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Development of transpiration stream sensor and stress responses in plants

蒸腾流传感器的开发和植物胁迫反应

基本信息

批准号：
09650181
负责人：
UENO Hisanori
金额：
$ 1.66万
依托单位：
Kanazawa University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

项目摘要

Water transport in green plants is important for maintaining plant life and numerical researches taking account of the anatomy of plants have been presented in the view of agricultural engineering and plant physiology. Recently, in crop science and horticulture the effects of the environment on the transpiration stream have been investigated quantitatively. However, there is not enough of quantitative and reliable data based on simultaneous measurement for the rates of the transpiration and absorption because of the lack of a simple and accurate method of measurement under natural conditions. Water movement must be investigated more thoroughly in the connection between these data and plant physiology.Modeling and measurement of driving forces and resistances to water movement :To investigate a mechanism of transpiration stream, the suction pressures for water absorption and transfer resistances of three organs, i.e., leaves, stem, roots, were measured by the potometer method. Suction p … More ressures due to the leaves and roots were determined from the conditions of zero-absorption rate, which was attained by the reduction of the hydrostatic pressure head applied on the roots immersed in the water. Three values of the resistances were estimated by the three kinds of experiments. Based on the experimental results, a simple model for water absorption was developed. Some results predicted by the model were well consistent with measured data.Development of a method of simultaneous measurement for transpiration and absorption rate :In the developed method in the case of plants immersed in the water, two electronic balances were used. A balance weighs water in the bath for measuring the absorption loss, and the other balance weighs the only plant, root of which are to be floated in the water bath, for measuring the absorption minus transpiration loss. Transpiration loss of water is obtained by the sum of two balances. In the case of the roots in the soil, a potted plant in the soil is to be floated in the water bath. In this case the effect of buoyant force on absorption must be considered. Using these method, instantaneous and accurate measurements were attainable.Experiments of plant responses to environment :Step responses of water movement to illumination and atmospheric temperature, and to cutting of roots were examined, using the above-mentioned method. Relation between the transpiration and absorption, aspect of pulsation of water movement were investigated by using the plants in the water and those in the soil. It was noted that the transpiration rate showed the large overshoot from the steady value and in phase lag to the absorption rate. On the other hand, those phase relation by cutting the roots was conducted reversely. Less

绿色植物的水分输送对维持植物的生命具有重要意义，从农业工程和植物生理学的角度对植物的水分输送进行了数值研究。近年来，在作物科学和园艺学中，对环境对蒸腾流的影响进行了定量研究。然而，由于缺乏一种简单而准确的自然条件下的测量方法，因此没有足够的基于同时测量蒸腾速率和吸收率的定量和可靠的数据。在这些数据和植物生理学之间的联系中，必须更彻底地研究水的运动。水分运动动力和阻力的建模与测量：为探讨蒸腾流的机理，采用测水计法测量了叶片、茎、根3个器官的吸水压力和水分运动阻力。在吸收率为零的条件下，通过减小浸没在水中的根所受的静水压头来确定叶片和根所受的压力。通过三种实验，估计了三个电阻值。在实验结果的基础上，建立了一个简单的吸水模型。模型预测的部分结果与实测数据吻合较好。开发一种同时测量蒸腾和吸收率的方法：在开发的方法中，在植物浸泡在水中的情况下，使用了两个电子天平。一个天平称水浴中的水，用于测量吸收损失，另一个天平称唯一的植物，其根要浮在水浴中，用于测量吸收减去蒸腾损失。蒸腾损失的水分由两个平衡的总和得到。在根在土壤中的情况下，土壤中的盆栽植物将在水浴中漂浮。在这种情况下，必须考虑浮力对吸收的影响。使用这些方法，可以实现即时和准确的测量。植物对环境响应的实验：采用上述方法，研究了水分运动对光照、大气温度和根系切断的阶跃响应。以水中植物和土壤植物为研究对象，研究了蒸腾与吸收的关系以及水分运动的脉动方面。蒸腾速率表现出较稳态值较大的超调和对吸收率的同相滞后。另一方面，切断根的相位关系是反向进行的。少