中文摘要：

采用钼蓝比色法（molybdenum blue colorimetry,MBC）、乙炔还原法（acetylene reduction assay,ARA）及高效液相色谱法（high performance liquid chromatography,HPLC）测定了分离自无脉苔草根际的6株根际促生菌溶磷、固氮及分泌激素的特性,并利用16SrDNA序列分析技术对筛选出的2株优良促生菌进行鉴定。结果表明,6株促生菌的溶磷量在298.17-554.67mg/L之间,其中菌株TPRS3的溶磷能力最强（554.67mg/L）;6株促生菌中有4株具有固氮能力,固氮酶活性在170.19-456.87nmol C2H4/（mL·h）之间,菌株TPRS19的固氮能力最强,固氮酶活性为456.87nmol C2H4/（mL·h）,菌株TRPS3和TPRS12无固氮能力;6株促生菌均具有分泌植物激素的能力,其中3-吲哚乙酸（IAA）分泌量在8.20-86.36mg/L范围内,赤霉素（GA3）在26.36-135.90mg/L范围内,反-玉米素（t-Z）在9.55-141.68mg/L范围内,菌株TPRS19分泌IAA的能力最强,为86.36mg/L,菌株TPRS5分泌GA3的能力最强,为135.90mg/L,菌株TPRS2分泌t-Z的能力最强,为141.68mg/L,菌株TPRS3、TPRS5、TPRS12和TPRS19兼具分泌3种激素能力。经鉴定,菌株TPRS5为枯草芽孢杆菌（Bacillus subtilis）,菌株TPRS19为阴沟肠杆菌（Enterobacter cloacae）,这2株菌有望作为研制微生物肥料的优良菌株。

英文摘要：

Six plant growth-promoting rhizobacteria were isolated from Carex enervis.We analyzed the six strains to evaluate their phosphate solubilization（by molybdenum blue colorimetry）,nitrogen fixation（by the acetylene reduction assay）,and hormone secretion（by high performance liquid chromatography）.The two strains with the strongest P solubilization and N fixation abilities were identified by analyses of their 16 SrDNA sequences.The results showed that the phosphate solubilization capacity of the six strains ranged from 298.17 to 554.67mg/L（in strain TPRS3）.Four strains were able to fix nitrogen,with nitrogenase activity ranging from 170.19 to 456.87 nmol C2H4/（mL·h）（in strain TPRS19）,while strains TPRS3 and TPRS12lacked nitrogenase activity.All six strains secreted hormones（indole acetic acid（IAA）,ranging from 8.20 to 86.36mg/L;gibberellin（GA3）ranging from 26.36 to 135.90mg/L;and trans-zeatin（t-Z）,ranging from 9.55to141.68mg/L）.Strain TPRS19 secreted the largest amount of IAA（86.36mg/L）,strain TPRS5 secreted the largest amount of GA3（135.90mg/L）,and TPRS2 secreted the largest amount of t-Z（141.68mg/L）.Strains TPRS3,TPRS5,TPRS12,and TPRS19 could secrete all three hormones simultaneously.Strain TPRS5 was identified as Bacillus subtilis and TPRS19 was identified as Enterobacter cloacae.These strains have the potential for use as microbial fertilizers.