Chemotaxonomic Evaluation by Volatolomics Analysis of Fifty-Two Genotypes of Myrtus communis L.

A population of 52 genotypes of Myrtle (Myrtus communis L.), selected in the framework of a domestication program and growing in the same collection field at Oristano (Central Western Sardinia, 39°54′ N 8°35′ E), was analyzed by GC/MS for leaf essential oil composition. The chemical composition of essential oils was quite variable with a number of compounds ranging from 31 to 78 depending on cultivar. One hundred and eighteen compounds were globally identified in the various genotypes. However, α-pinene, limonene, 1,8-cineole, α-terpineol, and linalool always resulted as main components with few differences among samples. Minor compounds have been the determining factors in differentiating or associating genotypes in the outputs of a principal component analysis (PCA), where the results of another analysis of fruit essential oils of the same genotypes were also jointly used. Genotypes were discriminated according to mother plant characterization or ecological variables, such as site altitude, soil nature, and presence or absence of calcareous soils in the substrate of the localities of origin.