seedcoat
The seed coat, or testa, is the protective outer layer of a seed. It develops from the integuments of the ovule after fertilization and encloses the embryo and, in many seeds, the endosperm. In angiosperms the coat often comprises an outer epidermal layer (exotesta) and an inner layer (endotesta) that may be lignified or sclerenchymatous; some seeds have a simpler, thinner coating or multiple parenchymatous layers. Pigments, suberin, lignin, and tannins can give the coat color, hardness, and drought resistance.
The seed coat serves several functions. It provides mechanical protection against damage and pathogens and helps
Variation exists across plant groups. The seed coat is derived from the ovule’s integuments in both gymnosperms