Effects of drought stress and potassium sulfate fertilizer on green bean yield

A split plot experiment based on complete block design with three replications was carried out to evaluate the effect of irrigation and potassium fertilizer on yield and yield components of green beans, in 2011 at Ahvaz. Two levels of irrigation (normal irrigation and drought) and four levels of potassium sulfate fertilizer (0, 25, 50 and 100 kg ha-1) were evaluated in this study. The results of analysis of variance indicated that there were significant effects of irrigation, potassium sulfate fertilizer and irrigation × potassium sulfate fertilizer interactions on all of the studied traits. The results of mean comparisons indicated in both conditions of irrigation, the high value of yield and yield components were obtained by use of 50 kg ha-1 potassium sulfate fertilizer. The results of trend analysis revealed that effect of potassium Sulfate fertilizer on dry grain yield and yield of green pods can be explained by the quadratic equation. The results of the correlation analysis indicated that there were positive and significant correlation between dry grain yield and plant height, number of grains per pod and number of pods per plant. In conclusion, the results indicated increasing that potassium sulfate fertilizer was partly prevented high reduction of grain yield in drought condition.