Effects of Organic and Inorganic Fertilizers on Nitrogen Mineralization Processes Under Bell Pepper (Capsicum annuum L.) Production

This study aimed to evaluate the effects of organic and inorganic fertilizers on nitrogen mineralization processes in bell pepper production. The experiment was conducted in a screen house at the Teaching and Research Farm of the Federal University of Technology, Akure, Nigeria, using a Completely Randomized Design with three replications. Six fertilizer treatments were applied to the soil: poultry manure, cow dung, neem seed-based fertilizer, single-super phosphate (SSP), urea, and a control. Data were collected on plant height, number of leaves, fruit count, and fruit weight over 12 weeks. Nitrogen mineralization processes, including arginine ammonification, nitrification, and denitrification, were assessed in the Crop, Soil, and Pest Management Laboratory. Soil physical and chemical properties were also analyzed. Analysis of Variance (ANOVA) revealed significant differences in growth parameters among treatments. Plants treated with organomineral fertilizer (NSBF) exhibited the highest plant height, while SSP treatment resulted in higher leaf numbers. Control plants showed the lowest growth metrics. Poultry manure and neem seed-based fertilizer significantly enhanced fruit number and weight, with control plants yielding the least. The results indicate that applying organic fertilizers at recommended rates significantly improved ammonification, nitrification, and carbon content, while reducing denitrification rates in the soil. The integration of organomineral and organic fertilizers not only increased plant height but also positively influenced microbial activity, including ammonifying and nitrifying bacteria. In conclusion, the application of organic fertilizers, particularly neem seed-based fertilizer, is crucial for enhancing soil health and optimizing sustainable bell pepper production.