The Relation of Tannins to the Differentiation of the Root Tissues in Reaumuria palaestina

Abstract

Tannins are produced and accumulated in cells of the epidermis, the inner layers of the cortex, and the outer layers of the root cap of seminal roots of Reaumuria palaestina Boiss. Tannins are found in promeristem cells in cisternae bounded by single membranes that look like the endoplasmic reticulum. These cisternae inflate, coalesce, and form the central vacuole as the tissues differentiate. The relation between tannin cisternae and the endoplasmic reticulum is not entirely clear.