The cyst nematodes are a major group of plant pathogens of economic importance in many countries throughout the world. Considerable yield losses have been attributed to cyst nematodes attacking potatoes, sugar beet, soybean and cereals. Because of the protective cyst that is formed, which encloses the eggs, they pose special problems in their control and also in preventing their distribution in soil from infested areas. There has been much research on many aspects of the biology of cyst nematodes and the large number of publications are testimony to their importance as crop pests and of the...