Chemotaxonomy ofJuniperus communis, J. sibiricaandJ. intermedia

The oil chemical composition was studied in several populations of Juniperus communis, J. sibirica (J. nana sensu Pignatti) and J. intermedia growing spontaneously in the northwestern Italian Alps. The oil of J. communis was characterized by high percentages of sabinene (32% to 47%) and low values of α-pinene (9% to 22%), whereas J. sibirica showed opposite values (respectively 0.3% to 25% and 9% to 46%). The oil chemical composition of J. intermedia showed intermediate values for both sabinene (28%) and α-pinene (20%) when compared to the other two taxa. The data obtained from GC/MS analyses of the oils were used to study the chemotaxonomic characters of the three taxa. Chemometrics included multivariate statistical analyses such as Principal Component Analysis (PCA), Cluster Analysis (CA) and Discriminant Analysis (DA). The results of this investigation indicated that most of the populations considered as J. intermedia showed a statistically significant different oil composition when compared to J. communis and J. sibirica. The taxonomic position of J. intermedia was also discussed.