Inhibitory Effect of Some Essential Oils on Control of Green Mold (Penicillium digitatum) and Postharvest Quality Parameters of Lime Fruit

Green mold rot disease caused by Penicillium digitatum is the most economically important postharvest disease of lime fruit in all production areas. In this research, effects of essential oils (Cinnamomun verum, Eugenia caryophyllata, Thymus vulgaris, Zataria multiflora) for controlling green mold in Mexican lime (Citrus aurantifolia cv. Mexican lime) fruit were studied. Mexican limes were inoculated by Penicillium digitatum suspension and were immersed with the essential oils at three levels 0 (as control), 0.1 and 0.2% (v/v). Then, fruits were kept at 8±1oC and 90-95% relative humidity for 21 days. The results showed that the essential oils significantly affected fruit decay, weight loss, L*, a*, b*, total phenolic content and total antioxidant activity. After 21 days of storage, total phenolic content and total antioxidant activity of treated fruit with essential oils were higher compared with the control. In addition, essential oils were effective in decay and water loss control, and decreasing L* and b* compared with the control. The garden thyme essential oil at 0.2% decreased postharvest decay seven times lower than control but increased total phenolic compounds and antioxidant activity compared to the control 21 days after storage. Therefore, garden thyme essential oil has a strong effect on controlling green mold and maintaining quality of Mexican lime fruit.