黄瓜苗根围拮抗细菌X3的分子鉴定

采用生理生化、Biolog和16S rDNA分子鉴定3种不同方法，对抑制黄瓜苗期猝倒病病原真菌的细菌菌株X3进行了鉴定．生理生化鉴定显示该菌株为Pseudomonas aeruginosa；而Biolog鉴定显示其为P．spinosa；进一步对该菌株作16S rDNA基因的测定与分析，表明其与已报道的P．aeruginosa 16S rDNA具有93．7％的同源性，二者在所建系统发育树中处于同一分枝，据此确定该菌株为P．aeruginosa。

Identification on an antagonistic rhizobacterium X3 from rhizosphere of cucumber

Classical physiological and biochemical methods, Biolog, and 16S rDNA analysis were used to identify the strain X3 which could control cucumber seedling damping-off. Physiological and biochemical identification showed that it belonged to Pseudomonas aeruginosa, but Biolog identification showed it was P. spinosa. 16S rDNA determination and analysis was used for further identification, which showed that the 16S rDNA sequence of X3 shared 93.7% homologies with published sequence of P. aeruginosa from GenBank, and both sequences constituted a branch in Phylogenetic tree. Based on these results, it is considered that the strain X3 belongs to one strain of P. aeruginosa.