The wax layer and its morphological variability in four European Salix species

摘要

The structure of the wax layer on leaves was analysed in four species of the genus Salix (S. alba, S. fragilis, S. triandra and S. pentandra). SEM observations showed that peculiar conical structures (named here ‘conicoids’) are present on the lower surface of the leaves in three species. In S. fragilis and S. triandra, conicoids are similar in size, whereas in S. alba, they are several times larger. In S. pentandra no such structures were found and the cuticle was covered only with an amorphous wax film. The observed differences between species can be used as identifying features in this group of plants. A comparison of conicoids on successive leaves on the shoot revealed differences and shed some light on the process of their formation.