Relationship Between Soil and Essential Oil Profiles in Salvia desoleana Populations: Preliminary Results

Salvia desoleana is a herbaceous perennial shrub endemic of Sardinia (Italy). The leaves are a source of essential oil, used in pharmaceutical and cosmetic industries. The therapeutic function of this species has been associated to the presence of essential oils rich in ?/?-pinene, ?-cimene, linaool, linalyl acetate and 1,8 cineole. Today the industrial request of Salvia genus essential oils is increasing and most of the biomass is exploited from the natural populations which are under severe risk of genetic erosion. In order to improve the essential oil production, the study of the environmental parameters that influence composition, quality and quantity of the essential oils, turns out to be necessary. Soil physical and chemical structure represents one of the determinant factors in secondary metabolites production, and could also be involved in volatiles fraction composition in the same species. The main aim of this research was to explore the relationship between essential oil profiles and soil characteristic in S. desoleana populations. GC/MS analysis performed on the essential oil extracts identified 22 principal compounds, which are extremely variable among the 5 S. desoleana populations studied. The analysis of the essential oils revealed different composition in the terpenes fractions: 68.18% of monoterpenes, 27.27% of sesquiterpenes and 4.55% of diterpenes. Analysis of chemical and physical soil parameters at the collection sites, revealed that silt and sand contents were correlated to ?-pinene and sclareol fractions and the total K2O was significant correlated to several compounds belonging to the three terpenes fraction identified. These results will provide guidelines for the in site conservation and for the improvement of the commercial value of the species