Toxicity of to and effects on its natural predators.

Entomopathogenic fungi (EPF) are economical and environmentally friendly, forming an essential part of integrated pest management strategies. We screened six strains of (B1-B6) (Hypocreales: Cordycipitaceae), of which B4 was the most virulent to (Hendel) (Diptera: Tephritidae). We further assessed the biological characteristics of strain B4 and the environmental factors influencing its ability to infect . We also evaluated the effects of B4 on two of the natural predators of . We found that strain B4 was the most virulent to 3rd instar larvae, pupae, and adult , causing mortality rates of 52.67, 61.33, and 90.67%, respectively. B4 was not toxic to eggs. The optimum B4 effects on were achieved at a relative humidity of 91-100% and a temperature of 25°C. Among the six insecticides commonly used for control, 1.8% abamectin emulsifiable concentrate had the strongest inhibitory effect on B4 strain germination. B4 spraying affected both natural enemies ( and ), reducing the number of and killing adults. We found a valuable strain of EPF (B4) that is virulent against many life stages of and has great potential for the biological control of . We also provide an important theoretical and practical base for developing a potential fungicide to control .