Influence of integrated nutrient sources of nitrogen on productivity of lowland rice varieties in a derived savannah ecology of Nigeria

Inorganic fertilizers are expensive and beyond the reach of resource-constrained rice farmers in Nigeria, where nutrition affects rice productivity. Use of integrated nutrient management technologies minimize the harmful effects of climate change on lowland rice. Consequently, this study evaluated the effects of integrated nutrient sources on NERICA L-34 and ARICA 3 in years 2017, 2018 and 2019. The nutrient sources were 100 kg N ha −1 of NPK, 75 kg N ha −1 (NPK) + 25 kg N ha −1 (manure), 50 kg N ha −1 (NPK + 50 kg N ha −1 (manure), 25 kg N ha −1 (NPK) + 75 kg N ha −1 (manure), 100 kg N ha −1 (manure) and control (no fertilizer). The treatments were arranged in split-plot and laid out in Randomized Complete Block Design and replicated thrice. Economic efficiency of the system was assessed using cost and return analysis. Results indicated that the highest economic parameters were recorded when 25 kg N ha −1 (NPK) + 75 kg N ha −1 (manure) was applied. The study concluded that economic parameters by 25 kg N ha −1 (NPK) + 75 kg N ha −1 (manure) nutrient source produced the highest economic parameters during the study and is thus recommended for adoption and utilization by rice farmers.