LAUSR

The chemical composition and structure of the soil strongly affect the growth and development of plants. Ecophysiologically, the effects of soil are translated in changes in plant primary and secondary metabolism. Among the secondary metabolites of plants affected by soil properties are essential oils. In this work, we resume our study on the effect of soil properties on the accumulation of essential oils in two spontaneous plants growing in Algerian semiarid region: Rosmarinus officinalis L. and Thymus algeriensis Boiss & Reut. after studying the effect of climate on these plants in the same period (2010–2014) and at the same collection site in our previous study. The results showed significant differences (P < 0.001) between the oil contents during the period of the study in both plants. The yield of oils was significantly affected by the soil parameters. The pH, total calcium carbonate (CCE), active calcium carbonate (ACCE), and N:P ratio exhibited significant positive correlation (P < 0.001 and P < 0.05) with Rosmarinus officinalis essential oil amount contrary to total nitrogen and salinity that had negative effects. Regarding Thymus algeriensis, the pH, salinity, and N:P ratio had a significant positive effect (P < 0.001) on the content of essential oil. However, CCE, ACCE, and carbon exerted negative effects on oil amount.