中文摘要：

对分离自西北部分地区鸡眼草（Kummerowia striata）的53株根瘤菌,进行唯一碳源和氮源利用、抗生素、染料和苯酚抗性、耐盐性等98项生理生化性状测定,并结合16SrDNA PCR-RFLP分析,对供试菌株进行了遗传多样性研究。结果表明,不同地理来源,甚至来源于同一地区的不同菌株在碳、氮源利用、耐盐性、对苯酚抗性程度等方面存在着一定差异,12.5%的菌株能耐受300μg/mL氯霉素,58.9%的菌株能耐受2%NaCl,38%的菌株能耐受700mg/L苯酚。通过16SrDNA PCR-RFLP分析,53株供试菌株分别属于慢生根瘤菌属（Bradyrhizobium）、中慢生根瘤菌属（Mesorhizobium）、根瘤菌属（Rhizobium）、中华根瘤菌属（Sinorhizobium）和土壤杆菌属（Agrobacterium）,说明分离自鸡眼草的根瘤菌在种及属的水平上具有非常丰富的遗传多样性。

英文摘要：

Fifty three rhizobial strains isolated from root nodules of Kummerowia striata in part of northwest China were studied by a series of analysis on C,N nutrient utilization,resistance to antibiotics,colorant and hydroxybenzene,endurance to salt and alkali.At the same time,16S rDNA PCR-RFLP and phylogeny analysis were used to study the genetic diversity of these strains.The results showed that there were great diversity among these strains,12.5% of strains could resist 300 μg/mL chloramphenicol,58.9%of strains could resist 2% NaCl,38%of strains could resist 700 mg/L hydroxybenzene.The analysis of 16S rDNA PCR-RFLP revealed that these tested rhizobial strains belonged to Bradyrhizobium,Mesorhizobium,Rhizobium,Sinorhizobium and Agrobacterium,respectively.Apparently,the great genetic diversity at the level of species and genus exists among Kummerowia striata rhizobia in northwest China.