Root-lesion nematode

Pratylenchus penetrans (Cobb) Filipjev & Schuurmans-Stekhoven

Distribution: Widespread; common to all fruit-growing regions in eastern North America.

Root-lesion nematodes (A) are microscopic, migratory endoparasites that feed on the root systems of many crops. Affected trees appear stunted, may exhibit chlorosis or yellowing of the leaves, and have poor yields; young trees may be killed. Newly infected roots typically show a reddish brown, elongated lesion in the vicinity of invasion. Severely infected root systems lack the fine-texture, fibrous roots or may have tufts of necrotic roots that resemble a witches' broom. Disease is common on light-textured soils.

Crops Affected: apples, cherries, peaches, pears, plums

Management

Avoid planting on sites with a history of root-lesion nematode or on light-textured soils have soils tested before planting.

Similar Species

Any disease or disorder affecting the root system or rootstock/scion union can produce similar above-ground symptoms. Positive diagnosis generally requires isolation of the nematodes.