PHYLOGENETIC GROUPING AND IDENTIFICATION OF RHIZOBIUM ISOLATES ON THEBASIS OF RANDOM AMPLIFIED POLYMORPHIC DNA PROFILES

Through the use of a single, random 15mer as a primer, between 1 and 1 2 DNA amplification products were obtained per strain from a selection of 84 Rhizobium and Bradyrhizobium isolates. A principal-coordinate a nalysis was used to analyse the resulting amplified DNA profiles and i t was possible to assign isolates to specific groupings. Within the sp ecies Rhizobium leguminosarum, the biovar phaseoli formed a distinct g roup from the other biovars of the species, viciae and trifolii, which grouped together. Isolates of Rhizobium meliloti and Bradyrhizobium s pecies formed their own clear, specific groups. Although it was possib le to identify individual isolates on the basis of differences in thei r amplified DNA profiles, there was evidence that some amplified segme nts were conserved among individuals at the biovar and species levels.