Abstract：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.
