一株拮抗姜瘟青枯假单胞杆菌的链霉菌的分离及鉴定

从生姜田土中分离到一株对姜瘟青枯假单胞杆菌(PseudomonassolanacarumSmith)有强拮抗作用的链霉菌菌株SR 11,研究拮抗性表明,对革兰氏阳性细菌、革兰氏阴性细菌以及多种病原真菌均有很强的抑制作用。对该菌株进行形态特征、培养特征、生理生化、细胞壁组分分析及16SrDNA序列分析。基内菌丝无横隔、不断裂,气生菌丝多分枝;孢子丝波曲至螺旋形,孢子椭圆形,表面光滑。细胞壁化学组分Ⅰ型,糖型C。在培养成熟后,气丝变为灰色,可闻到浓烈的土味。以16SrDNA序列为基础构建了包括13株相关种属细菌在内的系统发育树,其中,与12个模式链霉菌株的16SrDNA序列的同源性为96 5 %～98 3%。

Isolation and identification of a Streptomyces strain against ginger bacterial wilt caused by Pseudomonas solanacarum Smith

Streptomyces SR-11 was isolated from the soil of ginger in Sichuan Province against ginger bacterial wilt caused by Pseudomonas solanacearum Smith. It had distinctively inhibitive effect on gram-positive bacterium, gram-negative bacterium and some kinds of pathogenic fungi. It's morphological, cultural physiological, biochemical characteristics, chemotaxonomy and 16S rDNA sequences analysis were studied. The substrate mycelium have no partition, the aerial mycelium are ramose; The spore-bearing filaments are spiral, the spores are oval and the surface are smooth. Cell wall type I, Sugar type C. When SR-11 is matured, the aerial mycelium are gray and the strain can give out an earthy smell. A phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the related bacteria species. In the phylogenetic tree the overall similarity value between strain SR-11 and 12 type Streptomyces sp are 96.5-98.3%.