Source-sink partitioning. Do we need Munch?
Source-sink partitioning. Do we need Munch?
复制标题
DOI：
10.1093/jxb/erf037
复制
发表时间：
2002-09-01
影响因子：
6.9
通讯作者：
Soltani, F
中科院分区：
文献类型：
--
作者：
Bancal, P;Soltani, F
由Munch理论模拟韧皮部的运输通常使用从源到汇的阻力：因此，阻力被认为是分配中的重要因素。虽然阻力通常是一个设定的常数，但实际上它受到粘度的强烈影响，因此受到输送溶质浓度的强烈影响。本文首先对Minchin等人提出的分配模型进行了粘度变化修正。该模型被进一步修改，与源被认为是一个活动的溶质生产，而不是作为一个室浓度。如果这样定义，源就不能不同于汇活动的总和，这在很大程度上已经过时了限制源或汇的概念。修正后的模型将阻力对分配的影响局限于低源活动。在所分析的小麦籽粒灌浆的例子中，这种活动是如此之低，以至于它们只对应于病理条件。在这种情况下，在建模中使用抗性因此只是一个数学负担，甚至不容易量化，因为它们与难以获得的解剖特征相关。不考虑阻力，直接从源活动计算汇活动变得容易，使用直观，易于访问的参数化。这种简化的条件进行了讨论。
The simulation of phloem translocation by the Munch theory commonly uses resistances from sources to sinks: the resistances are therefore regarded as important in partitioning. Although resistance is generally a set constant, it is in fact strongly affected by viscosity, and thus the concentration of the transported solute. In this paper, the model of partitioning proposed by Minchin et al. was first corrected for variations in viscosity. The model was further modified, with the source considered as an activity of solute production rather than as a compartment concentration. When so defined, the source cannot differ from the sum of sink activities, largely outdating the source- or sink-limitation concepts. The corrected model confined the effect of resistances on the partitioning to low source activities. In the example of wheat grain filling analysed, such activities would be so low that they would correspond only to pathological conditions. In that case, the use of resistances in modelling is therefore just a mathematical burden, not even easily quantifiable since they are related to anatomical traits that are difficult to access. Leaving out resistances, it becomes easy to calculate the sink activities directly from the source activities, using an intuitive, accessible parametrization. The conditions for such a simplification are discussed.