Genetic resources of Thymus vulgaris L. and T. vulgaris x T. Marschallianus Willd. in the Czech Republic

Two varieties of <em>Thymus vulgaris</em> L. (&acute;Krajov&yacute;&acute; and &acute;Winter&acute;) and three its hybrids with <em>T. Marschallianus</em> Will. (variety &acute;Mixta&acute; and two accessions of variety &acute;Lemona&acute;) were evaluated according the Draft Descriptor List <em>Thymus vulgaris</em> L. and analysed for the essential oil content and composition in years 2014 and 2015. All evaluated accessions were found morphologically and/or chemically different. Varieties &acute;Krajov&yacute;&acute;, &acute;Winter&acute; and &acute;Mixta&acute; were assessed as a thymol type with the thymol (39.1 &ndash; 69.6 %), o-cymene (6.3 &ndash; 24.9 %) and &gamma;-terpinene (2.75 &ndash; 13.8 %) as main oil components. The two accessions of &acute;Lemona&acute; variety were found significantly different each other: one of them (income No. 3239) was assessed as a terpineol type with the terpineol acetate (75.7 %) and &alpha;-terpineol (16.9 %) as main oil components and the other one (income No. 2757) as a geraniol type with the geranyl acetate (&plusmn;42.4 %) and geraniol (&plusmn;20.8 %) as main oil components. Only the accession with income No. 3239 was proved as a &acute;Lemona&acute; variety due its citral (&plusmn;9.3 %) content, though even this content is too small compare to original &acute;Lemona&acute; where about 20 % of citral was declared.