Effects of Deficit Irrigation on Yield and Yield Components and Determination of Water Productivity of Zea Maize in Islamabad-Gharb Area

Some experiments were performed around the Agricultural and Natural Resources Research Station of Islamabad-Gharb city in order to determine the reaction of corn crop to deficit irrigation strategy and its effects on yield, yield components and water productivity (WP) under furrow irrigation. The research used randomized complete block design (as a composite analysis in two years (2015 and 2016)). The treatments included irrigation with 100%, 75%, 50% and 25% water requirement with three replications. The SC704 Variety was used for planting corn. To compare the treatments, the 7 parameters of the performance components were considered, using analysis of variance (ANOVA). The results showed that the weight of corns in the first treatment was significantly superior to other treatments. Nevertheless, there was no significant difference in total weight of ears, ears length, seeds number per row, number of ear rows, wood weight and the weight of 1000 corns between treatments of 100% and 75% water requirement. However, in all measured attributes, there were significant differences between the other two treatments and the first and second treatments. Regarding water productivity in terms of total weight and grain weight of ears, the 75% treatment was superior to other treatments and had significant differences with the other treatments. In the treatment with 75% water requirement, WP was 0.8 kg/m3 based on the total weight of the grains, and based on the seed weight, it was 0.62 kg/m3, which were, respectively, 17% and 13% higher than the full irrigation treatment. The results showed that the highest water productivity was observed with about 30% deficit irrigation. It is to be noted that deficit irrigation may increase salinity of the root zone.