Evaluation of Dry Bean Cultivars in Turkey for Resistance against Common Bacterial Blight Disease

Background: Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) has been recorded as one of the most important seed-borne destructive diseases of beans, affecting its production worldwide. Since chemical compounds cause serious damage to natural ecosystems and in some instances fail in controlling CBB, the use of genetically resistant cultivar is the most economically efficient and environmentally friendly measure in the control of CBB disease. The objective of this study was to assess the resistance reactions of widely grown and popular common bean cultivars against Xap under controlled conditions. Methods: In this study, 16 dry bean cultivars comprising eight widely grown dry bean varieties, six improved and promising genotypes and two known CBB susceptible varieties, were evaluated for their reaction to the CBB in a completely randomized design with three replications. The reaction of the bean cultivars to Xap was assessed using disease incidence, disease severity, per cent severity index, the area under disease progress curve (AUDPC) and incubation period. Result: Data analysis indicated that there were highly significant differences (p£0.01) among common bean cultivars for CBB disease incidence, disease severity, per cent severity index and AUDPC among cultivars. The cultivated varieties Noyanbey and Özmen were identified as resistant cultivars. In addition, SAP6 and BAC6 resistance genes were found in these two cultivars. As a consequence, it was thought that these cultivars could be a potential source of disease resistance for CBB in breeding programs and sustainable, eco-friendly and good agricultural practices.