Assessment of the antifungal potential of the essential oil from Thymus vulgaris against Botrytis cinerea causative agent of postharvest grey mould on strawberry fruits

Abstract

Depending on commodity and region, postharvest diseases can cause considerable economic losses. Although effective against postharvest pathogens, synthetic pesticides have gained increasingly negative attention over the past years from the public opinion. Among natural fungicides, plant derived compounds such as essential oils (EOs), have become topic of increasing discussion over the last couple of decades as safe and ecologically friendly alternatives to synthetic pesticides. Grey mould caused by Botrytis cinerea is an important postharvest disease of strawberries and many other horticultural products. In the present study the antifungal potential of Thymus vulgaris essential oil was tested on individual strawberries artificially inoculated with Botrytis cinerea. Two dilutions of thyme essential oil, 200 μl/ml and 500 μl/ml, were applied to strawberry fruits and incubated for a period of 13 days. The dilution 500 μl/ml effectively suppressed fungal growth in strawberries for a period of 7 days, more than twice as long as the control group. Furthermore only one out of five replications in the 500 μl/ml treatment was visibly infected while the others remained free from infection for the entirety of the experiment. At experiment conclusion the strawberries in the 500 μl/ml treatment maintained a healthier shape, firmness, and colour compared to the control and 200 μl/ml treatment. This study has confirmed that the application of thyme essential oil could be an efficient biocontrol tool in postharvest stage.