Essential oil composition variability among natural populations of Pinus mugo Turra in Kosovo

Pinus mugo Turra, is a native pine species in central and southern Europe, growing in high mountains area (altitudes 1.800-2.300 m.a.s.l.). In Kosovo, it is one of the native pines too, distributed in high altitudes in the Sharri Mountains and Albanian Alps Mountains. Its populations represent an important wealth of essential oil resources available, which make this species very important in terms of economic values. The chemical composition and yields of the essential oils of dwarf pine (Pinus mugo Turra) needles, twigs and cones from six wild populations in Kosovo were investigated with the aim to assess their natural variability. The identity of P. mugo was confirmed by morphology and DNA barcoding. Sixty-two compounds were identified representing 69-95 % of the total identified compounds. The yield ranged from 0.3-0.8 % v/w in needles, 1.0-2.4 % v/w in twigs and 0.1-0.5 % v/w in cones, depending on the origin of plant material and plant organs. α-Pinene (needles: 16.9-24.5 %; twigs: 4.5-8.8 %; cones: 3.1-5.6 %), β-pinene (needles: 1.5-5.4 %; twigs: 2.2-15.4 %; cones: 1.3-14.2 %), δ-3-carene (needles: 15.4-27.8 %; twigs: 24.0-51.6 %; cones: 10.5-31.5 %), limonene + β-phellandrene (needles: 1.9-5.9 %; twigs: 12.6-24.2 %; cones: 2.1-9.3 %), (E)-caryophyllene (needles: 4.4-8.9 %; twigs: 4.0-10.8 %; cones: 10.3-26.9 %) and germacrene D (needles: 4.0-8.3 %; twigs: 0.2-6.19 %; cones: 0.1-12.4 %) were the major components of the essential oil. Principal component analysis (PCA) and hierarchical cluster analyses (HCA) suggests that the population of P. mugo clustering is not related to their geographic location, but rather seemed to be linked to local selective forces acting on chemotype diversity. Low variability related to their geographic location has an economic importance since samples originating from different locations in Kosovo can treated with same standards.