Abstract:In order to confirm the potential application of four isolates of entomogenous fungi for biocontrol of Plutella xylostella, the insecticidal activities of the four isolates to P.xylostella was determined by bioassay method. The taxonomic identification of the isolates was also carried out with multiphase taxonomy. The virulent bioassay against P.xylostella showed that the best isolate was GZU-BCECWC113, with the lowest value of LT50 and LC50. The LT50 was 3.33 days when the concentration of conidia was 1.6×108 conidia/mL,and the value of LC50 was 0.45×105 conidia/mL when the tested insects were infested 8 days. The corrected mortality rate of GZU-BCECWC113 was 89.47%, which was the highest one among the four isolates. By using the traditional taxonomic methods and phylogenetic analysis based on ITS1-5.8S-ITS2 rRNA sequences, the four isolates were identified. The results showed that GZU-BCECWC113, GZU-BCECWQ16, GZU-BCECW122 and GZU-BCECWKKS2 belonging to Paecilomyces catenianulatus, P.fumosorosenus, P.cicadae and P.tenuipes, respectively.