Research on the Biocontrol ofM onocham us a lte rna tus Larvaeby B eauve ria bassiana with Severa l Synerg ists Survey, Indentification and Virulence Test of Pathogens of the P ine Sawyer Beetle,Monochamus alternatus, at Forest Farm ofMaanshan, Anhui Province Study on Excellent Strains ofBeauveria bassiana againstNotodontidae inPopulus × euramer icana and Controlling by D ifferent Formulations in Forest