PHYLOGENETIC-RELATIONSHIPS AND HOST-RANGE OF RHIZOBIUM SPP - THAT NODULATE PHASEOLUS-VULGARIS L

We determined the nucleotide sequences of 16S rRNA gene segments from five Rhizobium strains that have been isolated from tropical legume sp ecies. All share the capacity to nodulate Phaseolus vulgaris L., the c ommon bean. Phylogenetic analysis confirmed that these strains are of two different chromosomal lineages. We defined the host ranges of two strains of Rhizobium etli and three strains of R. tropici, comparing t hem with those of the two most divergently related new strains. Twenty two of the 43 tested legume species were nodulated by three or more o f these strains. All seven strains have broad host ranges that include woody species such as Albizia lebbeck, Gliricidia maculata, and Leuca ena leucocephala.