Genetic diversity in Thai strains of Erwinia carotovora subsp. Carotovora based on ERIC profiles and RFLP of a pel gene

Molecular fingerprinting techniques of enterobacterial repetitive intergenic consensus (ERIC) and restriction fragment length polymorphism (RFLP) of a pel gene were applied to determine genetic diversity in Thai strains of Erwinia carotavora subsp. carotovora. ERIC fingerprinting revealed a greater genotypic diversity with 10 PCR groups in 22 Thai strains. When PCR for the pel gene was carried out using the four subspecies atroseptica, carotovora, betavasculorum and wasabiae, no PCR products were obtained in the case of betavas-culorum. RFLP analysis with Sau3A was undertaken for the amplified fragments. Digestion patterns of 22 Thai strains were divided into two groups. ERIC group 1 and RFLP group 2 were composed of biovar D that were isolated from chinease cabbage, coriander and sweet pepper. The genetic diversity of E. carotovora subsp. carotovora appears to be related to their host plants and biovars in considering ERIC and RFLP data. These results indicate that ERIC and RFLP analyses will be useful as benchmarks for genetic characterization of E. carotovora at subspecies and infraspecific level.