Virulence Study on Mixture of Common Pesticides with Beauveria bassiana against Spodoptera exigua(Hübner)

[Objective] The research aimed to study the virulence of the mixture of common pesticides with Beauveria bassiana against Spodoptera exigua(Hubner).[Method] Six kinds of insecticides and three kinds of fungicides were chose to determine the effects on mycelial growth of B.bassiana.In terms of the result,four kinds of insecticides with more compatibility were picked out,which were Jiaweiyan,Chujin,Tieshazhang and Kangfu.Then,the four insecticides at 1/5 and 1/10 conventional field use concentrations were mixed with the suspension of B.bassiana at concentration of 1×107 spores/ml respectively,to study the effects of the mixture against S.exigua(Hubner).[Result] The mixture containing insecticides at low concentration were less effective than that at high concentration.Two days after treatment,the controlling effects of the mixture containing Jiaweiyan and Chujin increased to 53.0%-70.0%.Ten days after treatment,the controlling effects were up to over 92.0%.And the controlling effects of the two kinds of mixture containing Jiaweiyan both came to 97.7%.[Conclusion] The study can provide the scientific basis for preparing the high effective and lower toxic biological preparation.