棉花黄萎病高效拮抗菌XJUL-6的筛选鉴定及其特性研究

为探讨棉花黄萎病高效拮抗菌的拮抗机制,从新疆有毒植物焮麻(Urtica cannabina L.)中筛选出一株对棉花黄萎病具有较强抗性的内生菌XJUL-6,对其生物学特性进行初步研究,结果表明,36℃~38℃为最适生长温度,pH6~8为最适生长pH值。根据其形态特征、生理生化检测、16S rDNA、(G C)mo1%,将其鉴定为蜡状芽孢杆菌,XJUL-6的获得为进一步的研究棉花黄萎病高效拮抗菌的拮抗机制提供了实验材料。

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.