| Based on the understanding of control strategies on grasshopper all over the world, the study on the entomopathogenic fungus, Metarhizium anisopliae, was summarized. The contents including the aspects are as follows: the study on Metarhizium anisopliae, general situation was expatiated with five aspects, taxonomy and systematic research of Metarhizium; aggressive and pathogenic mechanism, induced mutation for microbial breeding to enhance virulence of M.anisopliae, production of M.anisopliae; expounded the locust disaster, the breakout reasons, as well as prevention measures combined with the present of locust disaster all over the world; expatiated that how to identify formulation, measure toxicity and the present study on M. anisopliae oil formulation all over the world. At first, the normally dead body of locusts were collected from local grassland in Xinjiang for isolation. From the locusts of Dociostaurus kra kra, an entomopathogenic fungus was obtained and named identified as M. flavoviride. In order to improve toxicity, the study mutation of M.anisopliae from the Center for Microbial Culture Collection in Chinese Academy or Agricultural Science, was conducted. The mutant conditions were decided that the optimal concentration of NTG 0.02g/l, the optimal duration 60 min, the optimal irradiation of UV 20min, according to 70-80% mortality of the mutant strain which was firstly celected in the way of single colony and transparent circle, and then measured the activity of Pr1 from the strain, as well as related to toxicity of Metarhizium, and measured by indoor bioassay. Six high virulent mutants, FCT10.10, FCC6.94, FCC6.2, FCC6.6, FCT10.36, FCC6.38 were singled out, meanwhile LT50 measured as 4.05d, 4.41d, 5.91d, 6.00d, 6.3d, 6.45d, respectively. Finally FCT10.10 was selected as the highest virulent strain for production. Compared with the six selected mutant strains of M.anisopliae, the isolated strain of M.favoviride, there were some different characteristics in colony as follows: original Metarhizium and 6 mutant strains turned while into olive green and dust-color at last; in the middle of the separated colony turned white into dust-yellow green ,and to light dust-olive in the end. After mearsurating the growth capacity of the different strains, the results were showed that the 8 strains had the same growth level,and with the culturing time increasing ,diameter appeared lineaity raising trend; the results were showed that the electrophoretic patterns of proteins were significantly different, and the different mutagened strains had respectively pattern through electrophoretic bands and patterns of the soluble proteins from 8 strains banding pattern . The medium oil and activator in Metarhizium were primarily selected, according to the bourgeon rate of the spores. Of 8 selected medium oil, the M. anisopliae spore had the highest bourgeoning rate. Considering stronger viscosity of the salad oil, it went against on sufflating automatically, we mixed salad oil and kerosene as 1:3 to the insufflation medium off spore ponder of FCT10.10; in three auxiliary agent,activator A.B, medium oil's dissolvtion were worse, and they couldn't help the spore bourgeon; the bourgeoning rate of the spore was highest when activator C's concentration was 50ppm, so activator C was pitched on; In choosing from UV-protector, UV-4﹕10, whose spore germination rate was the highest, was picked out to regard as UV-protector. On the basis of compatible ratio, the formulation was wade by Metarhitium spore powder to determine the indoor bioassay. After a series of the analysis, we can calculated the regress equation is y=-14x-23.25 and R=0.977 and LT50 was 5.23days.
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