Terpene composition variations in diverse provenances of Cedrus libani (A.) Rich. and Cedrus atlantica Manet

Mono- and sesquiterpenes are good markers for distinguishing conifer species one from another, and provenances of the same species. In the genus Cedrus, the identification of C. libani requires C. libani to be distinguished from the main provenances of C. atlantica; two provenances of C. libani were recognized. Consequently it was decided to look for terpene markers among samples from six provenances of these two species. Longifolene appears as a specific marker of C. libani Pozanti; C. libani Barouk is less easy to identify by the presence of bornyl acetate, because one out of three analysed individuals does not contain it. Factorial Discriminant Analysis underlines the differences between C. atlantica and C. libani, according to one axis (β-myrcene/α- and β-pinene). The second axis allows Barouk and Pozanti provenances of C. libani to be distinguished by their limonene and β-pinene contents. In C. atlantica, the same procedure allows Algerian and Moroccan provenances to be separated. The Mann-Whitney test confirms that C. libani Pozanti is always specified by the lowest values of β-myrcene. Similarly, C. libani Barouk′s high β-pinene content differentiates it from various provenances of C. atlantica, except in the case of some individuals (Talassentane provenance). So, C. libani Pozanti is always easier to identify than C. libani Barouk.