Effects of Sowing Dates on Variability of Perineal-Pattern of Meloidogyne Incognita

In the present investigation effect of sowing dates was study on the morphometric of perineal pattern. Seedlings of tomato cv. Marglobe were inoculated with single egg mass population of Meloidogyne incognita in the first week of every month from January to December. It was found that various morphometric characters of the female studied were high when plants were inoculated during September and October; intermediate in March, April, July and August and low in the remaining months with no development of mature females in December and January. This variation may be due to temperature prevailing in these months. Out of several characters studied, dorsal and ventral arch, lines of right and left side of the pattern were highly variable. However, vulval width, vulval and distance and B/A rato remain unaffected.