Mahshad Nasrolah Alhosseini - Department of Horticulture, Science and Research Branch, Islamic Azad University, Tehran, Iran
Mohammadreza Labbafi - Medicinal Plants Research Center, Institute of Medicinal Plants, ACECR, Karaj, Iran
Iraj Mehregan - Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
Hassanali Naghdi Badi - Department of Agronomy and Plant Breeding, Faculty of Agriculture, Shahed University, Tehran, Iran
Ali Mehrafarin - Medicinal Plants Research Center, Institute of Medicinal Plants, ACECR, Karaj, Iran

Stachys laxa, Boiss. & Buhse a member of the Lamiaceae family, is a medicinal and aromatic that found in semi-cold and Mediterranean regions of northern Iran. The essential oil composition of Iranian pof S. laxa were evaluated in this study. The ۱۶ populations of S. laxa were collected from North of Iran. The essential oils were extracted by hydrodistillation using Clevenger type and were analyzed by GC and GC/MS. Based on the essential oils analysis, ۳۷ different chemical compounds were identified in this study within the sixteen populations of S. laxa. The results revealed that distinct differences in the content of compounds depending on region of sample collection. The main constituents of the identified essential oils were β-Elemene (۱.۱-۱۸.۷%), trans-Caryophyllene (۰-۱۳.۲%), Germacrene D (۱.۱-۴۶.۶%), and Caryophyllene oxide from (۰.۳-۳۲.۳%). According to the GC/MS results, some components such as Germacrene A, Spathulenol, Germacrene D, and α-cadinol were the effective components to separate different populations of S. laxa. In general, the lowest and highest content of germacrene D was founded from ۱.۱ to ۴۶.۶% in the population of Kiasar (KSR), and Chalus (CHL), respectively. The S. laxa populations had high diversity in term of essential oil components, which could be considered in future studies.

germacrene D, population, Lamiaceae, GC/MS analysis