Yield Response and Barley Grain Quality to Nitrogen Fertilization in West Arsi Highland of Ethiopia

Abstract

The malting industry in Ethiopia is often challenged by the availability of barley that meets the quality and quantity requirements set by the industry. Field experiments were conducted to evaluate the effects of mineral nitrogen fertilizer rates on Actual yield and quality response of malt barley varieties and, to determine economic optimum rates of nitrogen fertilizer for the productivity of the crop arranged in randomized complete block design in factorial arrangement with three replications. The treatments are three malt barley varieties, namely Traveler, Ibon and Local and four levels of N (0 kg N/ha, 50 kg N/ha, 100 kg N/ha and 150 kg N/ha. The study revealed that nitrogen fertilization with 150 kg ha-1nitrogen fertilizer rate improved barley yield and quality than the rest nitrogen fertilizer rates. The different barley varieties and nitrogen fertilizer has shown a highly significant (p<0.01) influence on barley yield production. On the other hand, interaction effect of barley varieties and nitrogen fertilizer didn’t show significant variation barley yield production. Moreover, the analysis of variance also revealed that barley varieties have shown a highly significant (p<0.01) influence on barley yield production. The maximum and minimum interaction mean values of actual grain yield were observed from traveler barley variety treated with 150 kg ha-1nitrogen fertilizer rate (2078.10 kg/ha) and Ibon barley variety treated with 0 kg ha-1nitrogen fertilizer rate (1136.30 kg/ha), respectively. In the present investigation, quality parameters increased with an increase in N rates, application of 150 kg N ha-1 gave the highest quality parameters studied except sieve test. While, the quality parameters was less pronounced with the tested varieties and their interaction effect. The partial budget analysis revealed maximum net benefit of (Birr 39147 ha-1) with an acceptable marginal rate of returns (MRR) of 1007.33% with the treatment traveler variety with combination of 150 kg N ha-1. However, the lowest net benefit of (Birr 22726.00 ha-1) was recorded from Ibon barley variety treated with 0 kg ha-1nitrogen fertilizer rate. Both grain yield and protein content increased with increased N rates application of 150kg N ha-1 gave the highest net benefit and marginal rate of return with acceptable grain quality (protein content < 9-12%). Therefore, production of traveler variety with a combination of 150 kg N ha-1 was economical, and uncertainly recommended for production of malt barley in the study area.