Effect of irrigation regimes on yield and water use efficiencies of potato

Poor irrigation water management is one of the major factors limiting crop production in Ethiopia. This study was, therefore, conducted at three different locations in the southeastern Ethiopia for 2 consecutive years to investigate the effects of different irrigation depths and intervals with furrow irrigation system on tuber yield, biomass yield and water use efficiency of potato. The treatments consisted of four irrigation regimes. Three of them were determined using FAO-Cropwat 4 Windows 4.3 computer model based on maximum irrigation efficiency and minimum yield loss. The fourth treatment was farmer's practices for each location. The irrigation treatments were laid out in randomized complete block design with 3 replications. Results showed that irrigation regimes determined using FAO-Cropwat 4 Windows 4.3 computer model gave superior tuber and biomass yields and water use efficiencies of potato compared to farmers’ practices at all locations. Higher values of crop and water productivity were obtained when scheduled at application of 20 mm irrigation water every 6 days, 15 mm irrigation water every 7 days and 15 mm irrigation water every 9 days for Sheled, Golja and Lemu areas, respectively. It could be conclude that farmers were over irrigating their farms without equivalent returns. The water saved through optimized irrigation can be used more profitably to irrigate supplemental lands, thus achieving a more efficient and rational use of land and water resources.