Forest Loïc, Padilla Fernando, Martínez Salomé, Demongeot Jacques, San Martín Jaime
Laboratoire Techniques de l'Imagerie, de la Modélisation et de la Cognition (TIMC UMR CNRS 5525), Institut d'Ingénierie de l'Information de Santé, Pavillon Taillefer, Faculté de Médecine, 38706 La Tronche cedex, France.
J Theor Biol. 2006 Jul 21;241(2):241-51. doi: 10.1016/j.jtbi.2005.11.029. Epub 2006 Jan 5.
When a tree stem deviates from verticality, as a result of different environmental factors, patterns of differential radial growth appear. Higher rates of wood production have been observed on the lower side of the tree and lower rates in the opposite side. Biological studies on plant hormones have shown that the concentration of auxin induces radial growth. They also have demonstrated the redistribution of auxin transport in response to gravity. Auxin is then designated as a mediator for differential growth. This paper presents a model for three-dimensional (3-D) auxin transport in conifer trees, which includes gravity dependence. We obtain realistic heterogeneous patterns of auxin distribution over the tree. Then, we propose a law of growth based on auxin concentration to simulate successive differential radial growths. The predicted growths are compared with experimental results of reconstruction of 3-D annual growth of Radiata pine.
当树干由于不同环境因素偏离垂直方向时，会出现径向生长差异的模式。在树的下侧观察到较高的木材生长速率，而在相对的一侧则较低。关于植物激素的生物学研究表明，生长素的浓度会诱导径向生长。他们还证明了生长素运输会因重力而重新分布。因此，生长素被指定为差异生长的介质。本文提出了一个包含重力依赖性的针叶树三维生长素运输模型。我们获得了树木上生长素分布的真实异质模式。然后，我们提出了一种基于生长素浓度的生长规律，以模拟连续的差异径向生长。将预测的生长情况与辐射松三维年轮生长重建的实验结果进行了比较。
