1株烟草青枯病拮抗内生细菌的分离及鉴定

为了筛选具有生防价值的拮抗烟草青枯雷尔氏菌的内生细菌,从湖南长沙、永州、郴州烟草青枯病发病区的健康烟株采集茎秆,采用稀释平板分离法获得150个内生菌株.抑菌结果表明,21个内生菌株对烟草青枯雷尔氏菌2316菌株有拮抗效果,占总菌株数的14.0％.拮抗菌株中,F1菌株24 h对烟草青枯雷尔氏菌株2316抑菌圈直径达6.5...

Isolation and identification of an antagonistic endophytic bacteria strain against tobacco bacterial wilt

Tobacco bacterial wilt (TBW) is caused by bacterium Ralstonia solanacearum. To effectively develop microoganisms for biocontrol of TBW, 150 strains of tobacco endophytic bacteria from the stems of the health plant at TBW areas in Chenzhou, Yongzhou of Hunan were obtained by the dilution method. Antagonistic test showed 21 of the 150 strains, accounting for 14%, had antagonistic effects against R. Solanacarum. Among the 21 strains, strain F1 showed the best antagonistic effect with the diameter of inhibition zone against tobacco R. solanacarum strain 2316 at 24 hours of 6.5 mm, and showed a wide antimicrobial spectrum including five kinds of pathogenic fungi such as Sclerotium rolfsii and five kinds of pathogenic bacteria such as Xanthomonas campestris pv. citri. Based on analysis of the morphological, physiological, and biochemical characteristics and the 16S rDNA phylogeny, strain F1 was identified as Bacillus mojavensis.