Evaluating the Agronomic and Economic Yield of Rice: An Effective Way for Delivering Extension Service

Over the past decade, Africa has experienced the fastest-growing demand for rice globally, underscoring the crop’s significant economic and social importance. Despite this surge in demand, rice yields across the continent remain among the lowest compared to other major rice-producing regions, leading to a heavy reliance on imports. Enhancing rice productivity is therefore critical and can be achieved by optimizing key agronomic practices, such as planting density and seedling age. This study aims to identify the appropriate seedling age and optimal planting density for the NERICA 10 rice variety to maximize grain and straw yields while ensuring high net profitability. The experiment was conducted using a factorial randomized block design with three replications. Seedling age of 21 and 28 days after sowing (DAS) and planting density of 14.5, 20.0, and 25.6 hills/m2 were used as factors. Plant length, stem number, leaf color, heading date, paddy yield, yield components, and straw yield were measured. Data were analyzed using Microsoft Excel and JMP (ver.14.0). The ANOVA result revealed that, there was no interaction effects between seeding age and planting density on growth, paddy yield and yield components, straw yield, and harvest index. However, seedling age had significant effect on plant length, stem number/m2 and headings; while planting density had a significant effect on the number of stems/m2, panicles/m2, and spikelets/panicle. Number of panicles/m2 had also a strong and significant relationship with paddy yield. In paddy yield estimated from yield components, the combination of 28-day-old seedlings with a planting density of 25.6 hills/m² (A2D3) had a 5.4% advantage over the combination of 21-day-old seedlings with a planting density of 20.0 hills/m² (A1D2). However, in Tsubo-Gari sampling, A1D2 outperformed in paddy and straw yield that reached up to 28.3% and 30.2%, respectively, and gave net benefit advantage between 978.35 to 2329.33 USD over alternatives. Applying A1D2 (20.0 hills/m2) decreased seedling cost/ha by 198.7 USD, increased milled rice by 0.98 ton/ha and net profit by 1982.05 USD over A2D3 (25.6 hills/m2). Therefore, A1D2 is recommended as the most effective treatment for optimizing both yield and profitability.