通过16SrRNA序列比对、培养特征观察及生理生化特性测定,对一株烟草内生放线菌Y12进行了鉴定。结果表明:Y12菌株与白浅灰链霉菌亲缘关系最近,同源性达99%。Y12菌株气生菌丝白色至暗灰色,无可溶性色素,可使明胶液化,牛奶胨化,不产生黑色素和H2S,利用葡萄糖能力最强,利用蔗糖能力最弱。综合鉴定表明Y12菌株为白浅灰链霉菌(Streptomyces albogriseolus)。 Through a 16S rRNA sequence alignment, culture characteristics and physiological and biochemical characteristics of a tobacco endophytic actinomycetes Y12 were identified. The results showed that Y12 strain has the closest genetic relationship with Streptomyces albus, 99% homology. Y12 strain aerial mycelium white to dark gray, no soluble pigments, gelatin liquefaction, peptonization of milk, does not produce melanin and H2S, the ability to use glucose the strongest, the weakest use of sucrose. Comprehensive identification showed that the Y12 strain was Streptomyces albogriseolus.