Laboratory of Plant Ecology, Department of Plants and Crops, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, Gent, Belgium.
Plant Sciences Unit, Institute of Agricultural, Fisheries and Food Research (ILVO), Caritasstraat 39, Melle, Belgium.
Ann Bot. 2020 Sep 14;126(4):729-744. doi: 10.1093/aob/mcaa076.
Turgor pressure within a plant cell represents the key to the mechanistical descriptiion of plant growth, combining the effects of both water and carbon availability. The high level of spatio-temporal variation and diurnal dynamics in turgor pressure within a single plant make it a challenge to model these on the fine spatial scale required for functional-structural plant models (FSPMs). A conceptual model for turgor-driven growth in FSPMs has been established previously, but its practical use has not yet been explored.
A turgor-driven growth model was incorporated in a newly established FSPM for soybean. The FSPM simulates dynamics in photosynthesis, transpiration and turgor pressure in direct relation to plant growth. Comparisons of simulations with field data were used to evaluate the potential and shortcomings of the modelling approach.
Model simulations revealed the need to include an initial seed carbon contribution, a more realistic sink function, an estimation of respiration, and the distinction between osmotic and structural sugars, in order to achieve a realistic model of plant growth. However, differences between simulations and observations remained in individual organ growth patterns and under different environmental conditions. This exposed the need to further investigate the assumptions of developmental and environmental (in)sensitivity of the parameters, which represent physiological and biophysical organ properties in the model, in future research.
The model in its current form is primarily a diagnostic tool, to better understand and model the behaviour of water relations on the scale of individual plant organs throughout the plant life cycle. Potential future applications include its use as a phenotyping tool to capture differences in plant performance between genotypes and growing environments in terms of specific plant characteristics. Additionally, focused experiments can be used to further improve the model mechanisms to lead to better predictive FSPMs, including scenarios of water deficit.
植物细胞的膨压代表了将水和碳可用性的影响结合起来对植物生长进行机械描述的关键。在单个植物中，膨压具有高度的时空变化和日动态变化，因此很难在功能结构植物模型（FSPM）所需的精细空间尺度上对其进行建模。先前已经建立了用于 FSPM 中的膨压驱动生长的概念模型，但尚未探索其实际用途。
在新建立的大豆 FSPM 中加入了膨压驱动的生长模型。该 FSPM 模拟光合作用、蒸腾作用和膨压动态与植物生长直接相关。将模拟与田间数据进行比较，用于评估建模方法的潜力和缺点。
模型模拟表明，需要包括初始种子碳贡献、更现实的汇函数、呼吸作用的估计以及区分渗透和结构糖，以实现植物生长的现实模型。然而，在个别器官生长模式和不同环境条件下，模拟和观测之间仍然存在差异。这暴露了需要进一步研究模型中参数的发育和环境（不）敏感性假设，这些参数代表模型中生理和生物物理器官特性。
该模型目前主要是一种诊断工具，用于更好地理解和模拟整个植物生命周期中单个植物器官水关系的行为。未来的潜在应用包括将其用作表型工具，以根据特定植物特征捕获基因型和生长环境之间植物性能的差异。此外，可以进行重点实验，以进一步改进模型机制，从而导致更好的预测性 FSPM，包括水分亏缺情景。
