USE OF REPETITIVE SEQUENCES AND THE POLYMERASE CHAIN-REACTION TO FINGERPRINT THE GENOMIC DNA OF RHIZOBIUM-GALEGAE STRAINS AND TO IDENTIFY THE DNA OBTAINED BY SONICATING THE LIQUID CULTURES AND ROOT-NODULES

Repetitive sequences (repetitive extragenic palindromic [REP] and enterobacterial repetitive intergenic consensus [ERIC]) together with the polymerase chain reaction (PCR) were used to fingerprint pure DNA extracted from seven different Rhizobium galegae strains. The resulting PCR patterns were found to be highly specific for each strain and the REP PCR grouped the strains according to the host plant, Galega orientalis and Galega officinalis. The dendrogram generated from the REP PCR patterns correlated with the dendrogram derived from previous restriction fragment length polymorphism (RFLP) analysis. DNA was also extracted by sonication from R. galegae liquid cultures and root nodules and used in REP and ERIC PCR. The results obtained indicate that this technique coupled with the sonication of nodules can be a useful tool for genotypic characterization and identification of rhizobia as well as for diversity studies.