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期 刊 ：植物保护学报 2011年

关键词：铁载体产生菌；鉴定；诱变选育；16S rDNA；

Keywords:siderophore-producing bacterium, characterization, mutation breeding, 16S rDNA,

摘 要 ：从桃树根际土壤中分离到81株细菌,通过铬天青(chrome azural S , CAS)检测法筛选出一株产铁载体能力较强的细菌菌株MX-26,经形态、生理生化特征鉴定及16S rDNA序列分析,确定MX-26为克雷伯氏菌属产酸克雷伯氏菌Klebsiella oxytoca。以MX-26为出发菌株,对其进行紫外诱变、紫外和氯化锂复合诱变及硫酸二乙酯(DES)诱变,得到菌株的最佳诱变组合:紫外线照射时间为180 s,氯化锂终浓度为1.2%,硫酸二乙酯诱变时间为40 min。诱变获得菌株MX26-18,其产铁载体能力较出发菌株提高了32.9%,且遗传性能较稳定。

Abstract:Using the chrome azural S (CAS) reagents assay, a siderophore-producing bacterium MX-26 was screened out from 81 bacteria, which were isolated from the peach rhizosphere soil. According to morphological, biochemical characteristics and 16S rDNA sequence analysis, strain MX-26 belong to Klebsiella oxytoca. As an original strain, MX-26 was mutated by UV-ray, complex mutagenesis of UV-ray and lithium chloride (LiCl), diethyl sulphate (DES), the optimum mutagenesis conditions were determined: mutated by UV-ray was tested to be 180 seconds, the concentration of lithium chloride should be 1.2% and mutated by the diethyl sulphate was tested to be 40 minutes. The mutants of strain MX26-18 was obtained. Compared with MX-26, the siderophore production from MX26-18 was increased by 32.9%. And the subculture experiments indicated that the hereditary characteristic of MX26-18 was stable.

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