Improving Agricultural Water Productivity with Alternate Furrow Irrigation in Semi-Arid Conditions of Northern Ethiopia

The major production constraint in arid and semi-arid areas is scarcity of irrigation water. Thus, improving the management of irrigation water is very crucial to reduce water losses and thereby enhance water use efficiency. Hence, this research was conducted to evaluate the effect of Alternate Furrow Irrigation (AFI) on yield, water use efficiency and economic return of Onion at Hamedo irrigation scheme as compared to Conventional Furrow Irrigation (CFI), at different levels of water application (100, 80 and 60% of crop evapotranspiration (ETc)). Results indicated that AFI maintained almost similar bulb yield but with up to 50% reduction in irrigation amount when compared to CFI. The maximum marketable bulb yield obtained at 100% ETc with CFI was 22.9 ton/ha which is not statistically significant with that of obtained under AFI (20.8 ton/ha). However, the WUE of onion under AFI at 100% ETc was higher (7.12 kg/m3) than that of CFI at 100% ETc (3.9 kg/m3). Moreover, the amount of water saved by AFI, at both levels of water (80 and 60% ETc), was also much higher (293.8 - 413.1mm) than even that of 60% ETc under CFI (238.4mm). Overall, under limited water resources, AFI can reduce the costs associated with labor and pumping to the field. Therefore, it can be recommended that AFI is a practical technique to improve agricultural water productivity for irrigated crops in the study area and other similar agro ecologies.