MICROMORPHOLOGY OF THE LEAF EPIDERMIS SURFACE IN SOME PYRINAE SPECIES (ROSACEAE)

Abstract

Scanning electron microscopy (cryoSEM) was used to study the micromorphology of the leaf epidermis surface of species of 6 genera: Sorbus L., Aronia Medik., Amelanchier Medik., Cydonia Mill., Cotoneaster Medik., Crataegus L. (Rosaceae). The surface of the leaves of the studied plants has two types of cuticular folding. In C. melanocarpus and S. aucuparia, larger and sometimes branched single cuticular strands, usually located on one cell, were observed. In other species, the folding has the form of numerous smaller parallel microstrands running along the long axis of the cell. Different degree of manifestation of both types of cuticular folding was observed on the surface of main epidermal cells on one or both sides of the leaf blades. In addition, the stomata and trichomes were surrounded by radial striations. Microstrands in A. spicata and S. aucuparia were also present on papillae in the area of stomata. All the studied species show stomatal dimorphism. Larger primary stomata with more pronounced cuticular strands are located at some distance or in the center of a group of several smaller secondary stomata. The proportion of primary stomata ranged from 5 to 17%. In the studied species, there is a negative correlation between the stomata length and stomata density, which is close to such correlation in other taxa.