The dissemination of nematodes pathogens in irrigation water has been recognised as a serious threat to crop production (Faulkner and Bolander, 1966; 1970 a and b; Tobar-Jimenez and Palacios-Mejia, 1976). Nothing is known about the numbers and distribution of nematodes in irrigation water in India. This paper reports the results of a survey on the occurrence of nematodes in irrigation water of the Upper Ganges Canal, a major irrigation canal for the Gangetic planes of North India.
