中文摘要：

利用钼蓝比色法、乙炔还原法和高效液相色谱法分别测定了分离自5种植物根际的19株细菌溶磷、固氮和分泌生长素特性;用平板对峙生长法测定了19株细菌对黄瓜枯萎病菌和小麦根腐病菌的抑制作用;结合菌株形态、生理生化反应,利用分子生物学方法鉴定了其中8株优良细菌。结果表明,菌株Bacillus subtilis LM4-3固氮酶活性较高[244.88nmol C2H4/（mL·h）];菌株B.subtilis LHS11-1溶磷能力较强（205.77mg/L）;菌株PGRS-3分泌IAA能力较好（40.78μg/mL）。5株菌株能够有效拮抗黄瓜枯萎病菌,其中B.subtilis FX2-1抑菌活性较强（活菌抑制率69.07%,发酵液抑制率51.73%）。7株菌株能够有效拮抗小麦根腐病菌,其中B.subtilis FX2-1抑菌活性较强（活菌抑制率78.17%）,B.subtilis LHS11-1发酵液抑制率高达81.52%。其他具有较好促生或拮抗上述两种病原真菌的菌株经鉴定,分别属于蜡样芽孢杆菌（B.cereus,菌株XX1）、短小芽孢杆菌（B.pumilus,菌株F1-4和LX22）、简单芽孢杆菌（B.simplex,菌株XX6）和荧光假单胞杆菌（Pseudomonas fluorescens,菌株XX5）。

英文摘要：

The capacity for dissolved phosphorus absorption,the nitrogenase activity and the secretion of auxin of 19 strains of plant growth promoting rhizobacteria （PGPR）acquired from five plant species were tested by molybdenum blue colorimetry,acetylene reduction assay and high performance liquid chromatography,respec-tively.All 19 strains were tested for ability to antagonize the fungi Fusarium oxysporum f.sp.cucumerinum and Bipolaris sorokiniana ,using the panel confrontation method.Strains with antagonistic ability were identi-fied at morphological,physiological biochemical,and molecular levels.It was found that Bacillus subtilis strain LM4-3 had stronger nitrogenase activity than other tested strains and reached 244.88 nmol C2 H4/（mL·h）,while B .subtilis strain LHS11-1 had the highest dissolved phosphorus absorption capacity （205.77mg/L）,and the strain PGRS-3 had the greatest secretion of auxin,reaching 40.78 μg/mL in the culture medi-um.Five bacterial strains were found to have antagonistic activity against F .oxysporum f.sp.cucumerinum, with B .subtilis strain FX2-1 providing up to 69.07% suppression.and 51.73% of its fermentation solution. Seven bacterial strains could efficiently antagonize B .sorokiniana,with B .subtilis strain FX2-1 achieving 78.17%,the fermentation solution of B .subtilis LHS11-1 rinsed up to 81.52%.Other bacterial species found to have plant growth promoting or to be antagonistic towards the above two pathogenic fungal species included Bacillus cereus ,Bacillus pumilus ,Bacillus simplex and Pseudomonas fluorescens .