一株分离自葛藤根际高效溶磷细菌特性研究及菌株鉴定

摘要

对分离自葛藤(Pueraria lobata L.)根际的一株高效溶磷细菌GTR15进行促生特性、主要生理生化指标测定和16S rDNA序列分析.结果表明,菌株GTR15的HD/CD值(溶磷圈直径HD,菌落直径CD)为2.22,28℃液体振荡培养7d后对磷酸钙的溶解量为138.72 mg·L-1,分泌IAA(3-吲哚乙酸)及有机酸量分别为14.44 mg·L-1、46.00 mmol·L-1.菌株革兰氏染色为阴性,细胞短杆状；淀粉水解、吲哚、V-P(二乙酰试验)、苯丙氨酸脱氨酶、明胶液化及M-R(甲基红)试验呈阴性；柠檬酸盐、过氧化氢酶、硫化氢及硝酸盐还原等试验呈阳性,结合菌株16S rDNA序列分析结果,初步鉴定为肠杆菌(Enterobacter sp.).该菌株在研制高效微生物磷肥接种剂方面可能具有较大潜力.%Phosphate-dissolving bacteria GTR15 was isolated from the rhizosphere of Pueraria lobata L. The characteristics, including phosphate solubilizing, produing IAA (indole-3-acetic acid) and organic acid and physiological characteristics and 16S rDNA sequence analysis of bacteria were determined. The results showed that the HD/CD value of GTR15 strain was 2. 22, when it was inoculated into PKO liquid culture, the release of maximal available soluble phosphorus reached to 138. 72 mg· L-1 after 7 days incubation at 28%. It had the maximal capacity of producing IAA (14.44 mg· L-1) and organic acid (46. 00 mmol· L-1). Strain GTR15 was identified as Enterobacter sp. , based on its physiological characteristics [Cram stain negative, short rod-shaped cells; The tests which including starch hydrolysis, indole, V-P (Diacetate), phenylalanine deaminase, gelatin liquefaction and M-R (Methyl red) were negative, and the tests which including citrate, catalase, hydrogen sulfide and nitrate reduction were positive. ] and 16S rDNA sequence analysis. The strain has the great potential for developing the efficient microbial phosphate inoculant.