infrastructure, development and histochemistry of the polysaccharide-containing subcuticular compartments in Origanum dictamnus L. peltate glandular hairs

摘要

Peltate glandular hairs of Origanum dictamnus at the stage of secretion create two subcuticular chambers; one large and bladder-like, at the apex of the head (containing essential oil), and one small and ring-like, at the bottom of the head (containing polysaccharides). In the apical chamber, along with the essential oil, a small lateral compartment containing polysaccharides, also exists. This compartment surrounds peripherally the apical chamber creating a second ring-like structure. The apical plasmalemma of the head cells exhibits a high electron density and presumably has a specific substructure to facilitate passing to the subcuticular chamber of the secretory product. The latter probably exists in the form of glucosides, which, after passing across the plasmalemma and entering the apical chamber, become hydrolysed into the aglycone fraction (essential oil) and the sugar fraction (polysaccharides).