温室通风控水条件对番茄耗水特性及产量的影响

确定温室最佳通风和灌水量可改善室内小气候，减少耗水量并提高果实产量，对进一步优化温室作物灌溉制度至关重要。通过开启温室不同位置通风口设置2种通风处理（T1：开启北窗和顶窗；T2：开启北窗、顶窗和南窗），同时参考20 cm标准蒸发皿的累积蒸发量，设置2种水分处理（水面蒸发系数分别为0.9（K0.9）和0.5（K0.5）），进行完全组合设计，分析了不同通风和水分对温室覆膜滴灌番茄生理生态、耗水特性及产量的影响，采用通径分析法探讨了影响番茄茎流速率的主控因子。结果表明：1）T2的日均风速明显高于T1，但温度和湿度却相反；2）全生育期内，T1K0.9和T2K0.9的耗水量分别为282.4和278.4 mm，高于T1K0.5（201.8 mm）和T2K0.5处理（202.5 mm）；利用通径分析确定气象因子对茎流速率的综合影响程度由大到小依次为净辐射、温度、相对湿度和风速，其中净辐射对茎流速率的影响主要表现为直接作用，而温度、风速及相对湿度主要表现为间接作用。3）不同通风和水分条件影响了番茄的生长发育和产量形成， T2K0.9的平均单果质量为0.15 kg，水分利用效率为53.0 kg/m3，总产量达到147.6 t/hm2。建议华北地区日光温室通风控水管理参考T2K0.9（开启北窗、顶窗和南窗，水面蒸发系数取0.9）可提高番茄的产量和水分利用效率。

Effects of greenhouse ventilation and water control conditions on water consumption characteristics and yield of tomato

Optimal ventilation and irrigation water are highly essential to optimize irrigation systems for greenhouse crops, particularly on indoor microclimate, water saving, fruit yield, and quality. In this study, a field experiment was conducted at the Xinxiang Comprehensive Experimental Base of the Chinese Academy of Agricultural Sciences from March to June 2020. Two ventilation treatments were set (T1: opening the north and top windows; T2: opening the north, top and south windows) under various vents opening at different locations in the greenhouse. Two moisture treatments (the water surface evaporation coefficients were 0.9 and 0.5, respectively) referred to the cumulative evaporation of a standard 20 cm evaporation dish. A fully combinatorial design was used to divide into four treatments (T1K0.9, T1K0.5, T2K0.9, T2K0.5) in total. An investigation was also made on the effects of different aeration and moisture on the physiological ecology, water consumption characteristics, and yield of mulched drip tomatoes. Path analysis was finally utilized to explore the ranking of main control factors affecting the stem flow rate of tomatoes under three typical weather conditions (sunny, cloudy, and overcast). The results showed that: 1) The temperature and relative humidity were much lower inside the T2 compartment on sunny or cloudy days, compared with the T1 compartment. Nevertheless, the temperature was basically the same inside two compartments on overcast days, whereas, the relative humidity inside the T2 compartment was higher than that in the T1 compartment. 2) Crop water consumption depended mainly on water treatments and root development during the whole reproductive period. Specifically, the water consumption of T1K0.9 and T2K0.9 were 282.4 and 278.4 mm, respectively, higher than that of T1K0.5 (201.8 mm) and T2K0.5 treatments (202.5 mm). The water consumption intensity of each treatment at different fertility stages was ranked in order: mid-fertility > rapid growth period > late fertility > early fertility, among which the mid-fertility stage presented the highest water consumption. The daily water consumption intensities of T1K0.9, T1K0.5, T2K0.9, and T2K0.5 reached 3.4, 2.3, 3.9, and 2.3 mm/d, respectively. Path analysis was utilized to determine the comprehensive impact of meteorological factors on the sap flow rate. The parameters were ranked in order: net radiation > temperature > relative humidity > wind speed at 2 m. Furthermore, there was a direct correlation between the net radiation and sap flow rate, whereas an indirect correlation was found among temperature, relative humidity, and wind speed at 2 m. 3) Different ventilation and moisture conditions posed significant effects on the growth, development, and yield of tomatoes. The leaf area index showed in the pattern of T2K1 > T1K1 > T2K2 > T1K2 in the peak period of water demand, transpiration rate showing T2K0.9 > T2K0.5 > T1K0.9 > T1K0.5. The average fruit mass of T2K0.9 was 0.15 kg, while the water use efficiency was 53.0 kg/m3, and the total yield reached 147.6 t/hm2, 5.8%, 18.8%, and 23.6% higher than those in the T1K0.9, T1K0.5, and T2K0.5 treatments, respectively. Therefore, it can be recommended that the T2K0.9 treatment is preferred to improve the yield and water use efficiency of tomatoes for ventilation and water control in the solar greenhouses in North China.