Clustering of the Dominant Broad-Bean Root Nodulating Bacteria Based on 16S rDNA and Their Phenotypic Pattern

Broad bean is one the most important legume plants in the world. Characterization and clustering of the root nodulating bacteria on this plant is a noteworthy issue. In spring 2011 root samples were collected randomly from broad bean fields in Lorestan province. A total of 65 bacterial strains were isolated which among them 58 strains could nodulated broad bean roots under green house condition. Phenotypic characteristics of these strains were determined based on the standard bacteriological methods. Results showed that they were belongs to two species includingRhizobium leguminosarum and R. etli. Total DNA from some representatives strains were isolated and they were subjected to PCR using specific primers for amplification of 16S rRNA encoding gene. Sequence analysis of the amplified PCR band from a broad-bean root nodulating representative strain by NCBI blast software revealed that the tested strains has high sequence similarity to R. leguminosarum bv. viciae strain BIHB. Clustering of the isolated strains showed a single separated cluster for representative strain with high similarity among the diverse R. leguminosarum bv. viciae.