Antifungal Effects of Four Plant Essential Oils on Botrytis cinerea in Laboratory Conditions

Background: Essential oils are very complex mixtures of compounds with variety of biological properties Objective: In the present study, the effect of Cumin (Cuminum cyminum), Sage (Salvia officinalis), Basil (Ocimum basilicum) essential oil at 250, 500, 750 and 1000 µL.L-1 and Thyme essential oil at 30, 60, 120, 250µL.L-1 on growth of Botrytis cinerea was investigated in in vitro condition. Methods: This experiment was carried out with two different methods: mixing of essential oil with fungal culture medium (SM) and Pisk Diffusion Method (PDM). Results: The results showed that inhibitory effect of essential oils on fungal growth is related to type and concentration of essential oils and treatment methods. The PDM is more efficient in controlling of B. cinerea growth than SM. Cumin, Sage and Basil essential oils inhibited the fungal growth completely in PDM at all applied concentrations. In SM, inhibitory effect was related to applied concentration. Cumin and Thyme essential oils at 250 µL.L-1 concentration inhibited the fungal growth, but Basil and Sage oils at the same concentration have no inhibitory effect against B. cinerea. The results of MIC (Minimum Inhibitory Concentration) and MLC (Minimum Lethal concentration) showed that essential oils used in this study at all applied concentrations with two different methods were fungi static, except Cumin at 1000 µL.L-1 in disk diffusion method that was fungicide. Conclusion: Essential oils are natural products that have fewer side effects than synthetic pesticides. More research is necessary to replace synthetic pesticides with new formulations of these natural compounds especially for maintaining of the horticultural product quality.