Evaluation of Surface Drip Irrigation Systems Focusing on Water-use Efficiency in High-value Vegetable Production in the Semi-arid, Windy Region of the Texas High Plains

The increased depletion of groundwater from the Ogallala Aquifer raises questions about the environmental and economic sustainability of conventional field crop production in the Texas High Plains in the United States. We aimed to assess the crop water-use efficiency (WUE) of surface drip irrigation (SDI) systems for high-value vegetable production in this region. Two irrigation treatments - SDI without plastic mulch (CTRL) and SDI with plastic mulch (MCH) - were assigned as the main plots, which were split into sweet corn, chili pepper, and tomato sub-plots. Crop evapotrans-piration (ETc) and the WUE outcome of each plot were evaluated. Early growth of crops was promoted with MCH, but by harvest time there was no difference between MCH and CTRL in terms of growth and biomass for corn and tomatoes. MCH reduced the amount of water required for irrigation by about 7.4% but did not reduce ETc. MCH increased the WUE of peppers, but not of corn or tomatoes. The marketable yields of corn and peppers reached the state average, but tomatoes were severely damaged by tomato spotted wilt virus, and only those with MCH produced marketable yields equal to the state average. This study demonstrated the feasibility of high-value vegetable production in the Texas High Plains using SDI, and pepper, with MCH, showed the greatest potential.