Interaction of Superabsorbent Polymer and Supplemental Irrigation Technique to Increase Yield and Irrigation Water use Efficiency in Rainfed Wheat Cultivation

This study was conducted to investigate the effect of supplemental irrigation and Stockosorb superabsorbent on yield, yield components and water use efficiency in irrigated wheat during 2015-2016 crop years in agricultural faculty of Tabriz University as factorial in randomized complete block design with three replications. Experimental treatments consisted of supplemental irrigation at three levels of without irrigation (I0), irrigation once in June (I1) and irrigation twice in May and June (I2), and the use of Stockosorb superabsorbent at three levels of 0, 50 and 100 kg.ha-1. (S0, S1 and S2). The results showed that supplemental irrigation was significant on all traits at the level of 1%, but no significant effect of superabsorbent was obtained on biological yield. Interactions in the number of grains per panicle, yield and water use efficiency were significant at the level of 1% and in thousand kernel weight and economical productivity at the level of 5%. The highest yield and water use efficiency was obtained from treatment S2I1, respectively, 4.35 ton.ha-1 and 1.20 kg.m-3. The highest yield and water use efficiency were increased respectively by the amount of 2.74 ton.ha-1 and 0.66 kg.m-3 compared to control. The results of the economic analysis showed that superabsorbent consumption without supplemental irrigation has no economic justification in dry land farming of wheat. Considering the economic analysis, treatment S0I1 with 134.8% increase in yield and 94.4% increase in water use efficiency has the best conditions compared to control. The highest irrigation water use efficiency (3.5 kg.m-3) was obtained from treatment S1I1.