Identifying Tomato Wilt disease and Controlling It Using Antagonist Bacteria in East Azerbaijan Province

Bacterial wilt caused by Ralstonia solanacearum is one of the most destructive diseases which negatively affect the tomato production worldwide. Considering the importance of the disease, using biological control agents could be effective approaches in reducing the damage of the pathogen. Tomato samples of suspected bacterial wilt disease were gathered from different regions of East Azarbayjan. Phenotypic identification of the strains was performed using recommended biochemical and physiological tests. In genotypic assessment, strains could amplify a 282 and 148 bp fragment with the 759/760 and PS96I/ PS96H primers, respectively. Based on phenotypic and genotypic properties, the strains that cause wilt of tomato were identified as R. solanacearum biovar 2  For biological control of the disease, 15 bacterial strains were collected from rhizosphere of tomato using soil serial dilution method. Antagonistic effect of the strains was evaluated based on their growth inhibitory of pathogen. According to the results three bacterial strains showed antagonistic activity towards R. solanacearum. Based on phenotypic and genotypic characteristics the antagonist strains Ka1, Ka2 and Ka3 were identified asBacillus subtilis and Psudomonas fluorescens, respectively.