Effects of irrigation levels and nitrogen fertilizer rate on grain yield of wheat (Triticum aestivum) at Amibara, Middle Awash, Ethiopia

For three years, the response of wheat grain yield to varying amounts of nitrogen fertilizer and different levels of irrigation was investigated. Three levels of irrigation (100, 75, and 50%ETc) and five nitrogen rates (0, 23, 46, 69, and 92 kg/ha) were used in a split plot design. Irrigation and nitrogen levels both had a considerable impact on wheat grain yield, but there was no interaction between the two. The threeyear combined analysis result revealed that the maximum grain yield of wheat was recorded at 92 kg/ha nitrogen rate and 100%ETc irrigation treatment. The minimum was obtained from no application of nitrogen and 50%ETc irrigation treatment. The study revealed that the above ground biomass and grain yield of wheat increased with the increasing rates of nitrogen fertilizer and the full application of irrigation. The partial budget analysis revealed that an application of 100%ETc and 46 kg/ha nitrogen fertilizer gave the maximum marginal rate of return and optimum net benefits. Therefore, application of 100%ETc irrigation and 46 kg/ha nitrogen is recommended for optimum returns of irrigation and nitrogen fertilization of wheat in the study area.