印楝素与鱼藤酮及其复配混剂对斜纹夜蛾的毒效研究*

 用印楝素和鱼藤酮及其复配混剂对斜纹夜蛾3龄幼虫进行毒力测定。结果表明,印楝素和鱼藤酮单剂的毒力作用为一种剂量依赖关系;其复配混剂的触杀最佳配比为2∶6,此时印楝素和鱼藤酮浓度分别为200μg/mL和100μg/mL,共毒系数为423.15;其复配混剂的拒食最佳配比为3∶5,此时AFC₅₀为1.2mg/L,发育抑制率达90%以上只需35mg/L。

Study on Toxicity of Azadirathtin and Rotenoid and Their Admixture Against Spodoptera Iitura F.

The toxicity of azadirachtin and rotenone and their admixture against the 3rd-instar larvae of Spodoptera litura F.were conducted in laboratory.The results showed that azadirachtin and rotenone enhanced their toxicity with increase of the dosage.For the admixture,the optimum proportion for contact toxicity was 2∶6 when azadirachitin and rotenone concentration was 200μg/mL and 100μg/mL respectively.On this condition the co-toxicity coefficient was up to 423.15.The admixture produced a maximum anti-feeding effect and the AFC₅₀ was 1.2mg/L when the admixture was blended with azadirachitin and rotenone at the ratio of 3∶5.The admixture at 35mg/L could inhibit the larvae growth by more than 90%.