Plant parasitic nematodes are a main pest to crops. For ex am pie, the root-knot nematodes belonging to the genus Meloidogyne are worldwide in their distribution and attack almost every type of crop, causing considerable losses of yield and affecting quality of produce. The cyst nematodes within the genera Globodera and Heterodera constitute a major group of plant pathogens in many countries throughout the world, suppressing yields of potato, sugar beet, soybean and cereals. Several nematodes such as longidorids and trichodorids are implicated in the transmission of numerous plant viruses....

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...

Although nematodes had long been suspected as vectors of soil- borne plant diseases, unequivocal proof of their implication was not forthcoming until 1958 when Professor William Hewitt and his colleagues in California demonstrated experimentally that Xiphinema was the vector of grapevine fanleaf virus. This opened up a new and exciting field in plant pathology and discoveries quickly followed of other nematode species associated with soil-borne diseases of many different crops and in several countries. After the initial enthusiasm of discovering new vectors and new viruses there followed a...