Evaluation of morphological aspects of common bean (Phaseolus vulgaris L.) genotypes for post-flowering drought resistance in Rift Valley of Ethiopia

The development of bean varieties adapted to drought situations is a key strategy to minimize crop failure and improve food security. In this study, 25 genotypes of common beans (Phaseolus vulgaris L.) were grown under post flowering drought stress and non-stress conditions to evaluate their performance at Melkassa Agricultural Research Center during the off-season months (from December to May) in 2011/2012. The treatments were laid out on a triple lattice design with three replications. A number of plant attributes were measured at mid-pod fill and harvesting stages. Under drought stress, the highest seed yield (125.3 gm -2 ) was recorded for a Dimtu variety, while the lowest (72.5 gm -2 ) for SB15945-17. Therefore, Dimtu was the most drought tolerant genotype under drought stress. On the contrary, SB-15945-17 had the lowest seed yield under drought stress and drought-induced seed yield reduction of 50.8%. Seed yield showed significant and positive correlation with number of pods per plant (r =0. 39), number of seeds per pod (r =0. 32) and hundred seed weight (r =0. 41) under drought stress. The study demonstrated the existence of genetic variability among the common bean genotypes when subjected to post-flowering drought stress and such variability could be utilized in the development of common bean genotypes suitable for drought prone-areas.