Variability of the needle essential oils of Pinus peuce from different populations in Montenegro and Serbia.

The essential-oil composition of Pinus peuce Griseb. is reported at the population level. Macedonian pine is endemic high-mountain Balkan pine relict of an anthropogenically reduced area, with large morphological diversity and insufficiently clear taxonomic position. In the pine-needle terpene profile of two populations from Montenegro and one from Serbia, 78 compounds were detected, 56 of which are identified (Table 3). The dominant constituents were alpha-pinene (36.5%) and germacrene D (11.4%). The following 20 additional components were found to be present in medium-to-high amounts (0.5-10%): camphene (8.5%), bornyl acetate (6.8%), beta-pinene (6.8%), beta-caryophyllene (5.2%), beta-phellandrene (4.7%), terpinen-4-ol acetate (1.6%), (E)-hex-2-enal (1.5%), alpha-muurolene (1.2%), beta-gurjunene (1.1%), beta-myrcene (1.0%), alpha-terpinyl acetate (0.9%), alpha-phellandrene (0.8%), delta-cadinene (0.8%), alpha-humulene (0.8%), sabinene (0.7%), aromadendrene (0.6%), alpha-thujene (0.6%), gamma-muurolene (0.6%), gamma-cadinene (0.6%), alpha-terpinolene (0.5%), and one unknown component (0.5%). The similarity of the populations and the within-population variability were visualized by principle-component analysis (PCA) and genetic analysis of selected terpenes in 90 tree samples. Our study suggests a closer connection between populations II and III compared to population I. Based on the profile of the main terpene components, the studied populations are more similar to populations from Kosovo and Greece than to the population from Mt. Mokra (Montenegro) and the population in France.