Revisiting plant cuticle biophysics

The plant cuticle is located at the interface of the plant with the environment, thus acting as a protective barrier against biotic and abiotic external stress factors, and regulating water loss. Additionally, it modulates mechanical stresses derived from internal tissues and also from the environment. Recent advances in the understanding of the hydric, mechanical, thermal, and, to a lower extent, optical and electric properties of the cuticle, as well as their phenomenological connections and relationships are reviewed. An equilibrium based on the interaction among the different biophysical properties is essential to ensure plant growth and development. The notable variability reported in cuticle geometry, surface topography, and microchemistry affects the analysis of some biophysical properties of the cuticle. This review aimed to provide an updated view of the plant cuticle, understood as a modification of the cell wall, in order to establish the state-of-the-art biophysics of the plant cuticle, and to serve as an inspiration for future research in the field.