HPIPM:Eggplant, Pepper and Tomato Nematodes

Author: Howard F. Schwartz and David H. Gent

Taxonomy

Domain	Eukarya
Kingdom	Animalia

Scientific Name

Nematoda

Scientific Name Synonyms

Nemata

Nematodae

Common Name

nematodes, roundworms, threadworms

Identification and Life Cycle

Several species of nematodes can cause economic damage to tomato, eggplant, and pepper in the High Plains production region, including root-knot, sting, and stubby-root nematodes. The life cycles of different nematode species vary, and may include feeding on the outside of roots or penetration and development within roots. Some nematodes vector viruses (i.e., tomato black ring virus, tomato ringspot virus, and tobacco ringspot virus) or predispose plants to other diseases (i.e., Verticillium wilt). Nematodes survive between solanaceous crops by feeding on other crops and weeds, and are spread in contaminated soil on machinery, wind blown soil, and irrigation water.

Plant Response and Damage

Nematode injury varies among species, but can include galls on roots (root-knot), necrosis of roots (root-lesion), a “rat-tail” appearance (sting nematode), or a subtle stubby-appearance (stubby-root). Aboveground plant symptoms may range from no apparent injury to less vigorous growth to stunting, yellowing, wilting, and death. Nematodes reduce tomato yield by an estimated 15% in the southeastern US, but accurate estimates of crop loss are not available in the High Plains.

Biological Control

Incorporation of green manure crops such as sudangrass, sesame, rapeseed, white mustard, or perennial ryegrass the season before solanaceous crops are planted can reduce some nematode populations.

Cultural Control

Crop rotation may provide suppression or control of some nematode species, but most nematodes that attack solanaceous crops have host ranges that include many crops and weeds. Therefore, effective weed control is essential for reducing nematode populations. Adequate but not excessive irrigation and fertilization will help plants tolerate some nematode feeding. Flooding fields can reduce nematode populations.

Chemical Control

Nematicides and soil fumigation effectively suppress many nematode species, but are most effective when combined with cultural practices that reduce nematode populations. Nematode injury often only occurs in localized areas in fields, and these areas can be effectively managed by spot-treatment with nematicides.

Due to constantly changing labels, laws and regulations, the sponsors of this web site assume no liability for the suggested use of any chemicals noted in the management section. Contact your local pest management personnel for current information on labeled pesticides that can be used for the intended plant disease, insect pest or weed.