兰花枯萎病拮抗细菌的筛选与鉴定

Screening and Identification of Antagonistic Bacterium against Colletoichum wilt

为筛选对兰花枯萎病病原菌尖孢镰刀菌具有拮抗作用的芽孢细菌,从各地采集的土样中分离获得的237株芽孢杆菌进行初筛、复筛,最终从衡水饶阳县棉田的土样中筛选出的芽孢杆菌3A3-15,对病原菌有较强的抑菌活性,且抑菌谱广。结合形态学观察、生理生化试验,根据16S rDNA序列相似性分析,此菌株与Bacillus velezensis标准菌株CR-502的16S rDNA序列相似度达99.92%,因此,鉴定拮抗菌株3A3-15为Bacillus velezensis。

In order to obtain antagonistic bacteria against Fusarium oxysporium,237 bacillus strains were isolated and screened from soil samples of different districts.A bacillus strain 3A3-15 collected from cotton soil of Raoyang County in Hengshui was obtained via preliminary screening and secondary screening.It had strong and broad-spectrum inhibition capability.We characterized the strain 3A3-15 by morphological and culture features observation,physiological and biochemical experiments,and 16S rDNA sequence analysis.As the similarity of the 16S rDNA sequences between strain 3A3-15 and the type strain CR-502 was up to 99.92%,the strain 3A3-15 was finally identified as Bacillus velezensis.