Effect of Altitude, Temperature and Soil on Essential Oil Production in Thymus fedtschenkoi Flowers in Osko and Surrounding areas in Iran

Abstract

Thymus fedtschenkoi Ronniger (Lamiaceae) is an endemic Iranian species of the genus Thymus, and well distributed through out in the rocky slopes of Caucasus and Western Asia. The effect of altitude, temperature and soil on essential oil production in T fedtschenkoi flowers growing in Osko and surrounding areas in Iran was studied. The distillation of flowers of T fedtschenkoi Ronniger collected from four different places in and around Osko, e.g. Eskandan, Fesendegh, Koohdel and Osko, produced 2.62, 3.20, 2.22, and 2.64 % essential oils, respectively. While the volume of production of essential oils was clearly affected by the above factors, the chemical profiles of the samples collected from these places were quite similar with minor differences in composition. All samples were composed predominantly of monoterpenes including monoterpene hydrocarbons (11-25 %), monoterpene alcohols (2-4 %), monoterpene phenols (similar to 69-79 %).