龟纹瓢虫和六斑月瓢虫对农药的敏感性研究

The Sensitivity of Propylaea japonica and Menochilus sexmaculata(Coleoptera:Coccinellidae)to Differential Insecticides

瓢虫是重要的害虫生防资源,喷施农药对其构成了严重威胁。本文旨在探讨华南3地2种常见优势瓢虫(龟纹瓢虫和六斑月瓢虫)对常用杀虫剂的敏感性。采用玻璃管药膜法测定了广州、南宁和海口龟纹瓢虫和六斑月瓢虫对5种农药的敏感性。从对药剂的敏感性来看,龟纹瓢虫和六斑月瓢虫均对毒死蜱最为敏感,LC_(50)分别在42.47~249.19 mg/L之间和57.04~224.16 mg/L之间,其次是高效氯氰菊酯和高效氯氟氰菊酯,LC_(50)分别在162.49~496.89 mg/L之间和203.17~404.21 mg/L之间,对阿维菌素和甲氨基阿维菌素苯甲酸盐相对不敏感,LC_(50)分别在227.27~2334.51 mg/L之间和339.44~2454.93 mg/L之间;从对不同地理种群敏感性来看,龟纹瓢虫和六斑月瓢虫南宁种群和广州种群对药剂不敏感,而海口种群相对敏感。本研究结果可为反映当地用药水平和田间保护天敌瓢虫提供理论依据和用药指导。

Ladybeetle is an important resource for insect pest biological control.However,it is now feeling threatened by various insecticides.This study aimed to obtain the sensitivity of Propylaea japonica and Menochilus sexmaculata(Coleoptera:Coccinellidae)in South China to five differential frequently-used insecticides.Bioassays were conducted with adults of P.japonica and M.sexmaculata by using a standard glass tube residual film method.The results showed that the toxicity(LC_(50))of P.japonica and M.sexmaculata were most sensitive to chlorpyrifos,the LC_(50)s were 42.47~249.19 mg/L and 57.04~224.16 mg/L,respectively,followed by pyrethroids,the LC_(50)s were between 162.49 to 496.89 mg/L for beta-cypermethrin and 203.17 to 404.21 mg/L for lambda-cyhalothrin on two ladybeetle species,then by abamectin and emamectin benzoate,the LC_(50)s were among 227.27~2334.51 mg/L and 339.44~2454.93 mg/L,respectively.The results also revealed that the sensitive of ladybeetles among different geographical strains were significantly different to tested insecticides.Haikou strain was more sensitive to Nanning and Guangzhou strains.The results could be used as a reflection of the current level of use of insecticides in different regions and field protection of natural enemies ladybirds to provide theoretical basis and pesticide guidance.