[Characteristics and identification of an antagonistic XJUL-6 against cotton verticillium wilt].

In order to probe into the antagonistic mechanism of bacteria against Verticillium dahliae kleb., twelve endophytic bacterial strains were isolated from the Urtica cannabina L. in XinJiang. Through antagonistic experiments, the antagonistic charts of the twelve endophytic bacterial strains against eleven crop diseases have been obtained, respectively, and the XJUL-6 which has higher antagonistic activity against Verticillium dahliae kleb. was screened from the endophytes with the Joan-board diffusion method. The optimum growing temperature range of XJUL-6 is 36 degrees C to approximately 38 degrees C, and the optimum growing pH is pH6-8. Phylogenetic analysis of the XJUL-6 based on comparison of 16S rRNA sequence revealed that it is closely related to Bacillus cereus p221 with 98% identity. Moreover, the (G + C) mol % content of the genomic DNA was 38.84 mol % for XJUL-6. According to the observation of the morphology, the study of the physiological and biochemical, 16S rDNA and (G + C) mol % content, the XJUL-6 was identified as a new members of the species Bacillus cereus. The XJUL-6 will offer potential material for studying the mechanism of bacteria against verticillium dahliae kleb. in cotton.