新疆棉花黄萎病菌拮抗细菌的分离、筛选与鉴定

【背景】棉花黄萎病是由大丽轮枝菌(Verticillium dahliae Kleb.)引起的一种世界性病害,近年来对该病害的生物防治因具有环境友好和人畜安全的特性而倍受关注。【目的】筛选棉花黄萎病高效拮抗细菌并对其进行鉴定,为棉花黄萎病的生物防治扩充菌种资源。【方法】采用稀释涂布平板法分离细菌,并进行拮抗细菌的初筛和复筛,通过形态特征、生理生化特征和16S rRNA基因序列分析对筛选到的细菌进行鉴定,确定其分类地位。【结果】初筛分离到535株对病原菌具有拮抗作用的细菌,并选取了108株拮抗细菌进行复筛,最终筛选到了4株优势拮抗细菌。通过形态观察、生理生化特征和16SrRNA基因序列分析,将菌株BHZ-29、SHT-15、SHZ-24和SMT-24分别鉴定为贝莱斯芽孢杆菌(Bacillusvelezensis)、枯草芽孢杆菌斯皮兹仁亚种(Bacillus subtilis subsp. spizizenii)、萎缩芽孢杆菌(Bacillus atrophaeus)和香草芽孢杆菌(Bacillus vanillea)。【结论】获得了4株高效拮抗细菌,并且首次报道了香草芽孢杆菌对棉花黄萎病菌具有抑制作用。

Isolation, screening and identification of antagonistic bacteria against Verticillium dahliae Kleb. in Xinjiang

Background] Cotton Verticillium wilt, caused by Verticillium dahliae Kleb., is one of the most devastating diseases. Biological control has been drawn more and more attention in recent years for its safety to environment, human and animal. Objective] In order to expand strain resources for biological control of cotton Verticillium wilt, we urge to isolate, screen and identify highly efficient antagonistic bacteria against Verticillium dahliae Kleb. Methods] The bacteria were isolated by spread plate method, the antagonistic bacteria were obtained by primary screening and subsequent screening. Strains were identified based on morphological, physiological and biochemical characteristics and 16S rRNA gene sequence analysis. Results] 535 strains of antagonistic bacteria were primarily isolated and 108 strains of them were further tested. Finally, four highly efficient antagonistic bacteria were screened. Based on morphological, physiological and biochemical characteristics and 16S rRNA gene sequence analysis, strains BHZ-29, SHT-15, SHZ-24 and SMT-24 were preliminarily identified as Bacillus velezensis, Bacillus subtilis subsp. spizizenii, Bacillus atrophaeus and Bacillus vanillea, respectively. Conclusion] Four highly efficient antagonistic bacteria were obtained and the inhibition effect of Bacillus vanillea on cotton Verticillium wilt was reported for the first time.