Morphological parameters of tomato genotypes and resistance to fruit borer helicoverpa armigera (Hubner)

The tomato fruit borer Helicoverpa armigera (Hubner) causes heavy loss in tomato due to tenderness of the plant. Identifying resistant/ tolerant genotypes is required for deploying host plant resistance as an IPM strategy. This study evaluates the morphological characters of 22 genotypes for resistance to H. armigera, under field conditions at the Vegetable Research Farm, Banaras Hindu University during rabi 2017-18 and 2018-19. The morphological characters viz., no. of branches/ plant and calyx/ fruit revealed a positive correlation while density of trichomes on leaves and calyx and fruit pericarp thickness showed negative correlation, when correlated with fruit weight loss. In contrast, the trichome density on calyx/ leaves exhibited an inverse relation with no. of eggs laid. The genotypes which showed 0.1-10% fruit weight loss could be considered as resistant.