Response of different beans against common bacterial blight disease caused by Xanthomonas axonopodis PV. phaseoli

Abstract

Common bacterial blight (CBB) in beans, caused by the bacterium Xanthomonas axonopodis pv. phaseoli (Xap), is an economically important disease worldwide which reduces crop yields and seed quality. Since there is no satisfactory chemical control for the disease, the use of resistant cultivars is an important management strategy. Sources of immunity are not yet recognized, but tolerance has been reported in several genetic stocks. The main objective of this study was to determine resistance to CBB on twenty-two local and foreign beans grown in Serbia. Two inoculation methods with Xap (spraying and multiple needles) as well as naturally infected plants in field conditions were taken for evaluation. The experiments were conducted in randomized complete blocks with three replications. Reaction to Xap was assessed as a diseased leaf area and the disease severity index was calculated. The analysis of variance (ANOVA) for disease ratings of leaf reactions indicated significant interactions between cultivars and lines. Results indicate that none of evaluated beans was immune and was found to be resistant to CBB. HR 45, Oreol and XAN 159, -208, -273 were weakly susceptible; Biser, Dobrudzanski rani, KB 100, -101, Medijana, Naya Nayahit, Panonski gradistanac, Panonski tetovac, and Sremac were susceptible while Balkan, Belko, Dobrudzanski rani 7, Dvadesetica, Galeb, Maksa, Slavonski zutozeleni, and Zlatko were highly susceptible cultivars and lines. The five weakly susceptible can be identified and recommend as possible sources of tolerance in plant breeding program.