Effect of Agronomic Management Practices on the Grain Yield of Lowland Rice (Oryza sativa) in Rainforest Agro-Ecology of Nigeria.

Field experiments were conducted in an inland valley at the Federal University of Agriculture, Abeokuta (7⁰9’N lat., and 3⁰21’E long.; 140 m asl) during the late cropping seasons of 2012 and 2013 to study the effect of agronomic management practices on the grain yield of lowland rice. The experiment was a 2 × 2 × 2 factorial in a Randomized Complete Block Design (RCBD) replicated three times. The treatments were rice varieties (WITA 4 and ITA 368) and spacing (20 cm × 20 cm ; 40 cm × 40 cm). The 10 day old rice seedlings raised in the nursery following the best practices were carefully transplanted at two seedlings per hill. Maize stalks and leaves left over from early season cultivation on the upland were used as mulch to encourage soil microbial activities. The inland valley holds enough moisture throughout the growing period. The average temperature and relative humidity in the dry season were 32.4 ^oC and 58.2 % in 2012 and 34.7 ^oC and 54.9 % 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. WITA 4 and ITA 368 planted at 20 cm × 20 cm produced grain yields of (4.32 t ha^-1 and 4.68 t ha^-1) and (3.61 t ha^-1 and 3.79 t ha^-1) in 2012 and 2013 respectively. It was concluded that farmers should be encouraged to cultivate WITA 4 in inland valley to obtain high grain yield.