RUI: Quantitative Relationships for Water and Solute Transport in Plant Tissue

Ortega博士以前的理论和实验研究的总体目标是描述单个真菌和植物细胞的生长（扩大）和吸水的定量关系的发展。 这些研究产生了三个同时和相互关联的控制方程（扩增生长方程），描述了细胞壁延伸，吸水和膨压的行为。 拟议的研究的总体目标是扩展（修改，适应和/或增强）以前建立的增广生长方程，研究细胞壁的延伸，水的运输和溶质在植物组织中的运输。 一些长期目标是（a）建立描述生长的植物组织、植物器官和整个植物的壁延伸行为、水运输行为和溶质运输行为的控制方程，（B）确定包括生物力学和生物物理参数的大小和行为，以及（c）阐明用于控制这些参数的大小和行为的生物机制。 体积弹性模量E是一个重要的生物力学参数，它控制着膨压变化时发生的弹性细胞壁延伸的量，并参与调节植物细胞和植物组织在动态条件下的水分运输，如生长、昼夜循环（昼夜模式）和水分胁迫时期。 重要的是，E是膨压E（P）的函数。 因此，综合模型的水transnasport，生长和植物的反应，昼夜模式和水分亏缺，必须采用准确的值E和考虑其对膨压的依赖。 由于压力室法不能直接测量压力，因此很难获得Estat的精确估计值，也很难确定它对压力的依赖性。 最近，Ortega博士开发了一种新的压力探针方法（直接测量膨压）来确定Estat及其对膨压的依赖性Estat（P）。 利用这种新的压力探针法测定了豌豆茎脱水和复水过程中的Estat（P）。 将比较从脱水和再水化实验获得的结果，以确定豌豆茎组织中细胞的压力-体积关系是否存在显著的滞后。 也不知道Estat（P）与Einst（P）的比较。 建议研究确定相同细胞和组织的Estat（P）和Einst（P），以阐明两个值之间的关系。

9507240 Ortega The overall goal of Dr. Ortega's previous theoretical and experimental research was the development of quantitative relationships that describe growth (enlargement) and water uptake of single fungal and plant cells. These inestigations have produced three simultaneous and interrelated governing equations (Augmented Growth Equations) that describe the behavior of cell wall extension, water uptake, and turgor pressure. The overall objective of the proposed research is to extend (modify, adapt, and/or augment) the previously established Augmented Growth Equations to study cell wall extension, water transport, and solute transport in plant tissue. Some long-term objectives are (a) to establish governing equations that describe wall extension behavior, water transport behavior, and solute transport behavior for growing plant tissue, plant organs, and whole plants, (b) to determine the magnitude and behvior of the inclusive biomechanical and biophysical parameters, and (c) to elucidate the biological mechanisms used to control the magnitude and behavior of these parameters. The volumetric elastic modulus, E, is an important biomechanical parameter that controls the amount of elastic cell wall extension that occurs when the turgor pressure changes, and participates in the regulation of water transport in plant cells and plant tissue during dynamic conditions such as growth, day/night cycles (diel patterns), and periods of water stress. Importantly, E is a function of the turgor pressure, E(P). It follows that comprehensive models of water trnasport, growth, and plant responses to diel patterns and water deficits, must employ accurate values for E and account for its dependence on turgor pressure. It has been difficult to obtain accurate extimates of Estat, and to determine its dependence on pressure, using the pressure chamber because the pressure is not measured directly by the pressure chamber method. Recently, Dr. Ortega has developed a new pressure probe method (whi ch measures the turgor pressure directly) to determine Estat and its dependence on turgor pressure, Estat(P). Investigations are proposed to use this new pressure probe method to measure Estat(P) for dehydrating and rehydrating pea stems (Pisum sativum L.). The results obtained from dehydration and rehydration experiments will be compared to determine whether there is significant hysteresis in the pressure-volume relation for cells in pea stem tissue. Also, it is not known how Estat(P) compares with Einst(P). Investigations are proposed to determine Estat(P) and Einst(P) for the same cells and tissue, to elucidate the relationship between the two values.