Effect of Drip and Furrow Irrigation Methods on Yield and Water Productivity of Onion In East Shewa, Oromia, Ethiopia

Water scarcity in the Central Rift Valley of Ethiopia severely constrains crop production, necessitating efficient irrigation methods. This study evaluated the performance of drip and furrow irrigation for onion production in a 2018 field experiment in Adama district, using a randomized complete block design with three replications. Irrigation method significantly (p<0.05) influenced leaf number, bulb diameter, total and marketable bulb yield, and water productivity. Drip irrigation markedly outperformed furrow irrigation, achieving a total bulb yield of 40.76 t/ha and marketable yield of 37.39 t/ha compared to 37.14 t/ha and 34.05 t/ha, respectively, under furrow irrigation. The bulb diameter under drip irrigation was marginally greater, measuring 5.72 cm compared to 5.70 cm for furrow irrigation. This slight increase reflects the enhanced water efficiency associated with drip irrigation, contributing to marginally larger bulb size. Most notably, water productivity under drip irrigation (12.48 kg/m³) was substantially higher than that under furrow irrigation (7.45 kg/m³), demonstrating greater efficiency in water use. These results indicate that drip irrigation not only increases onion yield but also significantly enhances water productivity, making it a sustainable and water-saving irrigation strategy in this water-limited area. Adoption of drip irrigation could improve crop water use efficiency and contribute to better resource management in the region, addressing critical water scarcity challenges while boosting agricultural productivity.