Essential oil analysis and phytotoxic activity of Ferula assa-foetida L.

This investigation was conducted to determine the essential oil composition and allopathic properties of anghuzeh (Ferula assa-foetida L.) medicinal plant. The experiment was completely randomized design in a factorial arrangement with two factors and three replications. The factors were six concentrations of 0، 200، 400، 600، 800 and 1000 ppm of the essential oil and five plant species including three weed species، Sinapis arvensis، Acroptilo repens، and Cardaria draba as well as two crops i. e. Triticum aestivum and Hordeum vulgare. The essential oil used in this study was extracted by hydro-distillation from the latex of the plant. The obtained oil was analyzed by Gas chromatography (GC) and Gas chromatography–mass spectrometry (GC-MS). To assess the allopathic effects of the oil on the studied species، a number of growth parameters such as seed germination، radical and plumule length as well as their dry and fresh weight، and abnormality percent of the seedlings were evaluated. The results of this investigation showed that the Anghuzeh essential oil had significant (p ≤ 0. 05) allelopathic effect on the studied weeds and crops. The comparisons among the means indicated that the response of the species to the oil were quite different. For example، Triticum aestivum showed maximum germination percent in the presence of different oil concentrations. While، the germination of Hordeum vulgare، Acroptilon repens، and Cardaria draba showed more susceptibility to the oil. Moreover، the results of the essential oil analysis indicated that a total of 13 components were identified in the oil of which α-Pinene (21. 3%)، β- Pinene، (47. 1%) and 1،2-Dithiolane (18. 6%) were the major compounds. The observed allelopathic effects of the essential oil are regarded to oil components and their synergistic effects. The findings of this study are the first step to use of Anghuzeh essential oil as a natural herbicide. Further investigations are still required for practical and commercial application of this method.