Epicuticular Wax Composition of Leaves of Tilia L. Trees as a Marker of Adaptation to the Climatic Conditions of the Steppe Dnieper

The relationship between the adaptive ability of different linden genotypes to the changing climatic conditions of the Steppe Dnieper and the epicuticular wax component composition of tree leaves was investigated. Specificity of the epicuticular wax hydrocarbon composition of linden autochthonous species (T. cordata) and introduced species (T. platyphyllos and T. begoniifolia) was established. For all genotypes, significant differences in the composition of epicuticular waxes from the surface of shaded and sun-adapted leaves were identified. The greatest accumulation of the epicuticular waxes was on the leaves of T. platyphyllos both under the shading conditions and illumination (11.0 and 17.6 μg/cm2, respectively). The general pattern for the genus Tilia L. species consisted in a substantial increase in the content of very long-chain n-alkanes simultaneously with a sharp decrease in the free fatty acid content in the composition of epicuticular waxes under the intensive illumination of leaves.