棉花黄萎病生防内生芽孢杆菌LH-L3的分离鉴定

摘要

[目的]获得能够防治黄萎病菌的棉花内生芽孢杆菌.[方法]将棉株组织研磨液80℃加热后,采用涂板法分离内生菌,将对大丽轮枝菌强致病力菌株Vd084拮抗效果最好的菌株,依据菌体形态、生理生化特征、16SrRNA、gyrB和rpoB基因序列分析进行鉴定,并以盆栽试验确定其对棉花黄萎病的防效.[结果]分离到61株芽孢杆菌类似菌,其中17株能拮抗大丽轮枝菌.复筛得到1株拮抗活性较高、抑菌谱较广的菌株LH-L3.该菌株被鉴定为甲基营养型芽孢杆菌.与无菌水对照相比,用106 mL-1的LH-L3菌液浇灌3次的棉花出苗率、株高、根长、地上以及地下部分鲜物质质量分别提高42.85％、10.24％、23.83％、10.05％、97.62％,对棉花黄萎病的防治效果达到85.24％.[结论]菌株LH-L3有较好的促生长和棉花黄萎病防治的效果,具有进一步开发应用潜力.%[Objective] The aim of this study is to obtain endophytic Bacillus with control effect on cotton Verticillium wilt.[Method] The cotton tissue grinding liquid was heated at 80 C,and spread onto the Luria-Bertani ager medium.The strains with better inhibitory effects on Verticillium dahliae Vd084,a strain with strong pathogenicity,was identified by the morphology,physiological and biochemical traits as well as 16S rRNA,gytB and rpoB sequences,and its control effect on cotton Verticillium wilt was determined by pot experiments.[Result] 61 similar Bacillus strains were isolated from cotton plants.Among them,17 strains could inhibit Verticillium dahliae Vd084.A strain named LH-L3 with a relatively higher antagonistic activity and a broad inhibition spectrum was obtained in the second screening.LH-L3 was classified into Bacillus methylotrophicus.Compared with the control,the emergence rate,plant height,root length,fresh weight of aerial part and underground part of cotton with 106 mL-1 LH-L3 suspension drenching for 3 times increased by 42.85％,10.24％,23.83％,10.05％ and 97.62％,respectively.And control effect on Verticillium wilt was 85.24％.[Conclusion] LH-L3 had good growth promotion and Verticillium wilt control effects and showed good potential for biological control.