遮光、密闭环境对番茄植株蒸腾的影响

Effects of Shading and Obturating on Tomato Transpiration in Greenhouse

在茎热平衡技术测定植株茎流的原理基础上,结合温室内气象数据采集仪器,通过对小温室做遮光、密闭处理,探讨番茄茎流的变化规律。结果表明,密闭温室处理后晴天番茄茎流变化趋势不变,但白天茎流明显减小,此时影响茎流的环境参数除光照外,温室内的大气温度、空气相对湿度以及CO2浓度等都不能忽略。人为改变光照,使茎流随之发生改变,变化规律与光照强度的变化规律相似,所不同的是茎流变化曲线稍稍滞后于光照的变化曲线;茎流随光照的降低而逐渐减小,在时间上有一个延迟。当白天遮光变温室为"黑暗"状态时,茎流缓慢减小,但此时茎流却远远大于夜晚茎流,而且白天温室内"黑暗"状态处理的不同时间段茎流减小的快慢是不一样的。

On the basis of the stem heat balance principle to measure the plant transpiration, with the instruments to collect meteorological data in greenhouse, we studied the variation rules of tomato sap flow under different environmental treatments through shading and obturating environment. The results showed the trend of tomato sunny sap flow was invariable in the obturated greenhouse, but sap flow was obviously diminished. Besides illuminance, temperature, humidity and CO2 concentration were necessary environmental parameters to affect tomato sap flow in greenhouse. Under the treatment of changing illuminance artificially, transpiration rate was changed with illuminance changed, they had similar rules. But the sap flow curve was lagged to the illuminance curve, sap flow was gradually diminished following the illuminance reduced, and had a time delay. When the greenhouse became dark in the daytime, sap flow was gradually diminished, but sap flow value was far bigger than sap flow value at night. When the greenhouse was in the dark in the different time section, the diminished speed of tomato sap flow was different.