Division of Nematology, Indian Agricultural Research Institute, New Delhi-110012, India
*Part of thesis submitted by senior author for award of M. Sc. degree of P.G. School, I.A.R.I., New Delhi-110012.
Interaction studies amongst Heterodera zeae, Meloidogyne incognita and Tylenchorhynchus vulgaris, carried out at two levels of inoculum, namely, 500 and 1000 nematodes per 500 cc. of soil indicated that the combined effect of H. zeae & M. incognita or H. zeae &. T. vulgaris or M. tncognita and T. vulgaris at both levels of inoculum on plant growth was similar to that of their individual effects. In combined inoculations of three nematode species while the inoculum levels of H. zeae and T. vulgaris tended to interact differently in different combinations with respect to plant growth. M. incognita tended to supress it progressively with increasing inoculum. Lower levels of T. vulgaris at 500 larvae of H. zeae and lower levels of M. incognita at 1000 level had synergistic effect on cyst production. Gail formation by M. incognita was adversely affected by presence of one or both of the other nematode species. Final population of M. incognita was adversely affected by both inoculum levels of H. zeae but not with those of T. vulgaris. Final population of T. vulgaris was found to be leduced by low levels of H. zeae and both levels of M. incognita.
