一株抗烟草赤星病解淀粉芽孢杆菌的筛选及鉴定

Screening and identification of an antagonistic Bacillus amyloliquefaciens against tobacco brown spot

从土壤中分离出82株细菌,通过平板对峙法初筛和双层平板法复筛,筛选出对烟草赤星病菌有较强拮抗作用的细菌B11菌株,其无菌发酵液对烟草赤星病菌(Alternaria alternata)的抑菌带达到26.55mm.对B11菌株进行生理生化和分子鉴定,结果表明B11菌株生理生化特征与Bacillus amyloliquefaciens最为接近;16SrRNA基因序列分析结果表明该菌株与B.amyloliquefaciens(NR-116022)聚类呈一支,同源性为99%,因此把该菌株鉴定为解淀粉芽孢杆菌(B.amyloliquefaciens).进一步研究表明B11菌株对几种植物病原真菌的生长均有抑制作用.

82 bacterial strains were obtained from soil.By plate confrontation method and preliminary screening and double plate screening,strain B11 was screened to have the strongest inhibition against Alternaria alternata.The inhibitory zone of aseptic fermented liquid against A.alternatareached 26.55 mm.Physiological,biochemical and molecular identification of B11 strain were carried out.The physiological and biochemical characteristics of B11 strain were closest to that of Bacillus amyloliquefaciens.16 SrRNA sequence analysis of strain B11 showed that B.amyloliquefaciens（NR-116022）clustering and strain B11 became a branch（99% similarity）.So,it was identified as B.amyloliquefaciens.Further studies showed that B11 strain had some inhibitory effects on several plant pathogenic fungi.