Interaction of Irrigation Regimes and Nitrogen Sources on Grain Yield and Water Use Efficiency of Wheat

Nowadays increase of population and need for food and limitation of water resources have caused that the worth of this vital liquid to be cleared up more than ever. A field experiment was conducted at Tabriz plain during 1997-2000 to determination the water requirement of wheat and interaction between applied water and sources of N fertilizer on water use efficiency (WUE). The experiment was carried out in factorial randomized complete block design with 4 irrigation levels (I1 to I4) based on Irrigation Depth per Cumulative Pan Evaporation (ID: CPE) ratios of 0.4, 0.6, 0.8 and 1.0 in combination with 3 sources of N (N1 to N3) comprising ammonium sulfate, urea and ammonium nitrate and with 4 replications. Results indicated that there was significant difference between I1 and other treatments on both biomass and grain yield, but there was no difference between I2, I3 and I4. WUE was different between treatments -3 -3 significantly. Treatment I1 producing 1.89 kgmand treatment I4 with 1.09 kgmhad maximum and minimum WUE respectively. Mean consumed water in 3 years (irrigation plus rainfall) for I1 to I4 was calculated to be 4556, 5776, 6685 and 7713 m3ha-1 respectively. There were no significant differences between treatments in 1000 kernel weight, harvest index (HI) and protein content of seeds. Sources of N had no significant effect on WUE and yield component except 1000 kernel weight. Interaction of irrigation levels and N sources concerning yield components and WUE was not significant.