杀虫剂对草地贪夜蛾幼虫的室内防效测定

Laboratory Control Efficacies of Insecticides against the larvae of Spodoptera frugiperda

草地贪夜蛾已经对多种杀虫剂产生了严重抗性,为筛选应急防控特效药剂,采用浸叶法研究了国家农业农村部推荐用于草地贪食蛾应急防控药剂清单中的7种不同作用机理杀虫剂对草地贪夜蛾甘肃种群3龄幼虫的室内防效。结果表明,60 g/L乙基多杀菌素悬浮剂2000倍液、5000倍液和2%甲维盐乳剂2000倍液、4000倍液处理对草地贪夜蛾3龄幼虫杀虫活性最好,药后24、48 h的校正防效均为100%。其次为0.5%苦参碱水剂300倍液、10%啶虫脒乳油1000倍液和200 g/L氯虫苯甲酰胺悬浮剂2000倍液处理,48 h的校正防效分别为82.86%、88.73%、88.57%。生物源农药8000 IU/uL苏云金杆菌悬浮剂100倍液处理速效性稍差,72 h后校正防效仅为43.28%;4.5%高效氯氰菊酯乳油1000倍液、1500倍液处理48 h的校正防效均不足30%,表明草地贪夜蛾可能对该药产生严重的抗性。

Spodoptera frugiperda has developed serious resistance to a variety of insecticides.In order to screen the special insecticides for emergency control,we studied the laboratory control efficacies of 7 different insecticides recommended by the Ministry of Agriculture and Rural Affairs on the third instar larvae of S.frugiperda by using the leaf dipping method.The results showed that treatments of 60 g/L ethyl polygermicide SC 2000 times and 5000 times,and 2% ME 2000 times,4000 times showed strong toxic effects on the third instar larvae of S.frugiperda.The correction and control efficiency of 24 h and 48 h after treatment were all 100%.The calibration and control effects of 0.5% matrine AS 300 times,10% acetamidine EC 1000 times and 200 g/L chlorobenzamide SC 2000 times for 48 h were 82.86%,88.73% and 88.57%,respectively,which also showed strong insecticidal activities.The corrected control effects of 8000 IU/uL biogenic pesticide was only 43.28% after 72 h treatment with 100 times of Bacillus thuringiensis SC.The corrected control effect of 4.5% beta-cypermethrin EC 1000 times and 1500 times treatments for 48 h were less than 30%,indicating that S.frugiperda may develop serious resistance to this insecticide.