Yarrow (Achillea millefolium L.) Growth at Different Altitudes in Central Italian Alps: Biomass Yield, Oil Content and Quality

ABSTRACT

Achillea millefolium L. (yarrow) is a perennial herb, native to Europe and Asia and growing wild at different environmental conditions (altitude, soil). Since ancient ages, yarrow leaves and flowers have been used as medicinals, in cosmetics, and food industries. Plant height, number of inflorescences, fresh biomass and essential oil content, yield and composition of Achillea millefolium L. grown at different altitudes (from 250 m to 1,100 m) were studied. Plant height (from 54 cm to 77 cm) and essential oil content per plant (from 0.16% to 0.22%) were not significantly affected by environment, while the number of inflorescences/plant, fresh biomass herb yield (from 5 Mt/ha to 12 Mt/ha) and essential oil yield (from 1.12 Kg/ha to 2.51 Kg/ha) were significantly influenced by environment.

As far as the composition of essential oils is concerned, there was a remarkable change in some monoterpenes and sesquiterpenes: in particular α- and β-thujone were not present in oils from fields at a higher altitude, suggesting that their synthesis depends on both genetic and environmental factors. The concentrations of lavandulyl acetate, chama-zulene, P-caryophyllene, a-humulene and y-curcumene + germacrene D are greatly influenced by environmental growing conditions. From a qualitative point of view, essential oils from different environmental condition have different characteristics.

KEYWORDS:

• α-Thujone
• β-thujone
• cultivation
• environmental influence
• essential oil
• plant development