اثر ضدقارچی 15 اسانس گیاهی بر تعدادی از قارچ‌های بیماری‌زای گیاهی در شرایط آزمایشگاهی

This study was conducted to investigate the antifungal effect of 15 plant essential oils on some plant pathogenic fungi. The research was conducted in the form of a factorial experiment based on a completely random design with two factors of fungus and essential oil and with three replications. The essential oils included ajowan, galbanum, peppermint, rosemary, lavender, lemon grass, eucalyptus, ziziphora, thyme, mord, angelica, fennel, Stinking assa, sage, and marze. The studied fungi include Fusarium oxysporum f.sp. dianthii (Fod) causes carnation fusarium wilting, Fusarium oxysporum f.sp. medicagenes (Fom) causes fusarium wilt of alfalfa, Fusarium solani (Fs) causes fusarium root rot of beans and Tricharina gilva (Tg) causes grape stem rot. The antifungal activity of each essential oil was evaluated using the method reported by Fothergill (2012) with some modifications. The minimum fungicidal concentration (MFC) was determined separately with concentrations 0.1, 1, 10, and 100 ppm of each essential oil and with no visible growth of the fungi on the PDA culture medium and was incubated at 26 °C for 72 hr. The results showed that out of 15 essential oils, 5 essential oils (Angelflower, Ziziphora, Eucalyptus, Thyme, and Ajowan) could inhibit the radial growth of the fungi mentioned above and the highest percentage of inhibition with 40.66% related to Tricharina gilva (Tg) fungus. And the lowest inhibition percentage of 7.33% was related to (Fod). In the second test, 10 and 100 ppm dilutions of selected essential oils were mixed with a PDA culture medium as the pour plate method. A plug of half a square centimeter of each fungus was placed in the center of the culture medium, the results showed that the highest percentage of inhibition of the radial growth of the fungus with the values of 41.167% and 41% respectively related to Eucalyptus and Thyme and the lowest percentage of inhibition with 0% related to It was to Angelica. In the next step, only thyme essential oil in two dilutions of 25 and 75 ppm was examined on 4 fungi. The highest percentage of inhibition (56%) of fungus (Fod) was obtained at the dilution of 75 ppm and the lowest percentage of inhibition (26%) related to the dilution of 25 was the ppm of fungi (Fs).