Y-21是从山东省淄博市蔬菜温室中分离到的一株细菌,通过室内平板对峙试验,对番茄灰霉病菌具有较强的拮抗性。本研究通过形态观察、生理生化反应和分子生物学方法对这株细菌进行系统鉴定。显微镜观察菌株形态为杆状;有芽孢;革兰氏染色呈阳性。采用经典的基因组提取方法提取基因组DNA,以其为模板,利用引物63F、1494R扩增16S rRNA基因,回收16SrRNA基因的PCR产物并与T载体连接,通过热激法将重组质粒转入大肠杆菌感受态细胞,利用蓝白斑筛选,挑出白斑,提取质粒,通过蓝白斑质粒的电泳图比对和质粒的PCR检测确定阳性克隆,将阳性克隆菌株送样测序。将测序结果输入BLAST进行比对,发现Y-21属于假单胞菌属,然后对其构建系统发育树。 Y-21 is a strain of bacteria isolated from vegetable greenhouse in Zibo City, Shandong Province. It has strong antagonistic activity against Botrytis cinerea by indoor plate confrontation test. In this study, the bacteria were systematically identified by morphological observation, physiological and biochemical reactions and molecular biology methods. Microscopic observation of the rod-shaped strains; spores; Gram stain was positive. The genomic DNA was extracted by classical genomic extraction and used as a template to amplify 16S rRNA gene with primers 63F and 1494R. The PCR product of 16S rRNA gene was recovered and ligated with T vector. The recombinant plasmids were transformed into E. coli via heat shock State cells were screened by blue and white stains, white spots were picked out, and plasmids were extracted. Positive clones were confirmed by electrophoresis map of blue-white plaques and PCR detection of plasmids. Positive clones were sent for sequencing. The sequencing results were entered into BLAST for comparison, and it was found that Y-21 belonged to Pseudomonas, and then phylogenetic tree was constructed.