Abstract
The study examined the potential of essential oils for controlling gray mold disease of table grape caused by Botrytis cinerea. Essential oils of cinnamon and oregano were used in vitro and in vivo. Both oils reduced the mycelial growth of the pathogen at various concentrations (100, 200, 400, 600, 800, and 1000 mu l per liter). The most effective concentrations of both essential oils were 800 and 1000 mu L/L, which yielded the highest reduction in pathogen growth. Both oils reduced the spore germination of the pathogen at 800 mu L/L. In addition, cinnamon and oregano oils reduced the disease severity of gray mold by 58.9% and 42%, respectively. Each essential oil was able to increase peroxidase and polyphenol oxidase enzymes and phenol and flavonoid content in table grapes infected with B. cinerea compared with the control. Interestingly, essential oils increased total soluble solids, vitamin C (VC), and titratable acidity (TS) in fruits compared to the control. In conclusion, our study confirmed that cinnamon and oregano may be applied as future ecofriendly alternatives to synthetic fungicides for controlling gray mold disease.