Growth-sustaining Water Potential Distributions in the Primary Corn Root: A NONCOMPARTMENTED CONTINUUM MODEL.
Growth-sustaining Water Potential Distributions in the Primary Corn Root: A NONCOMPARTMENTED CONTINUUM MODEL.
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玉米主根中维持生长的水势分布：非配室连续模型。
DOI：
10.1104/pp.66.5.859
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发表时间：
1980
期刊：
影响因子：
7.4
通讯作者：
K. K. Wagner
中科院分区：
文献类型：
--
作者：
W. Silk;K. K. Wagner
一个方程是从运输理论中推导出来的，它将局部增长率与扩张组织中的局部水势联系起来。对于无隔室连续介质模型，元素的相对生长速率（L）等于渗透系数（K）与水势梯度（psi）的张量积的散度，即L = big dn tri，open * [K]。大DN三，开放PSI]。利用已发表的L和K值对该方程进行数值求解，以显示能够维持所观察到的玉米初生根生长模式的水势分布。维持生长所需的水势从根的外部到内部逐渐减小，并且纵向剖面在最高生长速率的位置附近显示出最大的负值。一个细胞最初位于顶点附近的经验损失，然后在水势的增益，因为它是通过生长区的位移。该方法从以前的公式在两个方面：生长速率的空间异质性的假设，和解决方案的空间（特定地点），而不是材料（细胞特定）的水势值。空气空间的作用和组件（壁和可能的细胞质）的水传导途径，不积累水仍然有待澄清，而且，在早期的工作中，最不确定的方面的分析可能是水力传导率的值。
An equation is derived from transport theory to relate local growth rate to local water potential in an expanding tissue. For a noncompartmented continuum model, the relative elemental growth rate (L) equals the divergence of the tensor product of hydraulic conductivity (K) and the gradient of water potential, psi, i.e. L = big dn tri, open * [K . big dn tri, open psi]. This equation is solved numerically using published values of L and K to show the water potential distribution which can sustain the observed growth pattern in the primary root of Zea mays L. The water potential required to sustain growth decreases from the outside to the inside of the root, and the longitudinal profile shows most negative values near the location of the highest growth rate. A cell originally located near the apex experiences a loss and then a gain in water potential as it is displaced through the growth zone.THE APPROACH DIFFERS FROM PREVIOUS FORMULATIONS IN TWO RESPECTS: the assumption of spatial heterogeneity in growth rate, and the solution for spatial (site-specific) rather than material (cell-specific) values of water potential. The role of air spaces and of components (wall and possibly cytoplasm) of the water-conducting pathway which do not accumulate water remains to be clarified; and, as in earlier work, the most uncertain aspects of the analysis are probably the values for hydraulic conductivity.