Effect of Compost and Nitrogen Fertilizer Rates on Agronomic Performances of Upland Nerica Rice Varieties in Rainforest Agro-Ecology of Nigeria.

Field experiments were conducted at the Federal University of Agriculture, Abeokuta (7⁰9’N lat., and 3⁰21’E long.; 140 m asl) between May – September in 2012 and 2013 planting seasons to study the effect of compost and nitrogen fertilizers on agronomic performances of upland NERICA rice varieties. The experiment was a 2 × 5 × 2 factorial in a Randomized Complete Block Design (RCBD) replicated three times. The treatments were two rice varieties (NERICA 1 and NERICA 2) and five fertilizer rates (0 kg N ha^-1, 40 kg N ha^-1,  80 kg N ha^-1, 10 t compost ha^-1 + 20 kg N ha^-1 and 10 t compost ha^-1 + 40 kg N ha^-1). The rice seeds were treated with Apron Star TM 42 WS and soaked in water for 24 hours and incubated for 48 hours before sowing at a spacing of 30 cm × 30 cm to ensure uniform seedling emergence and good establishment. The plot size was 5 m × 4 m and the C:N of the incorporated compost was less than 20:1. N.P.K and Urea were applied as inorganic fertilizers. The total rainfall in 2012 and 2013 was 850.9 mm and 706.4 mm respectively. The average temperature and relative humidity were 28.3 ^oC and 76.4 % in 2012 and 29.5 ^oC and 73.6 % in 2013 respectively. Data were collected on plant height at maturity, number of tillers at maturity, number of panicles at maturity, panicle length, number of grains per panicle, 1000 grains weight and grain yield. In this trial, application of 10 t compost ha^-1 + 40 kg N ha-1 to NERICA 1 and NERICA 2 produced grain yields of 3.49 t ha^-1 and 3.36 t ha^-1 respectively. It was concluded that application of 10 t compost ha^-1 + 40 kg N ha^-1 to NERICA rice is appropriate for optimum grain yield.