Abstract:

A total of 12 strains of Metarhizium anisopliae Sorokin were tested for pathogenicity to Hylobitelus xiaoi，and a superior strain was used to infect trials in a forest. The results indicated that the strain Ma1291-2 had strong pathogenicity to H.xiaoi after treatment for 30 d by dipping inoculation with (1.5±0.5)×10⁸ conidia·mL^-1. The correct mortality, the muscardine cadaver rate and the conidia content individual of H.xiaoi were respectively 70.59%, 70.81% and （1.90±0.34）×10⁸dia individual, and the quickest median lethal times (LT₅₀) were 13.89 d. The median lethal concentration (LC₅₀) was 1.135 3×10⁶ conidia·mL^-1. By infecting trials to H.xiaoi in a forest with the strain Ma1291-2, mortality of the treatment was extremely significant higher than the control, the correct mortality, the muscardine cadaver rate and the conidia content individual of H.xiaoi were 57.85%±1.19%, 55.43%±2.90% and (1.12±0.41)×10.8 conidia individual after 30 d, respectively, and the median lethal times (LT₅₀) was 16.56 d. The results suggest that the strain of Ma1291-2 has great application value.

Key words: Hylobitelus xiaoi, Metarhizium anisopliae, pathogenicity, strain screening