Effect of the Irrigation Interval and Nitrogen Rate on Yield and Yield Components of Onion (Allium cepa L.) at Arba Minch, Southern Ethiopia

Onion (Allium cepa L.) is an important cash crop for smallholder farmers in the Central Rift Valley of Ethiopia. However, its productivity low, owing to a number factors including inappropriate irrigation water and nitrogen management. A field experiment was, therefore, conducted at Amibara farm, Arba Minch, Ethiopia, during 2018/19 dry season determine effect interval rate on growth, yield, yield components onion (Bombay Red variety). The treatments comprised four intervals (3, 6, 9, 12 days requirement, ETc) levels (0, 50, 100, 150 kg·N·ha−1). was laid out split-plot design using as main plots rates subplots with three replications. growth parameters, components, final were significantly higher 3 6 (which statistically similar) than 9 intervals. increasing N increased up kg·N·ha−1, but response significant only 100 kg·N·ha−1 crop. contributing showing enhancement frequent rates, had bearing onion. combined gave marketable (30.21 t·ha−1), net return (Birr 288,458 ha−1), marginal (8586%). As such, fertilizer 100·kg·ha−1 may be recommended profitability Gamo Zone, southern