EVALUATION OF DIFFERENT ORGANIC FERTILIZERS ON GROWTH AND YIELD OF BREAD WHEAT (Triticum aestivum L.) AT KULUMSA, CENTRAL ETHIOPIA

<strong>ABSTRACT: </strong>The field experiment was conducted at Kulumsa Agriculture Research station, Kulumsa, Central Ethiopia, to evaluate the effects of commercial organic fertilizers and inorganic N nutrient in wheat cropping systems. The field experiment was conducted a factorial arrangement of two commercial organic fertilizers (Eco-Green, Mela-Organics) and vermicompost, each was tested with four supplementation levels of N (0, 50, 75 and 100%) of the recommended dose of fertilizer in the study area. arranged in a factorial combination laid out in a randomized complete block design (RCBD) with three replications. The results indicated that the highest grain yield (5.23 t/ha) was obtained from MO+100%N, which was statistically similar to that obtained under the VC+100%N (5.00 t/ha), followed by EG+100%N (4.22t/ha). The SPAD scores of 44.6 and 46.2 from VC+100%N and MO+100%N, respectively, recorded where the highest grain and biological yields produced treatments. Compared with chemical fertilizer alone, the application of Eco-Green or Mela-Organics in combination with N fertilizer at higher doses (75% or 100%) significantly increased wheat grain yield by 5-19%, increased biomass yield by 2.6-13.5%. However, sole application of either Eco-Green or Mela-Organics (0%N) and with 50% N level, resulted in grain and biomass yields lower than the conventional practice (CF), with the grain yield reductions ranging from -2.4% to -27.7% and biomass yield reductions from -9.3% to - 20.9%. Similarly, neither the type of organic fertilizers nor the level of inorganic fertilizer supplementation had a significant impact on soil properties except for soil OC. Considering the economic benefit, farmers of the area might be advised to use these commercial liquid fertilizers: Eco-Green in combination with 75%N RDF to achieve comparable wheat yields while reducing chemical fertilizer costs by 25%, whereas Mela-Organics with 100%N. However, since the experiment was done once and only at one location, the research should be repeated involving several other varieties at different locations and over various seasons to reach a conclusive recommendation.