Assessment of essential oil yield of Artemisia herba-alba cultivated in Tunisian arid zone

The main objective of this study is to estimate the essential oil (EO) yield of Artemisia herba-alba through biomass prediction. EO yield dependent in both the biomass production and its EO content, was determined from the recovered biomass after harvest of the upper half of plant tuft. The bio-volume parameter of twenty cultivated individuals of A. herba-alba were estimated four times during four years from height and diameters measurements. In the first harvest, after one year of establishment, several individuals appeared more productive than others. Thus, the canopy diameters of the plant tuft and the bio-volume recorded little significant relationship with the EO yield (R-2 = 0.47 and 0.57, respectively). Harvesting the upper half of plant tuft, the spherical volume model developed by the regenerated material of the same individuals resulted in a high correlation between the EO yield and both the mean diameter (R-2 = 0.61 to 0.62) and the bio-volume (R-2 = 0.66 to 0.83).