Evaluation of advanced common bean lines for resistance to common bacterial blight (CBB) based on factor analysis and cluster analysis

Common bacterial blight (CBB), caused by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major diseases in common bean fields leading to significant losses in yield and seed quality. Application of resistant varieties is the effective disease management. In this study, 15 bean genotypes with the Sadri cultivar as a check varaiety were cultivated in the field of Agricultural and Natural Resources Research Center of Markazi province during 2015 and 2016 which were inoculated with bacterial suspension (107 cell/ml) before flowering stage. The resistance of genotypes was assessed in the pre-physiological maturity stage. The results showed that CBB reduced yield average 33.2% in the studied lines. Also, yield components including number of pods per plant, number of seeds per pod and one hundred seed weight reduced 28.9%, 17% and 15.6% respectively.Finally, based on factor and cluster statistic analysis, five bean lines with the highest geometric mean productivity and steress tolerance index and the lowest stress susceptibility index were selected. VAX3 and Ks31118 genotypes were released as CBB resistant red bean varieties due to their marketability and suitable grain color. Also VAX1, VAX5 and VAX6 lines can be used as the parents in bean hybridization programs to release resistant varieties to this disease.