YIELD AND QUALITY RESPONSE OF MALT BARLEY (Hordeum vulgare L.) VARIETIES TO SEED RATE AND TIME OF NITROGEN FERTILIZER APPLICATION AT BEKOJI, SOUTHEASTERN ETHIOPIA

Malt barley being an important cash crop of the study area, it was cultivated for both home consumption and market purposes. However, its productivity and grain quality is mainly constrained by low yielding vareity, lack of approprite time of N fertilizer application and seed rate recommendation in the study area.Thus, this study was carried out under farmer’s field at Bekoji district during 2018 main cropping season to assess the effect of varieties, time of nitrogen application and seed rate on yield, quality, and to identify economically feasible time of nitrogen application and seed rate in the production area. Factorial combination of two malt barley varieties (Traveler and Ibon174/03), three times of nitrogen application [full rate at basal application (150kg N ha-1), 1/3 at planting remaining 2/3 at tillering, and 2/3 at planting remaining 1/3 at tillering)], and three levels of seed rate (75, 100 and 125 kg ha-1) were laid out in randomized complete block design with three replications. Data of soil samples analysis result shows that the soil was strongly acidic in pH, high in total nitrogen and organic carbon according to Tekalign, 1991 rating both before planting and after harvest. Main effect of variety, time of N application and seed rate had highly significant effect on days to 50% heading, plant height, thousand kernel weight and grain protein content. Days to 90% physiological maturity, grain yield, above ground dry biomass, straw yield, grain protien content and hectoliter weight were significantly affected by main effect of variety and time of N application. Seed rate had significant influence on spike length and number of kernels per spike while spike length was highly influenced by variety. Interaction of variety and time of N application had highly significant influence on days to 50% heading, Days to 90% physiological maturity and plant height while it had significant influence on non effective tillers. Germination energy was highly influenced by interaction of variety and seed rate while interaction of time of N application and seed rate had significant influence on non effective tillers and germination capacity. Interaction of variety, time of N application and Seed rate had highly significant effect on sieve test and grain protein content. Though application of 1/3 recommended N at planting and remaining 2/3 at tillering delays days to 50% heading and Days to 90% physiological maturity of both varieties, Traveler had significantly delayed by 28 days as compared to Ibon 174/03.Traveler values lower non effective tiller at application of 1/3 recommended N at planting and 2/3 at tillering. Higher percentage of sieve test (100%) was recorded at interaction of Traveler variety, 75, 100kgha-1 seed rate and application of N 1/3 at planting and 2/3 at tillering. Germination energy of 99.33% was recorded at interaction of Ibon 174/03 and seed rate of 100kg ha-1.The economic analysis indicates that the combination of Ibon 174/03 variety, application of 1/3 urea at planting and 2/3 at tillering with seed rate of 75 kg ha-1 was economically feasible in malt barley production in the study area.Therefore split application of N fertilize 1/3 at planting and 2/3 at tillering whith a seed rate of 75 kg ha-1 in the production of Ibon 174/03 is economically beneficial.