Effects of bio‐slurry and inorganic nitrogen fertilizer rates on wheat yield components, yield, and soil properties

Abstract Maintaining soil fertility and enhancing food production on smallholder farms in Ethiopia remain a major challenge due to severe nutrient depletion caused by continuous cropping with minimal external nutrient inputs. In this context, a field study was conducted on Nitisols over two consecutive cropping seasons (2022–2023) across four locations to evaluate the effects of combining bio‐slurry with inorganic fertilizer on selected soil chemical properties, wheat yield, and economic feasibility. The experiment consisted of 11 treatments comprising sole and integrated applications of liquid bio‐slurry, dry bio‐slurry, vermicompost, and nitrogen fertilizer from urea. Treatments were arranged in a randomized complete block design with three replications. The results showed that the integrated use of bio‐slurry with inorganic fertilizer significantly improved soil chemical properties, wheat yield, yield attributes, and overall economic profitability. The combined treatments increased grain yield by 84%–102% compared to the untreated plot, with the highest yield (3835.2 kg ha −1 ) achieved with 50% N from urea and 50% N from liquid bio‐slurry. Specifically, 75% N from urea combined with 25% N from liquid bio‐slurry produced the highest grain yields in Hula and Basoliben, while 100% N from urea supplemented with 25% N from liquid and dry bio‐slurries provided the maximum yields in Welmera and Ejere districts, respectively. In conclusion, the integrated application of bio‐slurry and inorganic fertilizer enhances soil chemical properties, improves wheat yield and its components, and offers a promising approach for sustainable intensification of smallholder wheat production in Nitisols of the study areas and similar agro‐ecologies.