Evaluation of Bt cotton hybrids for bollworm tolerance.

摘要

Twenty-eight cotton hybrids grown in India during 2005 were evaluated for resistance to Helicoverpa armigera, Earias vittella and Pectinophora gossypiella. Hybrids 4256, 4233, 4234, 4247 and Proagro 144 recorded very low infestation rates (0.0-0.62%) and yields that were up to 17.62 g per plant. Hybrids 4220, 4225, 4258, MECH 6301 and MECH 184 showed high infestation rates during the first picking, but during the second and third picking, infestation was almost nil. All the hybrids in the F2 generation exhibited greater infestation than those in the F1 generation.