Nutrient Use Efficiency and Grain Quality of Malt Barley (Hordeum vulgare L.) Varieties in Response to Nitrogen Fertilizer in Southeastern Ethiopia

Abstract

The expansion of brewing industries in Ethiopia has been inducing a growing demand for the supply of malt with optimum kernel protein content. However, the supply has been constrained by the unavailability of sufficient volumes of acceptable quality of malting barley grain to meet the ever-increasing demand. In this regard, field experiments were conducted in the southeastern Ethiopian highlands to evaluate the combined effects of six fertilizer levels (0, 11.5, 23, 34.5, 46, and 57.5) N kg ha^-1 and three malt barley varieties (Fanaka, Ibon and Holker ) on the yield, quality and nutrient use efficiency of malting barley. The experiment was laid out in a randomized complete block design with three replications. Application of 11.5, 23, 34.5, 46 and 57.5 N kg ha^-1 increased the grain yields by 1010.3, 1065.9, 1288.1, 1421.3, and 1777.6 kg ha^-1 and economic benefits by 31 %, 30.4 %, 32.9%, 33.16% and 33.38% respectively, for each increment of on N fertilizer, when compared to the control treatment. The production of malting barley with improved yield, optimum kernel protein concentrations and enhanced economic benefit was attained through 57.5 and 46 N kg ha^-1 as first and second option respectively in the study area. Thus, to improve the likelihood of acceptance of malting barley by malting industries, growers are recommended to select low-protein containing varieties and decide application of N fertilization based on soil test results.