Environment Investigation Of Flammulina Vel Utipes Factory Cultivation And Biological Control Of Soft Rot Of Flammulina Velutipes

In the factory cultivation process of Flammulina velutipes, the environmental health has the important influence on of the production Flammulina velutipes. The method of gravity-sedimentation flat-plate was used for determination of floating microbial content in air in each clean area, and then with reference to the cleanliness level standard of pharmaceutical industry, the environment cleanliness level of clean area and change of microbial community were analyzed. The results showed that the clean area of factory cultivation of Flammulina velutipes (cooling chamber, inoculation room, culture room) were higher cleanliness level in the test period. In addition, pollution rate has correlation with the number of mould. The rate of pollution is the highest in the mold maximum number, so it was need to cooling, dust removal and disinfection to reduce the number of mould and the rate of pollution.In the cultivation process of Flammulina velutipes, we found that there is a soft rot fungi which has great harm to the production of Flammulina velutipes, was known as the white mildew. Through purification, morphology and ITS sequence analysis, this fungi is Cladobotryum varium.The prevention and treatment of Cladobotryum varium mainly depends on chemical drugs in edible fungi production. From the biological point of view, one strains of antagonistic bacteria against Cladobotryum varium were obtaioned by means of Duel-culture method and named it B43-1. The strian was identified by observation of the strain’s morphology characteistics, physiological and biochemistry experiment,16SrDNA and gyrA sequence analysis. The identification results indicated the strain B43-1is Bacillus amyloliquefaciens.The lipopeptides produeed by Bacillus amyloliquefaciens included surfactin, iturin and fengycin. It was found that fermentation supernatant fluid of Bacillus amyloliquefaciens B43-1has the inhibition to Cladobotryum varium. Through the acid precipitation, methanol extraction, silica gel column chromatography, HPLC purification and identification of mass spectrometry, and combined with specific gene ituC sequencing analysis, preliminary results was thought that iturin C was the main lipopeptides from Bacillus amyloliquefaciens B43-1to inhibit Cladobotryum varium.The results of6kinds of chemical fungicide efficacy show that metalaxyl mancozeb, thiophanate methyl, mancozeb and thiram had the best inhibition effect to Cladobotryum varium, but metalaxyl mancozeb, mancozeb and thiram had toxicity to mycelium of Flammulina velutipes, and thiophanate methyl almost had no toxicity to it. The crude extract of Bacillus amyloliquefaciens B43-1fermentation supernatant fluid can effectively inhibit growth of Cladobotryum varium. Through the mixed experiment of crude extract and thiophanate methyl found that it still can improve the inhibition effect to growth of Cladobotryum varium under certain circumstance reduce the concentration of thiophanate methyl.