Isolation, Identification, Biological Characterization, and Pathogenicity of Entomopathogenic Fungus from the Larvae of the (Scopoli) (Lepidoptera: Pyralidae).

At Qinghai agriculture districts, poses a significant threat to spring rapeseed cultivation through its larvae burring into the rapeseed kernels and feeding seeds. To protect the ecological environment of the Qinghai-Tibet Plateau, it is essential to research and develop biological control technologies for pest management. In this study, we isolated and purified a new entomopathogenic fungus from the carcasses of larvae, which was identified as based on morphological characteristics combined with ITS rDNA and 18S rDNA sequence analyses. Subsequently, the optimal growth conditions for the strain were determined as follows: SDAY medium, fructose as the carbon source, peptone as the nitrogen source, 25 °C, pH 6.0-7.0, and a 0:24 (light:dark) photoperiod.However, UV can significantly reduce fungal spore production. The bioassay result shows its pathogenicity was a concentration-dependent effect on , and younger larvae were more susceptible. With 1 × 10 spores/mL inoculated, survival of second instar larvae decreased by the greenhouse pot experiment. In conclusion, exhibits a significant biocontrol potential against .