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从甜椒根际土壤中分离到一株对辣椒疫霉(Phytophthora capsici)具有强拮抗作用的假单胞属(Pseudomonasspp.)菌株GP72,研究其拮抗性表明,对多种植物病原真菌均有很强的抑制作用。对该菌株进行形态特征、生理生化、Biolog GN、(G+C)mol%含量测定及16S rDNA序列分析,鉴定为绿针假单胞菌(Pseudomonas chlororaphis)。特征为单细胞,极生单个鞭毛,不能利用聚β-羟基丁酸盐,能够较强地利用Biolog系统95种碳源中的45种作为底物生长,较弱利用其中的6种底物,与绿针假单胞菌(Pseudomonas chlororaphis)的相似性达到98%,相似指数为0.72。用热解链方法测得基因组DNA的(G+C)mol%含量为65.1mol%。以16S rDNA序列为基础构建了包括13株邻近种属细菌在内的系统发育树,其中与模式致金色假单胞菌的同源性最近。
A Pseudomonas sp. Strain GP72 isolated from sweet pepper rhizosphere soils was isolated from Phytophthora capsici and its antagonistic activity was shown to be very versatile for many plant pathogenic fungi Strong inhibitory effect. The strain was identified as Pseudomonas chlororaphis by morphological, physiological and biochemical characteristics, Biolog GN, (G + C) mol% content determination and 16S rDNA sequence analysis. It is characterized by single flagella of single cell and polar body, can not utilize poly-β-hydroxybutyrate, can use 45 kinds of 95 kinds of carbon sources of Biolog system as substrate to grow stronger, use 6 kinds of substrates weakly, The similarity with Pseudomonas chlororaphis reached 98%, and the similarity index was 0.72. The (G + C) mol% content of the genomic DNA was 65.1 mol% as determined by the thermal melting method. Based on the 16S rDNA sequence, phylogenetic trees including 13 adjacent species of bacteria were constructed, of which the homology with the model Pseudomonas aeruginosa was the closest.