Nitrogen Use Efficiency and Performance of Wheat Crop Through Application of Urea Stable and Conventional Urea in Vertisols of Ambo District

Nitrogen is the most yield liming nutrient that can be highly soluble and lost through leaching, volatilization and denitrification. In this view an experiment was conducted to determine the effects of urea stable and convectional urea on nitrogen use efficiency and crop performance of wheat in Vertisols of Ambo District, west Shewa Zone. The experiment was laid out in randomized complete block design with three replications. The treatments were different rate of urea stable and convectional urea applied at planting and in split: (Control, 23 kg N ha -1 from urea stable applied once at planting, 23 kg N ha -1 from urea stable in split application, 46 kg N ha -1 from urea stable in split application, 46 kg N ha -1 from urea stable applied once at planting, 46 kg N ha -1 from urea in split application, 69 kg N ha -1 from urea stable in split application, 69 kg N ha -1 from urea in split application, 69 kg N ha -1 from urea stable applied once at planting). Agronomic use efficiency was significantly varied among applied urea stable and convectional urea during first year. Significantly higher (32.77 and 40.8 kg grain/ kg N applied) agronomic efficiency of wheat from farm one (1) and two (2) were recorded by application of 23 kg N ha -1 from urea stable in split form. Mean grain yield, dry biomass, harvest index, plant height and spike length of wheat were significantly affected with application of urea stable and convectional urea. The highest mean spike length (6.6cm), plant height (80cm), harvest index (45%) and thousand seed weight (45g) were recorded from split application of 69 kg N ha -1 in the form of urea stable fertilizer. Wheat grain yield of 3623 kg ha -1 and dry biomass 8921 kg ha -1 were recorded from split application of 69 kg N ha -1 from conventional urea fertilizer. Statistically significant difference of yield and yield components of wheat were not observed by applying similar rate of urea stable and convectional urea. Therefore, urea stable and convectional urea could be used as alternatively for wheat production in study area.