Study of various calcium magnesium quotients on growth characteristics and phenolic compounds of Thymus vulgaris L.

Thymus vulgaris L. is a medicinal plant belonging to the Lamiaceae. Different amounts of calcium and magnesium carbonate have shown a significant positive relationship with some of the active pharmaceutical ingredients. Accordingly, in this study, using calcium and magnesium carbonate and magnesium sulfate, the effects of differentcalcium to magnesium quotients (0.28, 0.8, 2, 3 and 8), which respectively contain 1 to 3.5, 2 to 2.5, 3 to 1.5, 1.5 to 0.5 (control) and 4 to 0.5 mM calcium to magnesium concentrations on some physiological indices of thyme were investigated in a completely randomized design. After about two months from the time of sowing, seedlings were transferred to a hydroponic culture medium that contained a Hoagland solution. After four weeks, the plants were harvested and the indices were measured. Theresults showed that the ratio of 0.8, resulted in significant increase of the most growth characteristics of thyme, including average leaf area, the fresh and dry weight of root and shoot compared to the control. The highest amount of phenolic compounds of thyme was observed at level 8 of calcium/magnesium treatment. The amount of phenolic compounds in the plant decreased compared to the control by increasing available magnesium. In general, it can be stated that 0.8 calcium to magnesium quotient was the best for the growth of the plant species, and 8 quotients was the best for phenolic compounds production