Abstract

Abstract

Buxus is an exotic genus introduced in Iberian Peninsula by glacial dynamics. This genus is characterized by evergreen shrubs having some distinctive features and a wide range of ecological characteristics, becoming economically important for ornamental purposes, medicinal uses and carpentry work. Although, it is widely distributed in all continents, there are only two species of Bruxus in Europe, Buxus sempervirens and Buxus balearica. The first one is extensively distributed in Central Europe, and in Portugal it is found in Trás-os-Montes in the valley of Sabor River and Tua. In turn, B. balearica has a distribution limited to the Balearean Island and south of Spain. These two species of Buxus can be found in different habitats in Iberian Peninsula according to their different features. The objective of the present study was to characterize and establish relevant aspects that contribute to distinguish the two species, and to determine the variations within the same species related to the adaptation to the environmental conditions of the regions where the plants were established. Analysing the leaves' features is indicative information about their performance and is crucial to understanding the functional ecology of the genus. To achieve this, a morpho-anatomical study was carried out using several samples of leaves collected in specific region of Iberian Peninsula. The eighteen sample populations of Buxus were subdividing into three groups distinguished according to the type of environmental conditions.This study includes the leaf anatomical analysis and morpho-anatomical aspects related to the way the leaves save water, in particular the quantification of cuticular waxes, stomatal density and leaf mass per unit area (LMA). The obtained results indicate morpho-anatomical differences between the species. B. balearica has bigger foliar area and higher LMA than B. sempervirens that has smaller leaves, lower LMA and lower thick leaves. Both species...