Dissertation committee:
Σοφία Ριζοπούλου Αν. Καθηγήτρια (Επιβλέπουσα), Μαρία-Σόνια Μελετίου-Χρήστου Λέκτορας, Κώστας Φωτάκης Καθηγητής
Summary:
Interesting properties have been discovered on the surfaces of plant tissues
(hydrophobic, hydrophilic) that contribute to the ability of plants to cope
with conditions in the abiotic and biotic environment of their habitats. These
properties are related to the microsculpture of the surfaces as well as their
chemistry. The existence of micro- and nano- structures on the surfaces of
leaves, which constitute the boundary of plants with their environment, is
related to the constant stress brought on by environmental conditions,
resulting in the development of adaptive mechanisms by plants through natural
selection. The aim of this thesis was the study of the water status of leaf
surfaces of Mediterranean plant species, in comparison with a few exotic
species, and the overall characterization of the water status and the surfaces
in relation to their wettability. The adaxial and abaxial leaf surfaces of 14
species were observed using scanning electron microscopy, before and after the
removal of epicuticular waxes. Contact angle, hysteresis, sliding angle,
surface free energy and water retention were then estimated for each surface.
Finally, fatty acid analysis of the waxes removed from leaf surfaces, as well
as of the total lipid content of leaves was performed with gas chromatography.
Keywords:
Plant leaves, Hydrophobic surface, Wettability, Fatty acids, Surface energy