Shallow burial of drip irrigation tape improves the water use efficiency of potatoes in semi-arid areas

Water scarcity constrains potato production in arid and semiarid regions. Therefore, improving water use efficiency is critical for sustainable potato production. We use Inner Mongolia of China as a case site to examine the effects of shallowly burying drip irrigation tape (SSI) on water use efficiency over four years by comparing it with surface drip irrigation (SI) in terms of tuber yield, irrigation water productivity (WP_I), root dry weight, leaf area index (LAI), dry matter accumulation of potatoes, and evapotranspiration. SSI reduced evaporation at early potato growth stages compared to SI by 8-26%. In comparison, SSI increased potato root dry weight after tuber initiation by 19.0%, which resulted in that LAI, plant dry matter accumulation from the tuber bulking to starch accumulation increased by 19.5% and 22.6%, respectively. Finally tuber yield under SSI increased by 8.0%, and the average WP_I increased by 7.8%, compared to that under SI. Therefore, SSI can improve the water use efficiency of potatoes in semiarid region by reducing evaporation and enhancing potato root growth. This is significant for sustainable potato production in such an area.