| In order to control forest pests effectively by using entomopathogenic fungi, and take full role of the fungi in the control of forest pests in integrated pest management, the pilot prodution technique of a newly developed formula of fungal insecticide, nonwoven fabric bands impregnated with Beauveria bassiana and field trials against the black longicorn beetle, Spondylis buprestoides and the pine sawyer, Monochamus alternatus with the bands, were studied in the present thesis. In addition, recovery study on released B. bassiana strains by molecular marker was also made to provide evidence for rational application. Degradable nonwoven fabrics were adopted to make the bands, juice of boiled wheat bran juice and commercial sugar were used as medium. Under the condition of 25℃ and 95-100%RH in an incubation system, sporulation of B. bassiana was up to 3.99×108 conidia/cm2 and that of Metarhizium anisopliae var. anisopliae up to 2.77×108 conidia/cm2. The bands impregnated with M. anisopliae var. anisopliae were used together with an attractant against the black longicorn beetle, Spondylis buprestoides in different ways. The trapped beetle adults which were forced to touch the bands in traps (Treatment 3) were infected by 70%, while the caged treatments in dosages of 60 bands (Treatment 1) and 90 bands (Treatment 2), respectively, in 0.67 hm2, each around one tree trunk, the infections due to air-borne conidia were both over 35%, not significantly different each other, but both significantly higher than that in the control. The beetle adults trapped were reared in laboratory. The infection in Treatment 3 reached 63.3%, while those in Treatment 1 and 2 were 48.7 and 53.1%, respectively, not significantly different each other, but both higher than that in the control. The result showed obvious potential of such combined use against the black longicorn beetle. Field trials against the pine sawyer, Monochamus alternatus with the fungal bands of M. anisopliae var. anisopliae made no impact on the pine sawyer population and only 1.9% was be infected, suggesting that the pine sawyer was unsuitable for use of M. anisopliae var. anisopliae bands. In all the treatment of B. bassiana, M. anisopliae, the combined use of the 2 fungi, and the control, the infections by B. bassiana were all between 9.3-11.7%, with no significant differences. In addition, the differences were also not significant between the treatment and control plots of oviposition scars and average surviving time, suggesting that air-bore conidia did not have important effect on the sawyer population although they affected large area. In laboratory, however, the infection of sawyer adults from the treated B. bassiana field, was significant higher 38.1% than that 22.4% from the control area, and the surviving time of the sawyer from B. bassiana treatment plot was also significantly shorter than that from the control plot, suggesting that through touched and air-borne conidia the treatment of B. bassiana bands did impact the sawyer population significantly. One hundred and fifty-eight insect cadavers were collected in the plots treated with the fungi. Eight species of entomogenous fungi of 3 genera including B. bassiana were found. The large amount of cadavers maintained a certain inoculum of entomogenous fungi in the pine plantation. A percentage of 81.01% of the total cadavers was infected by Beauveria spp., and Beaveria spp. prevailed in community of entomogenous fungi. Among them there were 117 isolates (74.05%) of B. bassiana; and 28 isolates (17.72%) of Paecilomyces spp. The community of entomogenous fungi was important for sustainable control of forest pests. Based on rDNA group I intron, 106 B. bassiana isolates were divided into 10 groups. The group which the release isolate(Bb202) belonged to included 57 isolates, accounting for 53.2% of the total isolates. In 38 B. bassiana isolates from cadavers of the target pest, the pine sawyer, 30 of them belonged to the same group as released isolate (Bb202), accounting for up to 78.94%;on this basis, the 39...
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