商暾 刘英 杨茂发 于晓飞 陈亦钗

摘 要：为了解虫螨腈与茚虫威混配对草地贪夜蛾幼虫的增效作用，本研究采用浸叶法测定了两种药剂对草地贪夜蛾3龄幼虫的毒力以及混配后的增效作用。结果表明：茚虫威处理24 h后的致死中浓度（LC50）值大于虫螨腈，分别为10.135、4.047 mg/L;而处理48 h后茚虫威的LC50值反而小于虫螨腈，分别为3.027、3.406 mg/L;虫螨腈与茚虫威混配后，虫螨腈：茚虫威为1∶5、2∶5、1∶10、1∶15时在处理24 h和48 h后均表现为增效作用，2∶25配比则表现为相加作用。因此，可采用虫螨腈与茚虫威混配来提高田间草地贪夜蛾防控的效果。

关键词：草地贪夜蛾;虫螨腈;茚虫威;增效作用;相加作用

中图分类号：S433.4

文献标识码：A

文章编号：1008-0457（2021）03-0069-05

国际DOI编码：10.15958/j.cnki.sdnyswxb.2021.03.011

Toxicity of Chlorfenapyr，Indoxacarb and Their Mixtures Against Spodoptera frugiperda

SHANG Tun1，LIU Ying1，YANG Maofa1，2*，YU Xiaofei2，CHEN Yichai1

（1.Institute of Entomology，Guizhou Provincial Key Laboratory for Agricultural Pest Management of the Mountainous Region，Guizhou University，Guiyang，Guizhou 550025，China; 2.College of Tobacco Science，Guizhou University，Guiyang，Guizhou 550025，China）

Abstract：

To understand the synergistic effect of the mixtures of chlorfenapyr and indoxacarb against the larvae of Spodoptera frugiperda.In this study，the toxicity and synergistic effect of two insecticides and their mixtureson third instar larvae of S.frugiperda were determined by leaf immersion method.The results showed that the lethal concentration （LC50） valueof indoxacarb treated S.frugiperda for 24 h was greater than that of chlorfenapyr，whichwere10.135 and 4.047mg/L respectively.while that was the oppositeafter 48 h treatment，the LC50 of indoxacarb was 3.027 mg/L，chlorfenapyr was 3.406 mg/L.After mixture with chlorfenapyr and indoxacarb，the ratio of the two were 1∶5，2∶5，1∶10 and 1∶15showed synergistic effects after 24 h and 48 h treatment.However，the ratio of 2∶25 showed additive effect.Therefore，the mixtures of chlorfenapyr and indoxacarb could be used to improve the effect of prevention and control of S.frugiperda in the field.

Keywords：

Spodoptera frugiperda;chlorfenapyr;indoxacarb;synergistic effects;additive effect

草地贪夜蛾Spodoptera frugiperda是鳞翅目Lepidoptera夜蛾科Noctuidae灰翅夜蛾属Spodoptera的具有迁飞能力强、繁殖速度快、危害程度重等特点的一种多食性害虫[1，2]。 2019年1月入侵我国以来，草地贪夜蛾凭借其极强的迁飞能力，累计危害玉米面积达108万hm2，已成为我国玉米上重大突发性、暴食性害虫，严重危害我国粮食安全[3-4]。

为防止草地贪夜蛾的快速繁殖危害，保护粮食安全，我国在各发生地区使用化学方法进行应急防控[1]。目前报道的对草地贪夜蛾有较好防效的杀虫剂有：甲氨基阿维菌素苯甲酸盐、乙基多杀菌素、除虫脲、虱螨脲、茚虫威、氯虫苯甲酰胺、氟苯虫酰胺、虫螨腈等[5-6]。但是，长期单一或重复使用杀虫剂会使草地贪夜蛾对杀虫剂产生抗性或交互抗性[7]，且草地贪夜蛾的迁飞习性会将具有遗传特征的抗药性在不同发生地进行扩散[8]，导致杀虫剂的防治效果降低[2]。……