Caracterización morfo-anatomía y aceites esenciales de Tagetes terniflora y Tagetes minuta (Asteraceae) de Tucumán (Argentina).

The essential oil composition and morpho-anatomy of Tagetes minuta, collected at “El Mollar” and two different populations of Tagetes terniflora collected in Tafi del Valle (Tucuman, Argentina) were studied. The essential oil of aerial parts (flowers and leaves) from both species was analyzed by gas chromatography-mass spectrometry. Qualitative and quantitative differences were observed in the composition of the essential oil from both species. Oxygenated monoterpenes were the dominant compounds in the essential oil from both collections of T. terniflora where the main component was cis-tagetone (33.6% and 58.4% respectively) accompanied by significant amounts of the monotepene hydrocarbon cis-?-ocimene (17.1% and 17.4% respectively). cis-Tagetone (53.2%) was also a dominant component in T. minuta along with dihydrotagetone (10.4%) and cis-?-ocimene (19.9%). cis- and transocimenone were distinctive components of T. terniflora which were not detected in T. minuta. Anatomically stands out the presence of secretory cavities and glandular trichomes in foliar blades and secretory ducts in stems and petiole of both species.