Productivity and Economic Performance of NERICA Varieties under Two Harvest Modes and Rainfall Intensities in Uganda

Abstract

The productivity of upland rice is highly determined by the available soil moisture and nutrients. Droughts highly influence yields especially in the second 30 days growth period. A field experiment was conducted at the Uganda National Agricultural Research Institute, Ikulwe station during 2018B and 2019B seasons to determine the productivity and economic returns of four rice varieties under two harvest modes and rainfall intensities. The treatments included NERICA 1, 4 & 6 and NAMCHE 2 given 80 kg N and 30 kg P ha-1. Treatments were replicated three times under a randomised complete block design.  Data was collected on plant height, leaf number, leaf length, leaf width and number of tillers during vegetative stages in all treatments. The panicles m-2, sink size, panicle filling percentage and grain yields were determined at harvest. All the yield attributes and grain yield reduced during the droughty 2018B relative to the rainy 2019B. On the contrary, the number of tillers reduced in 2019. Correlation coefficient (r) for spikelets per m-2 were significant (>8.0) and positive (0.86) to grain yield during 2018 but were lower (0.13) in 2019. The r values were also positive, but not significant, for panicles m-2 (0.76) and for percent filled panicles (0.23) with respect to grain yield during 2018 and 2019 respectively. NERICA 4 & 6 produced higher grain yield under both moisture stress and high rainfall conditions. The results indicate that NERICA 4 and 6 varieties could be adopted and harvested at 75 days after rice emergence (DAE) for NERICA 4 and at 75 DAE and 90 DAE for NERICA 6 under low (630 mm) rainfall or harvested once at 90 DAE given high (1,500 mm) rainfall to get higher yields and Returns on Investment.