Effect of Neem Seed Kernel Extract (NSKE) on Helicoverpa armigera

Neem seed kernel extract (NSKE) reduced the oviposition of Helicoverpa armigera Hübnen in a dose dependent manner during the exposure periods of 0–24 h aad 24–48 8 and showed oviposition deterrency effect. The percentage reduction in oviposition due to NSKE treatment over control was maximum (60.9,59.0%) in higher doses of NSKE (10.0, 7.5%). The hatchability of the laid eggs was also affected on NSKE-treated surface. Ovicidal effect of NSKE was also noticed in different age groups of eggs and mortality decreased with increase in age group of eggs, the LC₅₀ being 31.54, 10.67, 5.78 and 2.18, respectively against the 48–72, 24–48, 12–24 and 0–12 h old eggs.