(Heterodera rostochiensis), a roundworm of the family Heteroderidae. Body length, about 1 mm.

The golden nematode is a parasite of the roots (less often, of the tubers) of potatoes, tomatoes, and, occasionally, deadly nightshade. It is found in Europe, Asia, North and South America, Africa, and Australia. It is also found in several republics of the USSR. Development from the larval stage to maturity takes place in the tissues of the roots or tuber of the host plant. The transparent wormlike male crawls out of the root into the soil; the anterior end of the female remains attached to the root or tuber, its swollen body covered by a thick cuticle, protruding outside the plant. The male dies after fertilization. The female forms more than 1,000 eggs; these remain inside her body, which turns into a cyst after her death. In the spring the larvae emerge from the cyst and embed themselves in the plant roots.

The golden nematode retards the development of the host plant, significantly reducing yield; when infestation is extreme the potato plants form either no tubers at all or from one to three tiny tubers. A kilogram of soil in heavily infested fields may contain as many as 2, 500 cysts of golden nematode. Counter-measures include quarantine, planting resistant varieties of potatoes, crop rotation and removal of the infested roots and tubers from the fields, and disinfection of the soil with chloropi-crin, Carbathion, or Nemagon.