effect of sodium nitroprusside on growth, yield and yield components of bean (phaseolus vulgaris l.) under water deficit stress

in order to investigate the effect of sodium nitroprusside (snp) application on yield and yield components of kidney bean under water deficit stress, a field experiment was conducted in split-factorial based on randomized complete block design with three replications in hamedan, in 2012. water deficit stress at four levels including vegetative stress, reproductive stress vegetative+reproductive stress and without stress as main plot and cultivars (akhtar and derakhshan) and snp foliar at three concentrations (0, 150 and 300 µm) as sub plot were used. results showed that interaction between water deficit and foliar application had significant effect on characteristics such as subshrub number per plant, pod number per plant, seed number per pod, seed weight, seed yield and biological yield. vegetative+reproductive stress reduced seed yield in akhtar and derakhshan cultivars about 34 and 35.5 percent. reproductive stress reduced seed yield and it's components about 6 and 6.5 percent in akhtar and derakhshan cultivars more than vegetative stress. snp application (300 µm) enhanced seed yield in akhtar and derakhshan cultivars about 17 and 16 percent under reproductive stress. 300 µm concentration of snp had most influence on amelioration of water stress effect on yield and yield components of both cultivars. so, it’s recommended snp foliar application (300 µm) for bean under water deficit stress.