Variability of the essential oil composition of cultivated populations of Salvia lavandulifolia Vahl

Spanish sage or lavender sage (Salvia lavandulifolia Vahl) is an aromatic plant with a high economic potential in agriculture because of its rusticity and low chemical inputs. However, the presence of numerous chemotypes hinders the supply of homogeneous crops to the industry and makes the selection and the standardising of the plant material necessary. With this aim, our group achieved an extensive population survey of this species across the Iberian Peninsula to investigate the variability of this species and started a selection program based in multienvironment trials. Thus, 12 wild populations of S. lavandulifolia have been grown in two different localities and their dry biomass production, yield, and composition of essential oil have been monitored during 2 yr of cultivation to evaluate the effect of the genotype x environment interaction on these traits. Each population presented a clearly differentiated composition of the essential oil, although camphor (15.3% average), 1,8-cineole (15.0%), alpha-pinene (11.3%), beta-pinene (8.5%), and limonene (7.5%) were the main compounds. Other compounds like p-cymene, gamma-terpinene, bornyl acetate, spathulenol, or viridiflorol were only present in some samples. The yield of essential oil ranged from 0.9 to 2.3 g per 100 g dry biomass, and the dry biomass from 76 to 322 g plant(-1). Despite the high variability of these traits, we inferred that the essential oil composition in S. lavandulifolia is chiefly determined by genetics which suggests that individual plants (clones) with a favorable composition for a specific application could be selected and bred with a homogeneous quality over time.