Combination of Organic and Inorganic Fertilizer Improves Wheat Yields and Soil Properties on Nitisols of Central highlands of Ethiopia

Abstract

A field experiment was conducted for three consecutive cropping seasons (2015-2017) on farmers’ fields in Welmera district of Oromiya Regional State with the objective of quantifying the effect of organic and inorganic fertilizers on growth and yield of wheat and soil chemical properties. The treatments included eleven selected combinations of organic and inorganic nutrient sources including farm yard manure, Compost, Nitrogen and Phosphorus application. The experimental design was randomized complete block with three replications. Results showed that wheat yield, yield components and soil chemical properties were significantly affected by the application of organic and inorganic fertilizer sources. The highest wheat(Triticum aestivum L.) grain yield (4278.1 kg/ha) and biomass yield (1385.5kg/ha) were obtained from the applications of half doses of compost which is based on recommended N equivalent and half doses of the recommended nitrogen and phosphorus fertilizers (30kg/ha N and 34.5kg/ha P that half dose contains) followed by 4269.4 kg/ha and 13711.7 kg/ha for grain yield and biomass yield, respectively, due to the application of the full recommended N and P rates (60kg N/ha and 69kg P/ha)from inorganic fertilizers. Application of organic fertilizer improved organic carbon from 1.08% to 1.86%, total N from 0.14% to 0.28%, available phosphorous from 6.35ppm to 18.14pmm and pH from 4.04 to 5.08. The highest marginal rate of return was obtained from application of 75% compost (based on equivalent N rate) plus 25% N and P, which is economically the most profitable on Nitisols of the central Ethiopian highlands. Keywords : Compost, Farm yard manure, Nitisols, Nitrogen, Phosphorus DOI : 10.7176/JBAH/9-4-02