Rice Yield and Yield Components as Influenced by Phosphorus and Nitrogen Application Rates in the Moist Savanna of West Africa

Abstract

A two-year field experiment was conducted to evaluate the influence of nitrogen (0, 30, 60, and 120 kg N ha-1) and phosphorus (0, 30, and 60 kg P2O5 ha-1) application on grain yield and yield components of five New Rice for Africa (NERICA) cultivars, their parents, and a check on a degraded soil in the moist savanna of Nigeria. Nerica 14 recorded the highest grain yield of 1.3 mg ha-1compared to the other NERICA cultivars. It also produced significantly (P < 0.05) longer panicles (19.24 cm), higher sink capacity as determined by thousand-kernel weight (30.3 g), and a higher potential for partitioning photosynthates (45.15%) into grains than the other cultivars. N × P interaction effect on grain yield was significant (P < 0.05) with moderate P (60 kg P2O5 ha-1) and moderate N (60 kg N ha-1) resulting in optimum grain yield (1.7 mg ha-1). Thus, moderate N and P were recommended for the production of NERICA varieties in low-input smallholder upland rice production systems of the moist savanna of Nigeria.