Gong Xue-Wen, Liu Hao, Sun Jing-Sheng, Zhang Hao, Li Yong, Wu Xiao-Lei, Cui Jia-Xin
Ying Yong Sheng Tai Xue Bao. 2014 Oct;25(10):2935-43.
It is very significant for muskmelon growth and production to maintain optimal conditions of soil moisture and temperature, especially during blossom and fruit-bearing periods. The object of this study was to analyze the effects of different soil water thresholds (T1: 55% of the field capacity, T2: 65% of the field capacity, T3: 75% of the field capacity, CK: 85% of the field capacity) on soil temperature under mulching-drip irrigation in greenhouse. Moreover, effects of the ratio of soil moisture to heat in the plough layer (0-20 cm) on muskmelon growth and fruit setting were investigated. Results indicated that during the flowering and fruit bearing periods, the order of mean soil temperature in the plough layer for the different treatments was T1 > T2 > T3 > CK. There was an inverse correlation between soil temperature in the plough layer and moisture. The maximum one-day variations for soil temperature on sunny day, rainy day and after irrigation were observed in the soil surface under the plastic film mulch, while the minimum happened in the soil layer of 20 cm outside the mulch. The soil temperature extreme was closely related with soil depth, and the difference in the extreme soil temperature between the soil surface and the soil layers of 10 and 20 cm was significant. The treatment T3, with the fastest plant growth rate, the minimum duration of fruit bearing and the maximum fruit setting rate, could be selected as the optimal treatment, and the ratio of soil moisture to heat in T3 was 1.62 mm · °C(-1). Therefore, taking into consideration the relationship between soil moisture and temperature during flowering and fruit bearing periods of muskmelon under mulching-drip irrigation, the ratio of soil water to heat in the plough layer should be kept at 1.62 mm · C(-1). The result would be very meaningful for drip-irrigated muskmelon production and management in greenhouse in North China.
保持土壤湿度和温度的最佳条件对甜瓜生长和产量非常重要，尤其是在开花和结果期。本研究的目的是分析不同土壤水分阈值（T1：田间持水量的55%，T2：田间持水量的65%，T3：田间持水量的75%，CK：田间持水量的85%）对温室膜下滴灌土壤温度的影响。此外，还研究了耕层（0-20厘米）土壤湿度与热量之比对甜瓜生长和坐果的影响。结果表明，在开花和结果期，不同处理耕层平均土壤温度的顺序为T1>T2>T3>CK。耕层土壤温度与湿度呈负相关。晴天、雨天和灌溉后土壤温度的最大日变化出现在地膜覆盖下的土壤表面，而最小变化出现在地膜外20厘米的土层。土壤温度极值与土壤深度密切相关，土壤表面与10厘米和20厘米土层的极端土壤温度差异显著。处理T3植株生长速率最快，结果持续时间最短，坐果率最高，可作为最佳处理，T3土壤湿度与热量之比为1.62毫米·℃（-1）。因此，考虑到膜下滴灌甜瓜开花结果期土壤水分与温度的关系，耕层土壤水热比应保持在1.62毫米·℃（-1）。该结果对华北地区温室滴灌甜瓜生产和管理具有重要意义。
