Toxicity of 2 Kinds of Hydro-azadirachtin A Against Insects

22,23-dihydroazadirachtin A and 2′,3′,22,23-tetrahydroazadirachtin A were hydrogenated derivates of azadirachtin A.AFC50 indexes of 2′,3′,22,23-tetrahydroazadirachtin A,and 22,23-dihydroazadirachtin A and zadirachtin A against 3rd instar larvae Spodoptera litura were 6.55 μg/mL,2.89 μg/mL and 0.87 μg/mL after 24 h treatment,and they were 12.61 μg/mL,8.01 μg/mL and 1.81 μg/mL after 48 h treatment.Antifeedant rates of 2′,3′,22,23-tetrahydroazadirachtin A,22,23-dihydroazadirachtin A and zadirachtin A at the concentration of 3 μg/mL against 3rd instar larvae of Plutella xylostella were 63.74%,80.77% and 85.33%.At the concentration of 5 μg/mL,Antifeedant rates of them against 3rd instar larvae of Heliothis armigera were 82.75%,90.74% and 94.90%.Revised mortalities of 2′,3′,22,23-tetrahydroazadirachtin A,22,23-dihydroazadirachtin A and zadirachtin A at the concentration of 3 μg/mL against 3rd instar larvae of P.xylostella were 67.90%,85.96% and 90.42%.At the concentration of 5 μg/mL,Revised mortalities of them against 3rd instar larvae of H.armigera were 94.19%,72.86% and 99.05%.22,23-dihydroazadirachtin A and 2′,3′,22,23-tetrahydroazadirachtin A could reduce body weight of H.armigera larvae obviously.