[Isolation and identification of a Bacillus amyloliquefaciens YB-3 against Rhizoctonia solani].

OBJECTIVE: An antagonistic bacterial strain YB-3 against Rhizoctonia solani was isolated from soils. METHODS: Antagonistic strains were isolated by a reporter strain method. YB-3 was identified based on morphology observation, physiological and biochemical characterizations, Biolog, G + C content and 16S rDNA sequence analysis. The antagonistic spectrum and the properties of the inhibitor produced by Bacillus amyloliquefaciens YB-3 against plant pathogenic fungi and bacteria were investigated by means of plate two-way cultivation and disc diffusion method. RESULTS: The strain YB-3 against Rhizoctonia solani was identified as Bacillus amyloliquefaciens. The antagonistic results showed that it had distinctively inhibitive effects on 14 pathogenic fungi and 7 bacteria. In addition, it also had inhibitive effects on strains from genus Bacillus to which YB-3 belongs. Antagonistic properties of B. amyloliquefaciens YB-3 was thermostable, acid resistant, and protease sensitive. CONCLUSION: Bacillus amyloliquefaciens YB-3 was isolated and characterized which had distinctively inhibitive effects on Rhizoctonia solani and had broad-spectrum, highly efficient to plant pathogens.