Chemical Composition and Water Permeability of Fruit and Leaf Cuticles of Olea europaea L.

The plant cuticle, protecting against uncontrolled water loss, covers olive (Olea europaea) fruits and leaves. The present study describes the organ-specific chemical composition of the cuticular waxes and the cutin and compares three developmental stages of fruits (green, turning, and black) with the leaf surface. Numerous organ-specific differences, such as the total coverage of cutin monomeric components (1034.4 μg cm-2 and 630.5 μg cm-2) and the cuticular waxes (201.6 μg cm-2 and 320.4 μg cm-2) among all three fruit stages and leaves, respectively, were detected. Water permeability as the main cuticular function was 5-fold lower in adaxial leaf cuticles (2.1 × 10-5 m s-1) in comparison to all three fruit stages (9.5 × 10-5 m s-1). The three fruit developmental stages have the same cuticular water permeability. It is hypothesized that a higher weighted average chain length of the acyclic cuticular components leads to a considerably lower permeability of the leaf as compared to the fruit cuticle.