解淀粉芽胞杆菌的GFP标记及定殖能力

采用改良的海藻糖电转化法获得GFP标记菌株X5-GFP、BQA2-GFP,显微镜观察标记菌株在土壤和水培中的番茄根际的定殖情况。结果表明:标记菌株单独或与青枯菌先后加入进行处理,番茄根际标记菌株的种群数量变化趋势都是一致的。在土壤番茄根际中,X5-GFP单独处理后当天的菌量为1.05×106CFU/g,随之菌量逐渐下降;处理30 d后,为1.50×10~3CFU/g;而BQA2-GFP单独处理后当天菌量为1.68×106 CFU/g,随之菌量也逐渐下降;处理30 d后,为2.50×10~3CFU/g;在水培番茄根际中,X5-GFP单独处理后当天的菌量为2.70×10~5CFU/g,随之菌量逐渐下降;处理30 d后,为1.00×10~3 CFU/g;而BQA2-GFP单独处理后当天菌量为3.60×10~5CFU/g,随之菌量同样逐渐下降;处理30 d后,为1.50×10~3 CFU/g。这表明解淀粉芽胞杆菌X5、BQA2均在番茄根际有较强的定殖能力。

Green Fluorescent Protein Labeling and Colonization Ability of Bacillus amyloliquefaciens

In this study,green fluorescent protein tagged strains X5 and BQA2 were obtained by improvement in electroporation transformation efficiency of gene for Bacillus amyloliquefaciens with trehalose.X5-GFP and BQA2-GFP colonization in the rhizosphere of tomato were observed by microscope.The experimental results indicated that changing tendency of population quantity in marking strains of tomato rhizosphere was consistent after dealing with individual marking strains or adding Ralstonia solanacearum successively.In the soil,the population of X5-GFP on the roots of tomato reached 1.05×106 CFU/g after inoculating X5-GFP alone,and then decreased 30 days later,eventually remained at 1.50×103 CFU/g.The population of BQA2-GFP on the roots of tomato reached 1.68× 106 CFU/g after inoculating BQA2-GFP alone,and then decreased 30 days later,eventually remained at 2.50× 103 CFU/g.In Hydroponics,the population of X5-GFP on the roots of tomato reached 2.70×105 CFU/g after inoculating X5-GFP alone,and then decreased 30 days later,eventually remained at 1.00×103 CFU/g.The population of BQA2-GFP on the roots of tomato reached 3.60×105 CFU/g after inoculating BQA2-GFP alone,and then decreased 30 days later,eventually remained at 1.50×103 CFU/g.The results showed that B.amyloliquefaciens X5 and B.amyloliquefaciens BQA2 displayed good colonization ability in the rhizosphere of tomato.