Abstract

Ochwoh V.A.1 , Nankya, E. , Abulo P. , Obuo, P

Rice (Oryzasativa) is increasingly becoming an important food and cash crop in Uganda especially among small-scale holder farmers. Declining soil fertility is thought to be the major production constraint leading to low yields. Nitrogen and phosphorus are the major limiting nutrients to rice production in most rice growing areas in Uganda especially in the Eastern region. A study was conducted to explore the yield benefits associated with nitrogen and phosphorus fertilization. Screen house experiments were conducted at Serere Agricultural and Animal Production Research Institute (SAAPRI). Two upland rice cultivars were grown in soil which had been continuously cultivated. The experimental design was a randomized complete block design arranged in split-split plots with variety as main plots, nitrogen and phosphorus treatments as sub-sub plots. Phosphorus at three rates (0, 25 and 50 kg P2O5 ha-1 ) was applied at planting and Nitrogen at five rates (90, 150, 180 and 240 kg N ha-1 ) was applied two weeks after planting. Nitrogen and phosphorus application significantly (P<0.05) influenced grain yield of upland rice. However, combined application of nitrogen and phosphorus at 150 kg N ha-1 and 25kg P2O5ha-1 respectively, gave highest and significant effect (P<0.05) on grain yield.