Cuticular Wax Variability of A. alba, A.xborisii-regis and A. cephalonica from the Balkans: Chemophenetic and Ecological Aspects

This is the first study on cuticular wax variability of Abies alba, A.xborisii-regis and A. cephalonica, using 18 native populations from the assumed hybrid zone in the Balkan Peninsula. Presence of 13 n-alkanes with chain-lengths ranging from C-21 to C-33, one primary alcohol, two diterpenes, one triterpene and one sterol was determined in hexane extracts of 269 needle samples. The multivariate statistical analyses at the population level entirely failed in supporting circumscription of Balkan Abies taxa and therefore, in identifying hybrid populations. However, performed at the species level, these analyses revealed a certain tendency of differentiation between A. alba and A. cephalonica, while individuals of A.xborisii-regis were largely overlapped by the clouds of both parent species. Finally, the correlation analysis suggested that the observed variation of wax compounds was probably genetically conditioned and that it does not represent an adaptive response to various environmental factors.