Chemotaxonomic Differentiation of Pinus Species Based on n‐Alkane and Long‐Chain Alcohol Profiles of Needle Cuticular Waxes

Abstract n‐Alkane and long‐chain alcohol (LCOH) profiles of needle cuticular waxes of nine provenances of three Pinus species (P. taeda. P. pinaster and P. pinea) were determined and their chemotaxonomic importance was studied. n‐Alkanes concentrations were very low in all Pinus spp. A lack of ability of these compounds to differentiate Pinus spp. and their provenances was observed. LCOH concentrations were much higher, being nonacosan‐10‐ol (10‐C29‐OH) the most abundant one in all Pinus spp. Total LCOH concentrations varied (P<0.001) between Pinus spp. with P. taeda presenting the highest (P<0.05) value and P. pinea the lowest one. Differences in LCOH profiles were large (P<0.001) and allowed separation of Pinus spp. in the Principal Component Analysis (PCA). Although a noticeable separation of individuals was not observed. cluster analysis on LCOH concentrations allowed a clear distinction between species, indicating their potential to be used as chemotaxonomic markers to differentiate provenances of different Pinus spp.