Agronomic Performance and Economics of Awot Upland Rice (Oryza sativa L.) Influenced by Fertilizer Application and Weed Control Methods

Abstract

Awot is one of the upland rice varieties favored by local folks, hence, ways to improve its production is essential. The field experimental research aims to assess the economics of production of Awot upland rice to levels of N fertilizer and weed control methods. The study was consisted of two experimental factors laid out in Split-Plot Design (SPD) with three replicates. Factor A (main plots) involved levels of N fertilizer application such as N1 – Control (no N application), N2 – 1/2 RR (40 kg N/ha , N3 – RR (80 kg N/ha), and N4 – RR + 1/2 (120 kg N/ha) while Factor B (subplots) included no weeding (Wo), pre-emergence herbicide + hand weeding once (W1), post-emergence herbicide + hand weeding once (W2), farmer’s practice—2 times hand weeding (W3) and pre-emergence + post-emergence herbicides (W4). The data gathered were subjected to the Analysis of Variance using the F- test and the DMRT, interpreted at 5% and 1% levels of significance.

Almost all growth and yield parameters of Awot upland rice variety applied with varying N levels varied significantly except on the number of days to flowering. Similarly, weed control methods had influenced the growth and yield parameters of upland rice in terms of biomass, panicle length, and grain yield. The interaction effect was observed in terms of the number of productive tillers, panicle length, and grain yield. As to weed assessment, the N levels and weed control methods had influenced the number of weed species, weed population, and weed biomass. The interaction effect was also observed on the two factors studied on these parameters. The highest ROI was observed from plots applied with 120 kg N/ha, while the use of pre- and post-emergence herbicides gave the highest ROI.