Effect of NPS and Nitrogen Fertilizer Rate on Yield and Yield Components of Food Barley (Hordeum vulgare L.) in Western Oromia, Ethiopia

Inappropriate crop management practices are among the key elements contributed to low productivity of Barley. Moreover, application of balanced fertilizers and nutrient requirements of the crop is the basis to produce more crop yield from the land under cultivation. Accordingly, field experiment was conducted in 2018 & 2019 main cropping season from the mid of July to first of December at Gedo and Shambu research station to identify the optimum amount of NPS and N fertilizer rate and to evaluate the economic profitability of NPS and N fertilizers for Barley production. The experiment was consisted of twenty treatments combined factorial with five NPS (75, 87.5, 100, 112.5 and 125 kg ha-1) and four Nitrogen (17, 23, 29 and 35 kg ha-1) rates keeping the other managements and cultural practices uniform. The experiment was laid out in randomized complete block design with three replication. The pre soil analysis indicated that the soil of experimental area is acidic (pH = 4.99 at Gedo and 4.98 at shambu) and low in available Phosphorus (12 ppm at Gedo and 13 ppm at Shambu). The main effect of days to heading, grain per spike, thousand seed weight and harvest index were not significantly (P>0.05) influenced due to NPS and N rate. Whereas, days to maturity, plant height and panicle length were significantly different (P<0.05) due to the main effects of N rates though not influenced due to NPS rates at Gedo and Shambu. On the other hand, number of effective tiller, grain yield and above ground biomass were highly significantly (P<0.01) influenced due to the main and interaction effect of NPS and N rates at both locations. Among different NPS and N fertilizer rates tested, the combination of 125 NPS and 35 N kg ha-1 rates gave the highest yield thereby resulting in the highest net benefit. Thus, economic analysis indicated that combination of 125 NPS (47.5 P2O5, 23.75 N, 8.75 S kg ha-1) and 35 N kg ha-1 rates on HB -1307 variety gave grain yield (3631.79 kg ha-1) with the net benefit (39849.01 birr/ha) and the highest marginal rate of return (992.16%) are economically feasible alternative to the other treatments. Therefore it is advisable to use combination of 125 NPS and 35N kg/ha rates on HB -1307 variety since economically feasible to the farmers. However, to reach at conclusive idea there is future line of work to get the peak point at which this fertilizer combination showed turning point.