瓜类枯萎病拮抗放线菌T8-41的鉴定

目的]为阐明1株拮抗放线菌菌株的分类地位提供依据。方法]以从东北地区蔬菜保护地土壤中分离的1株拮抗放线菌菌株T8-41为试材,分析其形态和培养特征、细胞壁成分和生理生化特性。经PCR扩增后,对其与相关菌株的16S rDNA进行同源性分析和聚类分析。结果]拮抗菌株T8-41属于典型的链霉菌属菌丝形态。其细胞壁中含有L-DAP和甘氨酸,细胞壁类型为I型。该菌可利用D-木糖、L-鼠李糖、D-果糖、蔗糖、棉子糖、葡萄糖、D-甘露醇和肌醇,但不利用乳糖。可以初步鉴定为绿产色链霉菌。T8-41菌株的16SrDNA全长为1 465 bp,与绿产色链霉菌相似性达99%。结论]链霉菌T8-41属于青色类群的绿产色链霉菌,可将其定名为绿产色链霉菌T8-41(S.viridochromogenes T8-41)。

Identification of Antagonistic Actinomycete T8-41 against Fnsarium Wilt from Melon

Objective] The research aimed to provide basis for clarifying the taxonomic status of a strain of antagonistic actinomycete.Method] With a strain of antagonistic actinomycete T8-41 isolated from the soil of vegetable protected land in the northeast of China as tested material,its morphology and culture characteristics,cell wall composition,physiological and biochemical characteristics were analyzed.After PCR amplification,the homology anslysis and the clustering analysis of 16S rDNA between it and the related strain were made.Result] The antagonistic actinomycete T8-41 belonged to typical mycelial morphology of Streptomyces.There were L-DAP and glycin in its cell wall whose type was I type.This strain could make use of D-xylose,L-rhamnose,D-fructose,saccharose,raffinose、glucose,D-mannitol and inositol,but it couldn't make use of lactose.It was prelimanrily identified as Streptomyces viridochromogenes.The whole length of 16S rDNA of strain T8-41 was 1 465 bp and its similarity with S.viridochromogenes reached 99%.Conclusion] Streptomyces T8-41 belonged to cyan group of S.viridochromogenes and it could be named as S.viridochromogenes T8-41.