| The pathogens which were identified as Botrytis cinerea were isolated from plants such as strawberry,grape and capsicum in greenhouse in Daxin near ya'an city.59 strains of Gliocladium virens were isolated from the different crop soil in the suburbs of ya'an. According to the derivation, the speed of hyphal growth and the colour of colony, 30 strains of Gliocladium virens were picked out to make further research.The results of studies on biological characteristics of 6 strains of Botrytis cinerea come from different crops showed that 6 strains of Botrytis cinerea could grow from 5℃to 30℃while the best temperature for hyphal growth was from 17℃to 23℃and for sporulation was from 20℃to 25℃. Conidiophores could germinate from 5℃to 30℃, and the suitable temperature was from 20℃to 25℃. The Mycelium could vegetate from pH4 to pH11 and the best pH for hyphal growth, sporulation and conidiophores germination was pH6. Dark condition was advantageous for hyphal growth and sporulation, while illumination was advantageous for conidiophores germination. Culture medium PDA and PSA can better accelerate hyphal growth and sporulation. The best carbon source for hyphal growth was glucose and for sporulation was cane sugar. The best amino acid for hyphal growth was aspartic acid and for sporulation was glutamic acid. The best ratio for carbon and azote is 30:1. Conidiophores could not germinate under the humidity of 80%, while had a highest germinated rates in the water.Temperature, pH and types of culture medium were the major factors for hyphal growth and sporulation. Tables of 3 factors and 3 levels were selected for the orthogonal experiment. The results showed that: the combinatorial conditions of pH6, 20℃and culture medium of PSA were the best conditions for hyphal growth and sporulation. The infection degrees of these 3 factors for hyphal growth and sporulation were: temperature > types of culture medium > pH.The biocontrol potential of 30 selected strains of G. virens was tested in the present study. The result showed that the rate of hyphal growth of 30 strains were over 25mm/d, and particularly the growth of strain G27 was the fastest, the rate of which was 32.2mm/d.In the pair culture experiment,there were 24 strains of Gliocladium virens, the suppression rates of which against the pathogen hyphal growth were over 60%. In the experiment of non-volatile metabolite,6 strains had the restrained rates over 20% when their fermented product was sterilized by bacteria filter, and those of G17 was the highest. However, the effects of fermented product sterilized by steam sterilizer. In this case, the restrained rates of all the strains were under 20%, while G13 had the highest rates of 23.34%.The rates of volatile metabolized produce were lower than non-volatile metabolized produce, while the G13 had the highest rates of 18.67%.The efficiencies of several fungicides to Botrytis cinerea showed that: all the tested funggicides were suppressive to Botrytis cinerea. The 50% procymidone WP had the highest inhibition rates, of which the EC50 was 0.0283μg/ml, and its comparatively virulence index was 1.2×10-3. The EC50 of 70% Mancozeb WP was 1.6634μg/ml, and the comparatively virulence index of it was 0.72×10-1, which had showed strong inhibiting effects. The EC50 of 50% carbendazol WP was 23.178μg/ml, which was the highest in this experiment.The results of disease control in the pot experiment showed that: after 16 days, the incidence of diseases of the treatment of blank antitheses was the lowest, 5.6%. The incidence of diseases of the treatment of Mancozeb+B. cinerea was 9.75%, and the Gliocladium virens+B. cinerea was 14.6%, which was higher than the former. After 20 days, the incidence of diseases of blank antitheses was 68.7%. The incidences of diseases of Mancozeb+B. cinerea and Gliocladium virens+B. cinerea were 15.5% and 23.4%. The controling effect of Mancozeb+B. cinerea was 77.4%, which was higher than 66.1 % of Gliocladium virens +B. cinerea.
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