Graduate School of Engineering, Hokkaido University, Kita 13, Nishi 8, Kita-ku, Sapporo, 060-8628, Japan.
Department of Mechanical Engineering, Faculty of Systems Science and Technology, Akita Prefectural University, 84-4 Yurihonjo, Akita, 015-0055, Japan.
Sci Rep. 2023 Feb 4;13(1):2063. doi: 10.1038/s41598-023-29294-5.
The bodies of herbaceous plants are slender, thin, and soft. These plants support their bodies through the action of turgor pressure associated with their internal water stores. The purpose of this study was to apply the principles of structural mechanics to clarify the underlying mechanism of rigidity control that is responsible for turgor pressure in plants and the reason behind the self-supporting ability of herbaceous plants. We modeled a plant a horizontally oriented thin-walled cylindrical cantilever with closed ends enclosing a cavity filled with water that is acted on by its own weight and by internal tension generated through turgor pressure. We derived an equation describing the plant's consequent deflection, introducing a dimensionless parameter to express the decrease in deflection associated with the action of turgor pressure. We found that the mechanical and physical characteristics of herbaceous plants that would appear to be counter-productive from a superficial perspective increase the deflection decreasing effect of turgor pressure.
草本植物的躯体细长、单薄且柔软。这些植物通过内部储水所产生的膨压作用来支撑其躯体。本研究旨在应用结构力学原理来阐明植物刚性控制的内在机制，该机制负责控制膨压，并解释草本植物自支撑能力的原理。我们将一株植物建模为一个水平放置的薄壁圆柱形悬臂，其两端封闭，内部有空腔，其中充满水，水会受到自身重量和由膨压产生的内部张力的作用。我们推导出了一个描述植物后续挠度的方程，引入了一个无量纲参数来表示与膨压作用相关的挠度减小。我们发现，从表面上看，草本植物的力学和物理特性似乎会产生适得其反的效果，而实际上这些特性增加了膨压的挠度减小效果。
