Agronomical and chemical characterisation of Thymbra capitata (L.) Cav. biotypes from Sicily, Italy.

In this study, the agronomical and chemical characterisation of 13 Sicilian biotypes of Thymbra capitata (L.) Cav., grown under the same agricultural and environmental condition, are reported. The main morpho-productive parameters and quali-quantitative profile of essential oils (EOs) were determined. The EOs were analysed by gas chromatography-flame ionisation detector and gas chromatography-mass spectrometry. Hierarchical cluster analysis and principal component analysis statistical methods were used to group biotypes according to the EOs chemical composition. The EO yield ranged between 4.6 and 8.1 (v/w). A total of 38 EO compounds have been identified. The compounds mostly represented were α-pinene, myrcene, α-terpinene, p-cymene, γ-terpinene, borneol, carvacrol and β-caryophyllene. In all biotypes, the carvacrol (67.4-79.5%) was the main compound, confirming that T. capitata is a carvacrol chemotype. The results showed that all Sicilian Thymbra biotypes have a good adaptation to the climatic conditions of the test environment.