【摘要】 目的:分离对玉米小斑病菌(Bipolaris maydis)有拮抗作用的内生菌株并进行菌种鉴定。方法:经表面消毒用碾碎法从水浮莲(Pistia stratiotes L.)中分离内生菌,用平板扩散法筛选出对玉米小斑病菌(Bipolaris maydis)有明显拮抗作用的内生菌株XJ-PL-YB-50,利用16SrDNA通用引物对其基因组DNA进行扩增,并测序得到XJPL-YB-50的部分16SrDNA序列,GenBank接收号为EU262981。经Blastn调出与菌株16SrDNA同源的序列,用软件MEGA3.1按照Neighbor-Joining方法构建16SrDNA系统发育树。结果:XJPL-YB-50的主要生理生化指标与Bacillus subtilis相符,与Bacillus subtilis AB271744处于同一分支,相似性为100%,G+Cmol%为47.7%。结论:水浮莲内生菌XJPL-YB-50对玉米小斑病菌有明显拮抗作用,并最终鉴定为枯草芽孢杆菌Bacillus subtilis。更多还原

【Abstract】 Objective:To screen the endophytic baceria had antagonistic action against Bipolaris maydis and identify. Method: Endophytic bacteria were isolated from leaves of Pistia stratiotes L.through surface-sterilization,and one of them named XJPL-YB-50 was screened had antagonistic action against Bipolaris maydis through agar diffusion. The part 16S rDNA was PCR using universal primer and sequenced. The accession of GenBank is EU262981. The 16S rDNA phylogenetic tree was constructed by comparing with published 16S rDNA sequences of the relative bacteria species using Neighbor-Joining. Result: According to the phylogenetic analysis, It’s main physiological and biochemical results accord with Bacillus subtilis’s, and AB271744 was the closest relative with 99% sequence similarity, G+C mol% is 47.7%.Conclusion: Pistia stratiotes L.endophytic baceria XJPL-YB-50 had antagonistic action against Bipolaris maydis, it was identified as Bacillus subtilis XJPL-YB-50.更多还原