Montpellier SupAgro, Département Sciences du Végétal, France.
Ann Bot. 2011 Apr;107(5):729-45. doi: 10.1093/aob/mcq173. Epub 2010 Sep 18.
There is increasing interest in the development of plant growth models representing the complex system of interactions between the different determinants of plant development. These approaches are particularly relevant for grapevine organogenesis, which is a highly plastic process dependent on temperature, solar radiation, soil water deficit and trophic competition.
The extent to which three plant growth models were able to deal with the observed plasticity of axis organogenesis was assessed. In the first model, axis organogenesis was dependent solely on temperature, through thermal time. In the second model, axis organogenesis was modelled through functional relationships linking meristem activity and trophic competition. In the last model, the rate of phytomer appearence on each axis was modelled as a function of both the trophic status of the plant and the direct effect of soil water content on potential meristem activity.
The model including relationships between trophic competition and meristem behaviour involved a decrease in the root mean squared error (RMSE) for the simulations of organogenesis by a factor nine compared with the thermal time-based model. Compared with the model in which axis organogenesis was driven only by trophic competition, the implementation of relationships between water deficit and meristem behaviour improved organogenesis simulation results, resulting in a three times divided RMSE. The resulting model can be seen as a first attempt to build a comprehensive complete plant growth model simulating the development of the whole plant in fluctuating conditions of temperature, solar radiation and soil water content.
We propose a new hypothesis concerning the effects of the different determinants of axis organogenesis. The rate of phytomer appearance according to thermal time was strongly affected by the plant trophic status and soil water deficit. Furthermore, the decrease in meristem activity when soil water is depleted does not result from source/sink imbalances.
人们越来越关注开发能够代表植物发育不同决定因素之间复杂相互作用的植物生长模型。这些方法对于葡萄器官发生特别重要，因为器官发生是一个高度可塑的过程，取决于温度、太阳辐射、土壤水分亏缺和营养竞争。
评估了三个植物生长模型在处理观察到的轴器官发生可塑性方面的程度。在第一个模型中，轴器官发生仅通过热时间取决于温度。在第二个模型中，通过将分生组织活性与营养竞争联系起来的功能关系来模拟轴器官发生。在最后一个模型中，每个轴上出现的拟叶体的速度被建模为植物的营养状态和土壤水分含量对潜在分生组织活性的直接影响的函数。
包含营养竞争和分生组织行为之间关系的模型，与基于热时间的模型相比，模拟器官发生的均方根误差（RMSE）减少了九倍。与仅由营养竞争驱动轴器官发生的模型相比，实施水分亏缺与分生组织行为之间的关系改善了器官发生模拟结果，导致 RMSE 减少了三倍。由此产生的模型可以被视为首次尝试建立一个全面的完整植物生长模型，模拟在温度、太阳辐射和土壤水分含量波动条件下整个植物的发育。
我们提出了一个关于影响轴器官发生的不同决定因素的新假设。根据热时间出现拟叶体的速度受到植物营养状态和土壤水分亏缺的强烈影响。此外，土壤水分耗尽时分生组织活性的降低并不是源/汇失衡的结果。
