Leaf epidermal characteristics and genetic variability in Central European populations of broad-leaved Festuca L. taxa

Abstract

Leaf epidermal (micromorphological and micromorphometric) features of the leaf blade were examined with light and scanning electron microscopy in 49 Central European natural populations of species belonging to subgenera Schedonorus and Drymanthele within the genus Festuca L. In addition, molecular biological (random amplified polymorphic DNA) studies were conducted on selected populations. The goal of the study was to reveal the degree of anatomical and genetic variability at the taxon and population level, as well as to determine the most important characters that allow differentiation of the taxa in these two subgenera. The anatomical variation was compared with the genetic distance between taxa. Investigated taxa exhibited great anatomic variability in terms of both qualitative (presence or absence, shape and appearance of various cell types) and quantitative characters (frequency and size of cells). Strong correlation was found between the genetic distance of populations and the frequency and size of silica cells in the costal zone of the epidermis, which indicates that silica cells are largely determined by the genetic background, regardless of varying environmental conditions. Our studies highlight that despite the high level of variability in anatomical features and genetic polymorphism, these fescue populations clearly segregate both in terms of epidermal structure and genetic constitution.