Drought stress effects on two common bean cultivars with contrasting growth habits

In most rainfed production areas where wheat fallow is common, crop yield could be improved by changing to more diverse crop rotations. It seems necessary to identify crop cultivars suitable for such diversification. This study was aimed at determining the responses of two common bean cultivars with different growth habits (Sayyad as an indeterminate and D81083 as a determinate cultivar) to drought stress. The study was conducted in a greenhouse during the 2008 growing season. A factorial experiment in a randomized complete block design with four replications and four water levels [100, 75, 50 and 25% of field capacity (FC) by weight] was used. The results showed that plant height, number of leaves, leaf area, number of pods, pod dry matter (DM) and total plant DM weights of both cultivars were significantly reduced under drought stress. Furthermore, at 50 and 25% FC, all plant pods of both cultivars were aborted. The common bean cultivar with a determinate growth habit appeared to have potential as a dryland rotation crop for farming in arid regions. Further field research might shed more light on the sensitivity of bean cultivars to drought stress with the aim of crop diversification for dryland areas, where adequate moisture supply is a limiting factor for crop production.