In vitro efficacy of essential oils against Colletotrichum gloeosporioides, the causal agent of Anthracnose

Abstract

Colletotrichum gloeosporioides Penz, the anthracnose disease causing fungal pathogen, accounts for up to 50% of spoilage of fresh fruits and vegetables. The present study explored a non-chemical approach for controlling postharvest anthracnose disease. Antifungal activities of essential oils from thyme (Thymus vulgaris L), betel leaf (Piper betle), cinnamon (Cinnamomum verum) and oregano (Origanum vulgare) were determined against C. gloeosporioides through in vitro poisoned food technique. Partial or complete inhibition of the pathogen was recorded using oils from thyme, betel leaf, cinnamon, and oregano at 100-400 ppm levels. Regarding the EC50 values, the antifungal activity of cinnamon oil was highest, followed by oregano, thyme and betel leaf. Characterization through GC-MS yielded the major constituents from thyme oil as thymol, cymene; caryophyllene in betel leaf oil; trans-cinnamaldehyde in cinnamon oil and carvacrol in oregano oil. The findings suggest that natural plant-based essential oils can emerge as promising agents for preventing spoilage of horticultural commodities from anthracnose disease.