Background and Objectives: The antifungal activities of the essential oils and their constituents against some phytopathogenic fungi have been reported [1,2]. In order to reduce the use of synthetic fungicides, recently considerable attention has been given to search for naturally occurring compounds. A large number of studies have concerned the chemical compositions and antifungal activity of thyme’s oil [3,4]. The aim of the present work was to determine the chemical composition and antifungal activity of Thymus vulgaris oil cultivated in Iran. Methods: The essential oil from aerial parts of the plant at full flowering stage were subjected to hydrodistillation and chemical compounds analyzed by GC/GC-MS methods. The in vitro antifungal activity of the oil at different concentrations (100, 200, 400, 800 and 1600 µL-1) against three phytopathogenic (Drechslera spicifera, Fusarium oxysporum f.sp. ciceris and Macrophomina phaseolina) was evaluated by agar dilution method. The data were analyzed by ANOVA (SPSS 21 software). Results: Totally 45 compounds representing 96.75% of the oil were characterized which thymol (36.81%) and ρ-cymene (30.90%) were the main components of thyme oil. According to the results, the antifungal activity of the oil increased with a rising in concentration. In this study fungicidal activities only were observed on F. oxysporum and D. spicifera at higher concentrations than 800 µLL-1. Conclusion: The antifungal activity of T. vulgaris essential oil could be attributed to the high concentration of oxygenated monoterpenes (thymol) and monoterpene hydrocarbons (ρ-cymene) beside other minor compounds.

Keywords