Effect of Different Irrigation Regimes on Yield Water Use Efficiency and Harvest Index of Soybean Cultivars in Khorramabad

Document Type : Research Paper



Due to limited water resources, one of the strategies for optimum utilization of water resources in agriculture is deficit irrigation.To examine the effects of different irrigation regimes on soybean yield, water use efficiency, harvest index, oil and protein, a study was conducted on M7, M9, TMS cultivars in the Research Field of College of Agriculture, Khorramabad, Iran during the growing season of 2010-2011. The experiment was arranged in a randomized complete block design as split-plot with three replications. Irrigation regimes were the main plots and the subplots were three soybean cultivares. Irrigation treatments were conducted as follow; CI: applied 100% of water requirements during the whole season and RDI80, RDI70 and RDI50 applied 80%, 70% & 50% of water requirements, respectively. Based on the findings of this study, any increase in the irrigation water resulted in the increase of the total weight of dry matter (3-5.7 ton.ha-1) and seed yield (1.3-2.5 ton.ha-1) of different soybean cultivars. Increasing irrigation water had significant effect on the percentage of seed protein and oil. M9 cultivar had the most yield (2.1 ton.ha-1), total yield (4.7 ton.ha-1) and water use efficiency (0.56 kg.ha-1.mm) in the water stress condition and non water stress condition among the studies cultivars.