Synergistic Effects of Urea and Slurry-Derived Alkaline Hydrolysis Solution on Soil Fertility, Growth, and Yield of Wheat

Abstract

The integration of organic and inorganic nutrient sources is a cornerstone of sustainable agriculture. This study investigated the synergistic effects of urea and a slurry-derived alkaline hydrolysis solution (AHS) on soil nutrient availability and the agronomic performance of wheat. A pot experiment employing twelve treatments evaluated various combinations of urea (100%, 75%, 50%) and AHS. Results demonstrated that integrated treatments significantly enhanced soil nitrogen, phosphorus, and potassium levels compared to single-source applications. The combination of 100% urea with AHS (T10) proved optimal, recording the highest values for key growth parameters: plant height (cm), spike height (cm), number of spikes per pot, and shoot and root biomass (fresh and dry weight). Morphological analysis revealed that T10 also promoted the most extensive root system and shoot architecture. Treatments with reduced urea (75% and 50%) combined with AHS performed commendably, often surpassing full-dose urea alone, indicating improved nutrient use efficiency. The results are attributed to multiple mechanisms: the AHS likely enhances nitrogen retention and provides a slow-release nutrient source, improves soil physico-chemical properties for better root development, and supplies a balanced spectrum of macro- and micronutrients. We conclude that the integration of urea with slurry-derived alkaline hydrolysis solution is a highly effective strategy for optimizing wheat productivity and soil health, offering a viable pathway to reduce synthetic fertilizer dependency while promoting agricultural waste valorization within a circular economy framework.