Investigating the Efficiency of BOX-PCR & ERIC-PCR Molecular Markers in Evaluation of the Genetic Diversity of Pectobacterium carotovorum subsp. carotovorum Strains in Different Hosts in East Azarbaijan

Background and Aim: Soft-rot is one the major diseases in many plant crops especially in tuber products and vegetables. Plant pathogenic bacteria is the main causative agents for soft-rot diseases. Various bacterial species have been reported as causal agent(s) for this disease, but Pectobacterium species are known as the major one with the globally widespread. The aim of this study was to investigate the efficiency of BOX and ERIC-PCR molecular markers in evaluation of genetic diversity of Pectobacterium carotovorum strains in different hosts.Methods: In this study, during the ۲۰۱۷ and ۲۰۱۸, about ۲۰۰ suspected samples for bacterial soft rot disease were collected from different hosts including carrot, potato, lettuce, cabbage, squash, tomatoes, onions, and green pepper from different regions of East Azarbaijan province. After bacteria isolation from samples, the initial identification and pathogenicity assays were performed then the positive isolates were selected for molecular studies. The ۱۶s rDNA universal primer was used for molecular identification.Results: The data obtained from rDNA sequencing showed that Pectobcterium carotovorum subsp. carotovorum is the main causal agent for soft rot diseases in the vegetables. The results of molecular studies were consistent with pathogenicity tests. Genetic variation among isolates was determined by BOX-PCR and ERIC-PCR markers.Conclusion: The results showed a high variability among collected bacterial strains and the strains were classified into different groups. There was no significant correlation between genetical groups and isolated hosts moreover genetic variation was mostly related to sampling site. Significant correlation was observed between genetic clusters of both markers and geographic coordinates of collected bacterial isolates.

Keywords:

soft rot , ۱۶s rDNA , BOX-PCR , ERIC-PCR