what is cuticle in plants

The plant cuticle is a protective film covering the outermost skin layer (epidermis) of leaves, young shoots, and other aerial plant organs. It is composed of lipid and hydrocarbon polymers infused with wax, and is synthesized by the epidermal cells of the plant. The primary function of the plant cuticle is to act as a water permeability barrier, preventing evaporation of water from the epidermal surface and also preventing external water and solutes from entering the tissues. Additionally, the cuticle protects plants against drought, extreme temperatures, UV radiation, chemical attack, mechanical injuries, and pathogen/pest infection. It also provides mechanical support and serves as a barrier against organ fusion. The cuticle is an essential component for the overall health and quality of the plant, as it defends against environmental forces and stress, and decreases susceptibility to various threats such as fungi, pathogens, and pests. The cuticle is made up of two separate layers: the first layer is comprised of cutin, a variety of waxy polymers embedded with polysaccharides, while the second layer is made of hydrophobic cuticular waxes instrumental in the plant’s permeability to water.