Rigidity Control Mechanism by Turgor Pressure in Plants

Abstract

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 rigidity control mechanism by which turgor pressure of plants. We modeled a wild plant as a thin cylindrical cantilever 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 herbaceous plants cleverly support their own bodies by selecting particular mechanical and physical characteristics that would appear to be counter-productive from a superficial perspective.