Variability of volatiles in Pinus cembra L. within and between trees from a stand in the Salzburg Alps (Austria) as assessed by essential oil and SPME analysis

Pinus cembra L. is a coniferous European mountain range tree rich in oleoresins and essential oils. Twig tips with needles are the most common tree parts used to obtain essential oils. As the whole tree contains volatiles, the essential oil composition from different parts was studied, including twig tips with needles from the bottom, the top and the cone bearing branches, cones, twigs without needles from the lower and upper part of the crown as well as wood and bark from the trunk. The variability in essential oil composition between these plant parts and between individual trees has been studied using multivariate statistical analyses. α-Pinene was present in all samples, being highest in cones (49.3%) and lowest in sapwood (0.7%). Twig tips with needles from different parts of the crown had similar essential oil composition with α-pinene (43.9–48.3%), β-phellandrene (13.1–17.2%), β-pinene (6.6–9.3%), germacrene D (5.1–6.8%) and limonene (4.1–6.1%) as main compounds. Twig essential oils had usually more β-phellandrene (23.9–29.8%) than α-pinene (23.3–24.3%) and also appreciable amounts of β-pinene (13.5–15.1%) and limonene (11.9–17.9%). Cone essential oils contained mainly α-pinene, β-pinene (20.1%) and limonene (13.9%). The essential oils from wood and bark were rich in diterpenes as cembratrienol (4.9–21.4%), cembrene (4.8–14.3%) and methyl daniellate (2.7–6.8%). Sapwood distillates contained also notable amounts of alkane derivatives. Finally, the solvent free SPME technique has been employed to analyse the volatiles in the plant parts. For needles and cones the observed patterns were in good accordance with the compositions of the respective essential oils.