Population Diversity of n–Alkanes in the Needle Cuticular Wax of Relicts Pinus heldreichii and P. peuce from the Scardo-Pindic Mountains

The variability of n-alkanes in the needle cuticular wax of Pinus heldreichii and P. peuce in two natural populations from the Scardo-Pindic mountains was investigated for the first time. Gas chromatography (GC) and gas chromatography/mass spectrometry (GC–MS) analyses of two-year-old needles were performed using an Agilent 7890A GC equipped with an inert 5975C XL EI/CI mass spectrometer detector (MSD) and a flame ionization detector (FID) connected by a capillary flow technology 2-way splitter with make-up. An HP-5MS capillary column was used. n-Alkanes ranged from C19 to C33. In P. heldreichii the most abundant were C23, C25 and C27 (16.3, 15.6 and 12.8% on average, respectively), while in P. peuce they were C29, C25, and C27 (16.5, 15.3 and 13.5% on average, resp.). Mid-chain and long-chain n-alkanes prevailed in both species. Principle component analysis (PCA) and Cluster analyses of five and six n-alkanes, respectively, showed divergence of the Scardo-Pindic populations from the Dinaric ones.