Document Type : Research Paper

Authors

• A. Mohammadian ¹
• R. Karamian ²
• M. Mirza ³
• A. Sepahvand ²

¹ Research Center for Agriculture and Natural Resources, Khorramabad, Lorestan, Iran

² Research Center for Agriculture and Natural Resources, Khorramabad, Iran

³ Research Institue of Forests and Ranglands, Tehran, Iran

Abstract

Thymus is one of the most important genera of the Lamiaceae family, belonging to the Nepetoideae sub family. In this study, the relationship between altitude from sea level and soil physical and chemical characteristics as important factors affecting the quantitative and qualitative essential oils of Thymus fallax Fisch.et C.A. Mey.were examined. Four natural habitats of this species (Zagheh, Alashtar, Razan and Rhimeleh) were selected. Aboveground samples were collected in flowering stage and the essential oils were extracted with hydrodistilation method. Essential oils composition was determined using GC & GC/MS. Data analysis was performed by SPSS software, and Duncan's Multiple Range Test was used for mean comparison. According to the obtained results, the highest essential oil was recorded for Rhimeleh (2.8 %w/w) as compared to other habitats. The main components in the essential oils were carvacrol, thymol, gamma- terpinen, p-cymen, champhen and geranial. With increasing altitude, the percentage of carvacrol and thymol increased significantly. Some soil characteristics were correlated with the essential oils, presented in a linear regression model.

Keywords

• Thymus
• Altitude
• soil characteristics
• Essential oils
• Lorestan