Chemotaxonomic study on Thymus xtoletanus Ladero and its parental species

We analysed the essential oils of cultivated material of Thymus xtoletanus Ladero and its parents, Th. mastichina (L.) L. and Th. villosus subsp. lusitanicus (Boiss.) Coutinho, with seeds from the same locality in the centre of the Iberian Peninsula. The essential oil of Th. xtoletanus, which had not been analyzed previously, presented 1,8-cineole as the major component (25.5%), as was also the case for Th. mastichina (76.1%). Other components with a major presence in Th. xtoletanus and Th. villosus subsp. lusitanicus were [(Z)-β-ocimene (8.1%); camphor (4.5%); sabinene (3.2%); α-pinene (2.8%)], and [(Z)-β-ocimene (4.1%), camphor (9.8%), sabinene (2.8%), α-pinene (7.1%)], respectively. However, in the hybrid the components β-phelandrene (14.5%), limonene (6.9%), (E)-γ-bisabolene (3.5%), and viridiflorol (3.3%) stood out, inter alia, whereas their presence in the parents was limited. The study confirms the hybrid origin of Th. xtoletanus as intermediate between Th. mastichina and Th. villosus subsp. lusitanicus.