Integrated Use of Pigeon Pea Residues and Mineral Fertilizers Enhances Rainfed Rice Productivity and Soil Health in a Humid Forest Zone

Abstract Sustainable intensification of rainfed rice systems in sub-Saharan Africa is constrained by low soil fertility and limited access to mineral fertilizers. Integrated nutrient management that combines organic and mineral sources offers a promising pathway to enhance productivity and soil health. A field experiment was conducted in Nkolbisson, Cameroon, to evaluate the effects of pigeon pea (Cajanus cajan L.) biomass and mineral fertilizers on the growth, yield, and soil properties of rainfed rice (variety NERICA 8). The experiment employed a randomized complete block design with four treatments: control (T0), NPK only (T1, 200 kg ha-¹), NPK + pigeon pea biomass (T2, 200 kg ha-¹ NPK + 17 t ha-¹ biomass), and NPK + urea (T3, 200 kg ha-¹ NPK + 100 kg ha-¹ urea). Results showed that T2 significantly (p