Effect of type and rate of urea fertilizers on nitrogen use efficiencies and yield of wheat (Triticum aestivum) in Northern Ethiopia

Abstract A field experiment was conducted to evaluate the effect of type and rate of urea fertilizers on nitrogen use efficiency and yield of wheat (Triticum aestivum) in northern Ethiopia. The field experiment comprised five treatments, i.e. three treatments with the application of super granular urea (SGU) (application rates of 23, 46 and 69 kg N ha−1), one treatment with the application of conventional urea (CU) fertilizer (46 kg N ha−1) and one control (without any N fertilizer application) laid down in a randomized complete block design. All experimental units were supplied with a uniform rate of 46 kg phosphorus (P) ha−1in the form of triple superphosphate (TSP) at planting time. At harvest, the crop was partitioned into straw and grain for the determination of N concentration, uptake of N fertilizer recovery and use efficiency. Application of SGU fertilizer has affected the grain and straw N content and uptake of the crop. These showed an increasing trend with increasing N rate where the maximum was obtained at the highest rate of SGU (69 kg N ha−1) application. The application of 46 kg N ha−1 via SGU fertilizer revealed a yield advantage of 497.67 kg ha−1 compared to the application of 46 kg N ha−1 with conventional urea (CU) fertilizer. As a general conclusive remark, the results of the current study show that the application of SGU fertilizer can increase yield and nitrogen use efficiency of wheat crop compared with CU fertilizer. Moreover, the application with 46 kg N ha−1 with SGU fertilizer was the optimum rate.