Diversity of needle n-alkanes, primary alcohols and diterpenes in Balkan and Carpathian native populations of Pinus nigra J.F. Arnold

Abstract

This is the first report on population differentiation based on composition of three different compound classes (n-alkanes, primary alcohols and diterpenes) in the epicuticular waxes of European black pine (Pinus nigra) from Balkan Peninsula and Southern Carpathians. The n-hexane extracts of 263 samples, originating from 15 native populations of four P. nigra subspecies (nigra, dalmatica, banatica and pallasiana), were investigated by GC-MS and GC-FID analyses. In all studied populations n-alkanes represent the most abundant compound group, while the contents of diterpenes and alcohols were lower and variable. Multivariate statistical analyses (Canonical Discriminant Analysis and Agglomerative Hierarchical Clustering) suggest existence of two clearly differentiated chemical entities with the basic difference in the content of primary alcohols (especially cis-9-octadecen-1-ol and 1-hexadecanol). The first group (low alcohol content) included all populations of ssp. nigra, ssp. dalmatica and ssp. banatica, as well as the two northernmost populations of ssp. pallasiana from Serbia and Bulgaria, while the second group (high alcohol content) comprised individuals from Greek and Macedonian populations of ssp. pallasiana. According to the recently proposed concept of ancient split of major genetic lineages of P. nigra, both chemical entities detected in this study belong to the same (Balkan Peninsula) genetic group. Taxonomic implications of given results are briefly discussed in relation with previous data based on morphological and molecular characters.