[Morphogenesis and histochemical investigation of peltate glandular trichomes on Glycyrrhiza uralensis Fisch. leaves].

ABSTRACT

Anatomical and histochemical investigation of the glandular trichomes on the leaves of Glycyrrhiza uralensis Fisch.were carried out by using scanning electronic microscopy (SEM), Light microscopy and fluorescence microscopy. Two types of peltate glandular trichomes can be distinguished one occurred on the leaves abaxial and adaxial surface with a short stalk and the second on the calyx surface with a long stalk. Secretory trichomes started as outgrowth of epidermal cells, subsequent divisions gave rise to trichomes made up of a basal cell, stalk cells and a multicellular secretory head. The histochemical identification revealed that complex substance excreted by the secretory cells contained flavoniods, polysaccharides and lipophilic compounds. During the development of glandular trichomes, only mature trichomes with ten-celled secretory head or even more cells could be observed the flavonoids inside or in subcuticular space but before that stages the flavonoids were not found. The findings provided a scientific basis for understanding the flavonoids synthesis and biological function.