| Beauveria bassiana (Balsamo) Vuillemin is a classical entomopathogenic fungus in microbial control of insect pests. It has been attractive for its wide use and superior production property, and has been developed into a variety of commercial formulations of mycoinsecticides in the world. In order to further improve current mass production technology, a set of new technics of semisolid fermentation was developed, which used the plastic board and plastic reseau board as carriers to produce B. bassiana. At the same time, the effect of Monochamus alternatus control with B. bassiana by the different measures and the influence upon the community in the forest were studied and the application of Beauveria brongniartii and Metarhizium anisopliae were tried against Anoplophora glabripennis in order to look for new microbial control agentsLiquid seed culture of B. bassiana was studied at different temperatures. The results showed that biomass was the highest with the 20% peeled potato and 2% white sugar, natural pH, temperature at 25℃, and 36 hours for cultivation. For semisolid fermentation, silkworm powder was chosen as the nitrogen source at natural pH, and an adhesive matter was added into the semisolid medium to make the medium attach fast to the carriers. 4.47×108 conidia per cm2 were yielded by immersing inoculation method. The semisolid medium was composed simple with proper stickiness, suitable for B. bassiana to grow on.Technics of semisolid culture was studied, the results showed that inoculation amount 10%, thickness 0.25cm on the carrier, culture temperature at 25℃ and environmental RH 95% were optimal for the fungus to sporulate. The sporulation reached 6.13×108 conidia per cm2. The optimal harvest time was determined on the ninth day. In the production experiment with plastic reseau board as the carrier, the yield was 1200~2000×108 conidia per gram with water content 9.05～11.36% and germination rate>98%. The residue left on and collected the carriers contained 1.1～2.4×108 conidia per gram.An experiment of M. alternatus control was set with non-woven fabric bands impregnated with B. bassiana in different release frequencies. The results showed that the rates of dead trees increased 43.1% and 67.9%, respectively in the control plot and plot E where only one release of fungal band in the first year of two years, while the rates of others decreased 2.9%～38.6%, respectively. In the high frequency (2 release each year in the 2 years) release plot B the rate was the highest (38.6%). As compared with the control plot, all treatment plots except plot E relieved significantly (p﹤0.05), suggesting that the release of the fungal bands in the plots had effective control of M. alternatus and releasing frequency of twice a year was the best.The results of a biodiversity investigation in forest showed that the dominant groups were Lepidoptera, Orthoptera, Hymenoptera, Diptera, Coleoptera and Araneae similarly in the six different plots. The species numbers were equal or close in these groups.By analyzing indexes of biodiversity, it was suggested that the B. bassiana bands release in pine plantations didn't have obvious effect on biodiversity of the community. The results of the experiment of A. glabripennis control by the B. brongniartii and M. anisopliae showed that mortalities of A. glabripennis in the B. brongniartii plot and the M. anisopliae plot were 21.26% and 24.34%, respectively. The average lethal time in B. brongniartii plot, M. anisopliae plot and control plot was 10.38d, 17.16d and 23.28d, respectively.
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