【摘要】 通过菌株生态定殖以及抗病物质分析,初步探究解淀粉芽胞杆菌(Bacillus amyloliquefaciens)YH-22抗青枯病(茄科雷尔氏菌所致)的机制。采用利福平抗性诱导,获得抗400μg/mL的抗性菌株以利于定殖研究。盆栽试验结果表明,YH-22先在烟草根际土壤定殖,然后依次进入根部、茎部。对YH-22菌株发酵上清液进行理化性质分析,发现抗茄科雷尔氏菌活性物质不溶于氯仿和乙酸乙酯,能溶于甲醇,具有一定的耐热性,能耐受胃蛋白酶和紫外线,具有排油和使液滴坍塌的特性。综上所述,生防菌YH-22在烟草根际土壤、根、茎均具有一定的定殖能力,其抗菌物质可能为蛋白质和脂肽的混合物。更多还原

【Abstract】 Through the analysis of ecological colonization and antimicrobial substances of Bacillus amyloliquefaciens YH-22, the resistance mechanism of YH-22 against bacterial wilt which was caused by Ralstonia solanacearum was preliminarily investigated. The tolerance dosage of YH-22 resistance strain against rifampicin reached 400 μg/mL by resistance induction with rifampicin. The results of pot experiments showed that YH-22 resistance strain firstly colonized on the rhizosphere soil. Then, it intruded into the root and stem successively. The antimicrobial substances in broth could be dissolved by methanol, but not by chloroform and ethyl acetate. They could maintain high stability under the conditions of heat treatment, protease hydrolysis and Ultraviolet. Moreover, they had the character of oil displacement and droplet collapse. In conclusion, strain YH-22 has colonization ability in rhizosphere soil as well as tobacco tissue. The antibacterial components of strain YH-22 may consist of proteins and lipopeptides.更多还原