Biosynthesis and excretion of hydrolases in germinating cereal seeds

摘要

The initial formation site of hydrolases in germinating cereal seeds and their subsequent release were examined using the substrate-film technique. Early in the germination of cereal seeds, e.g., barley, wheat, rye, oat and maize,α-amylase invariably appeared in the region of the epithelial cells of the scutellum, whereas it later gradually diffused into the entire region of the endosperm tissues. The initial formation site of proteinase and RNA-ase in germinating barley seeds was also confirmed to be in the epithelium. We conclude that the epithelium has a more important role in the enzymic breakdown of reserve substances stored in the endosperm tissues than the aleurone layer