温室滴灌条件下番茄植株茎流变化规律试验

Experiments on variation of tomato sap flow under drip irrigation conditions in greenhouse

为探明滴灌条件下温室番茄植株茎流速率变化规律及其影响因素,本文采用Dynamax公司开发的包裹式茎流计观测日光温室番茄植株的茎流变化,研究茎流速率的变化规律及茎流速率监测结果的标准化处理技术,探索植株茎流与气象因子的相互关系,分析水分胁迫对番茄植株茎流速率的影响。研究表明,采用单位叶面积上的茎流速率表征茎流变化规律可在一定程度上降低因探头安装位置不同对监测结果的影响;在充分供水条件下,影响番茄植株茎流速率的主要因子是太阳辐射和饱和水气压差,番茄植株的日茎流速率与太阳辐射呈线性关系,与饱和差呈对数关系(R2>0.90,P<0.01);土壤水分状况会明显影响番茄植株茎流状况,茎流速率随水分胁迫加剧而骤减。研究结果证明番茄植株茎流速率经标准化处理后可以真实的反映植株蒸腾规律。

To ascertain the variation law and effect factors of sap flow rate,dynagage sap flow sensors（developed by Dynamax Inc.） were used to measure the sap flow rate of tomatoes in greenhouse,and the variation law and standardized processing technology of sap flow rate were studied in this paper.The relationship between sap flow rate and meteorological factors was discussed,and the effects of water stress on sap flow rate of tomato were also analysed.The results showed that using sap flow rate per unit leaf area to express the variation of sap flow rate could reduce the difference in sap flow rates among various plants.Solar radiation and vapor pressure deficiency were the main factors affecting the sap flow rate of tomato under adequate water-supply conditions,in which there were linear relationship between daily sap flow rate and sun radiation,and logarithmic relationship between daily sap flow rate and vapour pressure deficit（R^2〉0.90,P〈0.01）.Sap flow rate of tomato was affected by soil water moisture.Sap flow rate decreased with soil water stress.Research results show that standardized sap flow rate of tomato can reflect the true transpiration.