Pre-plant Fumigation

Nematicides

Seed treatment

Crop rotation

Resistant varieties

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