Effects of Air–Water Interaction on Water Consumption, Fruit Yield, and Quality of Drip-Irrigated Processing Tomatoes

Abstract

To seek the optimal combination of water–air for drip irrigation processing tomatoes in Northern Xinjiang, China, field experiments consisted of four irrigation levels, and two types of gas-filling methods were proposed. Throughout the whole growth period, the water consumption by physical aeration and chemical aeration increased by 13.65% and 9.27%, respectively compared with the nonaerated treatment. Under the conditions of physical aeration, the processing tomato fruit yield and irrigation water use efficiency (IWUE) increased by 8.14% and 4.74%; while by chemical aeration, they increased by 7.91% and 4.61%, respectively. Physical aeration had the most prominent role in increasing the contents of organic acid, soluble solids, soluble sugar, lycopene, and VC in processing tomatoes. The presented indicators show that the effect of physical aeration was better than that of chemical aeration. Physical aeration in combination with different irrigation levels, the 4,950 m3·hm−2 irrigation level gave the highest yield of processing tomato, whereas the highest IWUE was obtained in the 4,500 m3·hm−2 irrigation treatment, and the quality parameters of processing tomatoes at the 4,500 m3·hm−2 irrigation level performed better than those at the 4,950 m3·hm−2 irrigation level. To take into account the requirements of processing tomatoes for maximum IWUE and fruit yield and quality, the entropy weight method was used to determine that the irrigation water volume of 4,500 m3·hm−2 under the conditions of physical aeration can be used as a suitable water and air combination pattern for processing tomatoes in drip irrigation in Northern Xinjiang.