| The biocontrol fungi, Trichoderma spp, which is one of the most promising fungal species used to control plant diseases, has great potential in the agricultural production. In order to put these fungi into application, this thesis mainly does some research on its biocontrol mechanism and applicaton results on the farm. The research mainly includes: the isolation and morphological identification of Trichoderma species; the parasitical specialism of Trichoderma sp. on pathogeny fungi; selecting and greenhouse disease prevention effect testing of Trichoderma species for gray mold disease of strawberry; relativity analysis between prevention result and biological or biochemical characteristics; condition improvement of solid fermentation; greenhouse appliance for control of gray mold disease and white powder disease. also,we do some elementary research on the verdure maintance of strawberry. Twenty-five isolates of Trichoderma species from different areas around Anhui Province were chosen through their culture characteristics and thirteen of them were morpho -logically identified, among which 6 Trichoderma viride, 5 Trichoderma harzianum and 2 Trichoderma koningii. To investigate different resistant efficiency of differrent Trichoderma species on different pathogenic fungi, parasitical specialism of Trichoderma species was studied through dual culture. The result showed that Trichoderma species have great specialism in their parasitical processes. So we'd better use different Trichoderma species for different diseases, to get the best control results. For the control of gray mold disease in greenhouse around Hefei city, Trichoderma W-09 was selected through synthetic ways of dual culture and isolated leaves dual inoculation. The strain has some excellent traits such as high growth rate, high control result, high temperature durance and be convenient to produce spores under industrial conditions. The greenhouse testing result showed that it had a control rate of 66.9%. The relativity analysis of Trichoderma between inhibition rate and biological or biochemical characteristics, is an elementary research for strain screening and effect improvement. According to the diverse control results of different Trichoderma species in the control of gray mold disease, this thesis focused on five biological indexes: growth rate, antibiotic level, ?-1, 3-glucanase, chitinase and proteinase. And then relativity coefficient was calculated for each of the above. The result showed that antibiotic level had highest relativity coefficient with inhibition rate amounting to 0.97, and followed by ?-1,3 –glucanase to 0.84, growth rate to 0.6 ,induced chitinase to 0.5 and the least proteinase. In other words, antibiotic level was the most effective on the inhibition rate of Trichoderma to pathogenic fungi and proteinase the least. In terms of the solid-state fermentation for the purpose of industrial production, this thesis mainly selected the best nutritional materials for liquid fermentation and solid-state fermentation. the result showed that sucrose was the optimum carbon source and corn flour the best nitrogen source for liquid fermentation. Further more, an optimal medium was determined through an orthogonal test: corn flour 3%,sucrose 4%,K2HPO4 0.1%, PH: 7.0 and the best culture temperature: 25℃. The solid-state fermentation substances of Trichoderma W-09 were primarily selected with the ferment of 4-single and 5-mixed solids. The results showed that corn flour and corn flour+sawdust,wheat bran medium+corn flour were achieved with the most quantities of sporulation quantities. so choosing the corn flour,sawdust,wheat bran and grain shells as four components with three different weight levels for each component, the orthogonal design was tested. Through fermentation tests of the all 9 orthogonal prescriptions of substrates, the best selected solid components was achieved, corn flour:sawdust:wheat bran:grain shells =3:1:1:3。 The field trials of Trichoderma W-09 against gray mold disease and white powder disease of strawb...
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