Variation of needle volatiles in native populations of Pinus mugo – evidence from multivariate statistical analysis

Abstract

Pinus mugo Turra sensu stricto (dwarf mountain pine) is a species native to central and southern Europe, which performs a key role in subalpine areas by preventing avalanches and soil erosion. In this study, headspace extraction coupled with GC-MS/FID analyses was used to analyze diversity of needle volatiles in 10 natural populations of P. mugo s. str. growing in the Julian Alps, southern Carpathians and Balkan Peninsula. The multivariate statistical analyses revealed clear differentiation between Julian Alpine and southern Carpathian populations, supporting the hypothesis about existence of vicariant gene pools in these two European mountain chains. Although several earlier studies have pointed out heterogeneity of the Balkan populations, none of the investigated Balkan populations have shown the volatile pattern similar to the Carpathian group, as they all formed a common group with the Alpine population. AHC of bioclimatic data as well as regression analysis suggested that general volatile differentiation in P. mugo s. str. essentially does not represent an adaptive response to bioclimatic, orographic or geological conditions. Therefore, the described population groups might be provisionally considered as two P. mugo s. str. chemotypes. Our findings regarding volatile characters complement those obtained from morpho-anatomical, phytochemical and molecular data reported so far.