The plant cuticle: formation and structure of epidermal surfaces

Epicuticular wax crystals cause diffuse light scattering, giving respective plant surfaces a whitish appearance, while smooth surfaces, devoid of crystals, are shiny. All land plants are coated with a waxy cuticle that is essential for their protection and interaction with the environment. The main functions of the cuticle are to limit non-stomatal water loss and to repel water on the surface of the plant, minimizing deposition of dust, pollen and air pollutants. The continuity of the cuticle is maintained during division, differentiation and expansion of individual epidermal cell types. In the near future, similar information will be available from other plant species, and should greatly contribute to our overall understanding of the diversity of plant cuticles. Scanning electron micrographs depict the typical shape of crystals on an exemplary plant species. Scanning electron microscopy surveys of various plants reveal an enormous diversity in the shape, size and arrangement of three-dimensional structures protruding from the cuticle surface.