Plastic film mulching combined with sand tube irrigation improved yield, water use efficiency, and fruit quality of jujube in an arid desert area of Northwest China

Abstract

Water scarcity and high evaporation are critical factors affecting crop growth and yield. Sustainable production of jujube (Ziziphus jujuba Mill.) plantations is essential for economic development and environmental protection in arid desert areas of Northwest China. However, few studies have investigated how plastic film mulching combined with sand tube irrigation (STI) affects soil surface wetted area, soil water indices, crop water consumption, yield, water use efficiency (WUE), and fruit quality in jujube plantations in arid desert areas. Therefore, a 2-year field experiment was conducted with three levels of STI (SW1, 300 m3 ha–1; SW2, 375 m3 ha–1; SW3, 450 m3 ha–1) and surface drip irrigation as a control (DW3, 450 m3 ha–1). Compared with surface drip irrigation, STI significantly decreased (p < 0.05) surface wetted area, and SW3 significantly increased soil water storage in the 60–100 cm layer as well as the 0–100 cm soil layer. Sand tube irrigation also alleviated the soil water deficit in the 60–100 cm soil layer and each soil layer before irrigation and increased yield by 0.6% and WUE by 27.3% on average. The highest yield and WUE were in SW3 in both years. Crop water consumption of jujube trees increased and then decreased during the growth period in both years and reached a maximum in the fruit swelling period. With STI, vitamin C content increased by 9.8%, soluble protein content by 15.6%, and the sugar to acid ratio by 12.2% in both years. Overall, application of STI increased jujube yields and WUE and improved fruit quality by increasing soil water storage and reducing soil water deficit. Thus, this study demonstrates STI can increase economic and ecological benefits, and also provides guidelines to apply STI and improve agricultural water productivity.