Chemodiversity of Epicuticular n-Alkanes and Morphological Traits of Natural Populations of Satureja subspicata Bartl. ex Vis. along Dinaric Alps - Ecological and Taxonomic Aspects

Abstract

Morphological characters and the composition of epicuticular leaf n-alkanes of two Satureja subspicata Bartl. ex Vis. subspecies (subsp. liburnica Sili and subsp. subspicata) from nine natural populations along Dinaric Alps range were studied. Morphological characters were chosen based on Silis subspecies separation. Seventeen n-alkane homologues (C-19 - C-35) were identified using gas chromatography/mass spectrometry (GC/MS) and GC/flame ionisation detector (FID). The most abundant n-alkane in all populations was n-nonacosane (C-29), followed by n-hentriacontane (C-31), with the exception of Divaa population where these two alkanes were co-dominant. Diversity and variability of n-alkane patterns and morphological characters and their relation to different geographic and bioclimatic parameters, including exposure, were analysed by several statistical multivariate methods (PCA, HCA, Discriminant Analysis, Mantel test). These tests showed clear separation of subsp. liburnica from subsp. subspicata, even though population Velebit showed separation from other subsp. liburnica populations based on phytochemical characters. Mantel test showed high correlation with geographical distribution in both investigated data sets. High correlation between morphological and phytochemical characters was also established. However, exposure can influence n-alkane profile, suggesting precaution while taking samples from natural habitats.