关键词: 压砂瓜, 灌溉定额, 需水规律, 作物系数, 水分利用效率

Abstract: Under the conditions of the field experiment, a randomized block design was adopted, and the irrigation quota was set to four treatments： High water 600 m³/hm²（A1）, medium water 450 m³/hm²（A2）, medium water 300 m³/hm²（A3）, low water 150 m³/hm²（A4） and one control without irrigation （CK）. The soil moisture content, crop coefficient, yield, water use efficiency and water demand regulation were studied in the field of pressed sand melon under different irrigation quotas. The results showed that soil moisture content, water consumption and yield increased with the increase of irrigation quota. The soil moisture content of 0~40 cm soil layer was the highest under A1 treatment, and the lowest under CK treatment. Comparing soil moisture content in different soil layers, the fluctuation of 0~10 cm was the most obvious, the fluctuation of 10~20 cm and 20~30 cm was the second, and the fluctuation of 30~40 cm was the least; water consumption at different growth stages under different treatments was manifested as fruit expansion stage>flowering and fruit-setting stage>extension stage> seedling stage> maturity stage, the daily water consumption was flowering and fruiting stage>fruit expansion stage> extension stage > seedling stage > maturity stage; the crop coefficient of each growth stage was flowering and fruit-setting stage > fruit expansion stage > extension stage > seedling stage > maturity stage. The water use efficiency increased with the increase of irrigation quota within a certain range, but the water use efficiency decreased when the irrigation amount was too high. Medium water treatment A2 had the highest water utilization efficiency, and the water resources were fully utilized. In consideration of water saving, water use efficiency and economic value, medium water treatment A2（450 m³/hm²） was the most suitable irrigation quota.

Key words: pressed sand melon, irrigation quota, water demand regulation, crop coefficient, water use efficiency