斑蝥素微乳剂优化配方(25号)毒力测定

采用菜蛾(Plutella xylostellaL.)三龄幼虫为试虫对自行研制的生物源农药杀虫剂斑蝥素微乳剂优化配方(25号)的杀虫活性进行了室内毒力测定。结果表明:试虫中毒后主要表现为活动能力下降至逐渐死亡,且虫体前中部发黑。该优化配方对试虫的胃毒致死中浓度LC50,触杀致死中浓度LC’50,选择性拒食中浓度AFC50,非选择性拒食中浓度NAFC50分别为0.80±0.02,0.85±0.05,1.80±0.12和1.26±0.04 mg.L-1;与阿维菌素丙酮溶液(CK1)相比,该配方对试虫的触杀作用高出57.5%,选择性拒食作用高出59.5%;综合评估指数(EI)高出38.5%;与斑蝥素丙酮溶液(CK2)相比,该配方对试虫的胃毒作用、触杀作用、选择性拒食作用、非选择性拒食作用、综合评估指数(EI)分别提高44.4%,62.6%,61.9%,86.6%和73.6%,差异均达显著水平(P≤0.05)。

Bioassay of Optimized Cantharidin (No.25) Micro-emulsion

Bioassay of the 3rd instar larvae of Plutella xylostella L were used to determine the toxicity of No.25 optimized Cantharidin Micro-emulsion(ME).The results showed that the main symptoms were the descending activity of the tested insects and the forepart of the body becoming black.The stomach poison active LC_(50),the touch poison active LC'_(50),the selective AFC_(50) and the nonselective_(N)AFC_(50) were 0.80±0.02,0.85±0.05,1.80±0.12 and 1.26±0.04 mg·L~(-1),respectively.Compared with abamectin(CK_(1)),the touch poison action was 57.5% higher,the selective antifeedant action was 59.5% higher and the evaluating indexes(EI) of optimized Cantharidin ME were 38.5% higher,respectively.Compared with Cantharidin(CK_(2)),the stomach poison action,the touch poison action,the nonselective antifeedant action and the evaluating indexes(EI) of optimized Cantharidin ME increased 44.4%,62.6%,61.9%,86.6%,and 73.6%,respectively.They were all at a significant level(P≤0.05).