Effect of water stress on growth and yield of indeterminate dry-bean ( Phaseolus vulgaris) cultivars

Abstract

Bean seed yields in the Mexican Plateau are heavily dependent on natural rainfall. This research was conducted to determine the effects of a water shortage applied at two different phenological stages upon the growth and seed yield of three indeterminate dry-bean cultivars. The cultivars used were: Pinto Nacional 1 (PN1), Bayo Calera (BC), and Ojo de Cabra (OC). All growth and yield-related parameters were reduced by the water-stress treatments. In 1981 and 1982, the reduction in growth and seed yield was higher when the water stress was applied during the reproductive phase (WSRP) than during the vegetative stage (WSVP). In 1981 WSRP treatment decreased seed yield 42 and 50% for BC and OC, respectively, whereas WSVP treatment reduced yield 37 and 39%. In 1982 the WSRP treatment reduced seed yields by 34, 39, and 35% for PN1, BC and OC, respectively. Yield reductions in the water stress treatments were due to a decrease in leaf-area index. ( lai). Number of pods/plant was the yield component most adversely affected by the strese treatments. The use of visual score for general vigor and reduced leaf senescence, combined with an estimate of number of pods/plant at maturity, is suggested for the identification of promising stress-resistant genotypes.