Response of Greenhouse Crop Ecophysiology, Water Consumption and Yield to Ventilation Environment Regulation

Under the condition of greenhouse cultivation, the influence of environmental regulation on crop physiological and ecological indexes, water consumption process and yield cannot be neglected. Studying the changes of each index under different opening time and state of ventilation can further improve the theory of greenhouse environmental regulation and control and realize the rational utilization of water resources. Three ventilation modes were set up for drip irrigation tomato in sunlight greenhouse in North China. They were opening North window and top window (T1), opening North window, south window and top window (T2) and opening North window and south window (T3). The effects of different ventilation modes on greenhouse environment, physiological ecology, water consumption and yield of tomato were analyzed. The results showed that: (1) The fluctuation of water surface evaporation under different ventilation modes was consistent during the whole growth period, but the cumulative evaporation was T2 > T1 > T3. The ventilation mode of T2 treatment was beneficial to alleviate indoor high temperature hazards, which was 3–4% and 3–5% lower than the average temperature of T1 and T3, but the higher temperature of T1 treatment was beneficial to the early fruit formation. (3) T2 had the highest yield, 147.15 t/hm 2 , 11.71% higher than T1 and 13.52% higher than T3, and the water consumption was the least, 143.73 m 3 /hm 2 , which was higher than T1 and T3, respectively. Water use efficiency (WUE) and irrigation water use efficiency (IWUE) were 1023.81 (kg/m 3 ) and 1719.26 (kg/m 3 ), respectively. So the ventilation treatment in the early stage is to open the North window and the roof window, and the ventilation treatment in the middle and late stage is to open the North window, the south window and the roof window simultaneously. The purpose of this paper is to perfect the theory of greenhouse environmental regulation and control, and to provide reference for further rational layout of greenhouse vents.