多杀霉素与茚虫威混配对草地贪夜蛾的增效作用

Synergistic effect of spinosad and indoxacarb mixture on Spodoptera frugiperda(J.E.Smith)

草地贪夜蛾是一种为害玉米、高粱和小麦等多种作物的世界性重要害虫。于2019年1月从云南入侵我国并迅速扩散到大多数省份。当前我国防控草地贪夜蛾的主要手段是喷施化学杀虫剂。为筛选具有增效作用的杀虫剂混剂,延缓草地贪夜蛾抗药性发展,本文研究了多杀霉素与茚虫威两种不同作用机制的杀虫剂混配对草地贪夜蛾的增效作用。采用饲料混毒法测得多杀霉素与茚虫威对草地贪夜蛾的LD 50分别为5.41μg/g和17.74μg/g。多杀霉素和茚虫威两种药剂按不同质量比混配对草地贪夜蛾3龄幼虫均表现为相加或者增效作用,其中质量比为1∶9时增效作用最显著,共毒系数为147.3。

Spodoptera frugiperda(J.E.Smith)is one of the most important globally distributed agricultural pests which attack a wide range of crops including maize,sorghum and wheat.Since S.frugiperda invaded Yunnan province in January 2019,it has spread rapidly to most of provinces in China.Currently,spraying chemical insecticides is an important way to control S.frugiperda in China.To screen out the synergistic insecticide mixtures and delay the development of resistance,the joint action of insecticides spinosad and indoxacarb with different modes of action on insects was investigated in this paper.The LD 50 values of spinosad and indoxacarb on S.frugiperda were 5.41μg/g and 17.74μg/g,respectively.The results showed that the mixtures of spinosad and indoxacarb with different ratios have addition or synergistic effect on S.frugiperda larvae,among which the mixtures at ratio of 1∶9 showed significant synergistic effect and the co-toxicity coefficient was 147.3.