Effect of Altitude on Rosmarinus officinalis L. Essential Oil in Murcia (Spain)

Rosmarinus officinalis L. is a Mediterranean shrub that can be located in almost all of Spain. It is known that for this species the essential oil yield and chemical composition can vary depending on the edaphoclimatic conditions of the growing area. For this reason the present study shows the results obtained for 23 rosemary populations harvested in Murcia (Southeast Spain), from different geographical areas. Essential oil yield (%EO) values ranged from 1.2 to 3.2, showing a positive statistical significant correlation (p<0.001) between the altitude of the area and this parameter (%EO= 1.434+0.00097*altitude; R-2 adjusted = 0.657). Related to the essential oil volatile profile, among the major components quantified (26) only beta-pinene and (E)- beta-caryophyllene showed a positive statistical significant correlation (p<0.01) between the altitude of the area and their relative concentrations, whereas for borneol a negative correlation between both parameters was detected (p<0.01).