Impact of water requirement on yield productivity of potato crop using lysimeters under arid climate

Abstract

Here, we address the issue of water management for potato (Solanum tuberosum L.) crops under arid conditions in Saudi Arabia over a 5-year period (2011-2016). Daily evapotranspiration for irrigated potato crops (ETc) was determined over a period of three successive seasons. Non-weighing (drainage) lysimeters were used in four regions: Riyadh, Qassiem, Eastern Province, and Al-Jouf. Crop coefficients (Kc) were determined using lysimetric data and an alfalfa-based reference crop evapotranspiration (ETr) during each growing season. Measured (M-ETr) and predicted, (P-ETr) for different regions were compared. Comparisons between M-ETr and P-ETr show higher trends for the measured values in all regions, with averages of 5.72 mm/d, 4.42 mm/d, 5.06 mm/d, and 7.94 mm/d for the Riyadh, Qassiem, Eastern Province, and Al-Jouf regions, respectively. Differences in the ETr and ETc were also observed among the regions due to geographic and climatic variations. In addition, the water-use efficiency of potato crops was generally highest (5.45 kg m-3) in Riyadh and lowest (1.54 kg m-3) in Qassiem. Analysis of projected net returns for irrigated potato production revealed that greater economic potential exists.