Abstract:
Antagonistic bacterial strain BDT-25 was isolated from the rhizosphere.Antagonistic test showed that the strain showed significant inhibitory effect on mycelium growth and microsclerotia formation of Verticillium dahilae Kleb.Further inhibition tests of strain BDT-25 were conducted on different plant fungal pathogens.Results showed that strain BDT-25 also showed significant antagonistic to other 10 pathogens including Fusarium oxysporium f.sp.vasinfectum,Rhizoctonia solani et al.Identification of strain BDT-25 was carried out through physiological and biochemical testing,the result confirmed that it is Bacillus subtilis.Antagonistic activities of strain BDT-25 were evaluated under different culture conditions.The result showed that the strain could produce more antifungal substance under the optimum condition(cultured in NB broth at 170 r/min for 48 hours under 28℃ and,pH7.0).Precipitates of the fermentation liquid from strain BDT-25 were collected by 80% saturation ammonium sulfate and showed significant inhibitory effect on mycelium growth of V.dahilae.The antifungal substance from strain BDT-25 was sensitive to heat,Proteinases K,Trypsin and Pepsin,but was not sensitive to RNAase.According to the result,the antifungal substance could be approved as antifungal protein.
Key words:
Verticillium dahilae,
antagonistic bacterium,
identificat ion,
antifungal protein
CLC Number:
SUN Yao, MA Ping, ZHU Bao-cheng, LI She-zeng, LU Xiu-yun. Identification and Production Condition of the Antifungal Protein from Antagonistic Bacterium BDT-25 Against Verticillium dahliae[J]. ACTA AGRICULTURAE BOREALI-SINICA, 2006, 21(6): 119-123. doi: 10.3321/j.issn:1000-7091.2006.06.029.