Virulence Function of Pectobacterium atrosepticum Secretion System Mutants on Evaluation of Some Solanum tuberosum Resistance Genes

Background: P. atrosepticum is a commercially important pathogen. It causes blackleg in the field and soft rot of tubers after the harvest. This effect is due to secretion of depolymerases and other virulence factors by several mechanisms including T3SS Objectives: The effect of bacterial T3SS on Solanum tuberosum (S. tuberosum) varieties and its relationship with S. tuberosum resistance gene expression were studied. Materials and Methods: A P. atrosepticum HrpW gene was cloned, sequenced and constructed a phylogenic tree with some phytopathogen. The virulence properties of P. atrosepticum strains were investigated and then S. tuberosum varieties were tested for their sensitivity against P. atrosepticum. PR-5 and HIN genes copy-number for infiltrated S. tuberosum tubers were assessed. Results: The results show that infiltrated tubers of P. atrosepticum T3SS mutants were significantly more macerated than the wild type ones. Conclusions: PR-5 and HIN expression amounts were depended on bacterial T3SS function.