The diversity and phylogeny of 30 rhizobia isolated from nodules of faba bean plants grown on 5 geographic regions located in the East Azerbaijan province of Iran were examined using rep-PCR fingerprinting, sequence analysis of 16S rRNA accompanied with nodC genes. Based on cluster analysis of rep-PCR fingerprints, faba bean rhizobia isolates were differentiated into five clusters (A to E) at 80% similarity level. The cophenetic correlation coefficient for the dendrogram obtained from the combined dataset of BOX and ERIC primers was 0.942. The percentage of polymorphic loci was 59.2% using the BOX-PCR primer and 67.3% using the ERIC-PCR primers. The data obtained by rep-PCR fingerprinting showed high apparent correlation between genetic diversity and geographical origin of the isolates. The phylogenetic analysis based on 16S rRNA and nodC sequences showed that representative isolates were closely related to R. leguminosarum bv. viciae and R. fabae. To the best of our knowledge, this is first report of isolation and characterization of R. fabae from Iran.
