Comparative Study on Bioassay Methods for Beauveria bassiana Virulence Against the Asian Corn Borer,Ostrinia furnacalis(Guenée)

The pathogenicity of B.bassiana against 3rd instar larvae of O.fumacalis were assessed with dose-response assays by feeding method and dipping method respectively,the standardization of Beauveria bassiana to the Asian corn borer,Ostrinia fumacalis(Guenee) was built.The result showed that,no significant difference was observed among corrected mortality,LT50 and LC50 of the 3rd instar larvae by feeding method and dipping method under the different spore concentrations of 105,106,107 and 108 CFU/mL among the treatment groups.But the mortality of the larvae by feeding method was lower than that of dipping method in the control groups of 3rd instar larvae,respectively.So,feeding method was a more reliable method for bioassay of B.bassiana against O.fumacalis than dipping methods,and that was simple and without actions of repeated insects transfer,thus more reliable experimental results could be obtained.