| In this paper, two antagonistic microorganisms were isolated and identified from pathogenic soil of linseed, and their antibacterial mechanism, antagonistic substance as well as wilt control effect were also conducted. The results are as follow:1. A bacillus (XJ2-20) and an actinomycete (GS2-1) were isolated from pathogenic soil of linseed. The results showed that these two strains had very good antibacterial effects against those 151 fungi isolated from different provinces, China were evaluated.2. These two strains can produce some antagonistic substances, which effectively influence mycelium growth and spore bourgeoning of the Fusarium oxysporum f. sp. lini.3. After mixed in different volume of fermentation filtrate, the control effect of XJ2-20 had an obvious increase of 56.3%, also, the control effect of GS2-1 even suffered a higher rate of 68.8%. 4. XJ2-20 belongs to Bacillus sub tilis. Identification of GS2-1 is still under study.5. The most suitable (NH4)SO4 concentration of obtain crude protein was 70%. The optimal pH of the protein is 7 and it is more sensitive to acid. The protein is also sensitive to heat and trypsin.Microwave was used to dispose fermentation filtrate of GS2-1. The optimal pH of fermentation filtrate is 9. When the temperature is below 80℃, the physical and chemical character of the filtrate is stable and it is insensitive to UV. The substance can easily dissolve in medium-polar solvent chloroform so that it can be extracted by chloroform.6. For XJ2-20, the result showed a best culture time of 5 days, an optimal volume of 50-100mL/300mL erlenmeyer flask, an appropriate pH of 7.2, a good temperature of 29℃and a suitable medium of LB liquid medium. While for GS2-1, the culture time is from of 6-9 days, the best volume of media is 100mL/300mL erlenmeyer flask, the optimal pH is also 7.2, the suitable culture temperature is between 29℃to 32℃and the most appropriate medium is the 2nd improvement medium.
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