Effect of Different Deficit-Irrigation Methods on Yield and Water Use Efficiency of Wheat (Parsi Cultivar)

To study the effect of different deficit-irrigation methods on yield and water use efficiency of wheat under different water applications a field experiment was carried out in split plot arrangement using randomized complete block design with four replications at the Research Farm of Islamic Azad University, Karaj branch, Iran in 2014-2015 growing year. Deficit irrigation with three levels were I100: use of 100% wheat water requirement, I75: use of 75% wheat water requirement and I50: use of 50% wheat water requirement, which were assigned to the main plots and irrigation methods with three levels, consisting of M1: conventional furrow irrigation, M2: fixed alternate-furrow irrigation and M3: periodic alternate-furrow irrigation which were assigned to the sub plots. The results showed that by using 100% wheat water requirement grain yield in the fixed and periodic alternate-furrow irrigation methods decreased by 21.8 and 23.7 percents as compared to conventional furrow irrigation method, respectively. The highest water use efficiency for grain yield (1.63 kg.m-3) was obtained when 75% wheat water requirement and fixed and alternate-furrow irrigation methods and the lowest water use efficiency for grain yield (1.24 kg.m-3) was obtained when to 50% wheat water requirement, with conventional furrow irrigation method, was used. Also, the highest water use efficiency for biologic yield (4.38 kg.m-3) was obtained at 50% wheat water requirement, with fixed alternate-furrow irrigation method, that decreased 31.5 percent as compared to I100M1. According to the results of this study, the application of alternate furrow irrigation with 75% crop water requirement can be used to increase water use efficiency for wheat yield in the studied area.