Diversity and Physiological Characteristics of Ralstonia solanacearum from Potato Fields in Hamedan Province

Bacterial wilt disease caused by Ralstonia solanacearum is an important disease on potato in Hamedan province. During spring and summer 2011 infected plants were collected from potato fields to investigate the genetic diversity among R. solanacearum strains. A total of 52 strains were isolated on NA medium containing triphenyl tetrazolium chloride (TTC) from tubers and stems and their phenotypic characteristics revealed that they were belong to biovar 2A. PCR using ps96h and ps96i primers produced 148 bp bands in tested and standard strains. Genetic diversity of 26 selected strains were analyzed by PCR fingerprinting using, ERIC and BOX primers. The length of produced fragments ranged from 200bp to 1200bp in BOX primer and 200bp to 1500bp in rep primer. Tested bacterial strains were grouped based on the obtained molecular DATA from PCR using UPGMA method and Jaccard`s coefficient. Results showed five distinguished clusters. R. solanacearum strains were genetically divers although no direct connection was observed between geographic locations and PCR groups. The results of this study indicated that rep-PCR technique with two ERIC and BOX primers is capable to show genetic polymorphism among different populations of R. solanacearum.