牛心朴子与苦豆子两种提取物复配对小菜蛾幼虫的联合毒力作用

Investigate on the Common-toxicity of Cynanchum komarovii-Sophora alopecuroides Mixtures against Diamondback Moth

以牛心朴子和苦豆子为供试植物,小菜蛾幼虫为供试试虫,采用浸渍法测定了两种植物提取物复配后对小菜蛾幼虫的联合毒力。结果表明:牛心朴子与苦豆子提取物复配后具有增效作用,其中以干粉质量比为2∶1时增效作用最显著,其共毒系数(CTC)为248.30。复配物对小菜蛾幼虫具有显著的触杀活性,质量浓度为20.00 mg/mL时,72 h校正死亡率可以达到100%,致死中浓度LC50=2.0747 mg/mL。

The synergisms of mixtures in plant extracts Cynanchum komarovii and Sophora alopecuroides against Plutella xylostella was discussed by dipping method in the paper.the The result showed that the mixtures of Cynanchum komarovii and Sophora alopecuroides had observably synergisms,of which in mix-proportion of 2∶ 1 had the most significant with the common-toxicity coefficient（CTC） of 248.30.Meanwhile,the mixture had significant activity against Plutella xylostella,when treated with concentration of 20.00 mg/mL,the corrected mortality of contacting action was to be aboute 100% at 72 h,the lethal concentration of 50% was 2.0747 mg/mL.