一株分离自葛藤根际高效溶磷细菌特性研究及菌株鉴定

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7 d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。

Characteristics and identification of a dissolving phosphate bacteria strain isolated from rhizosphere of Pueraria lobata

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[Gram 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.