Residual Toxicity of Neem-Based Insecticides against Egg Parasitoid Trichogrammatoidea bactrae Nagaraja

A study was carried out with neem-based insecticides, viz., azadirachtin (0.03%EC, 0.15%EC, 0.3%EC, 1%EC), neem seed oil (1, 2 and 3%), neem seed extract 5% and dashparni ark (ten plant leaf extract) 4%, on Trichogrammatoidea bactrae Nagaraja (Hymenoptera: Trichogrammatidae) adults using the thin film residue method under laboratory conditions. After coating glass vials with neem-based insecticides, the adults of T. bactrae were released on the first, fifth, and tenth days of coating and the mortality was assessed. Among all neem-based insecticides, azadirachtin 1%EC was observed to be harmful to adults of T. bactrae on the first, fifth and tenth days. In contrast, neem seed extract 5% and dashparni ark 4% were found safe.