Grass seeds include the coleoptile (shoot sheath), the scutellum, the radicula and the coleorrhiza (root sheath) (Figure1.1). The scutellum is homologous to the leaf lamina of the cotyledon and the coleoptile to the leaf sheath of the cotyledon. Co-leoptile and coleorrhiza are membranes that protect shoot and leaf meristems and the radicula, respectively, during the first step of the germinatio…