Examining the response of Botrytis cinerea to aqueous ozone: inactivation kinetics, structure, physiology, and growth in different strawberries cultivars

This work aimed to study the kinetics and mechanisms of Botrytis cinerea conidia inactivation by aqueous ozone treatments (2.5 ± 0.8 mg O 3 L −1 and 4.2 ± 0.2 mg O 3 L −1 , 0.5-16 min), using conventional plate count technique, flow cytometry analysis (FCM), and transmission electron microscopy (TEM). The effect of treatments on the mold incidence on two artificially contaminated strawberries cultivars over refrigerated storage (6 ± 1 °C) was also investigated. The inactivation pattern of B. cinerea conidial suspensions depended on initial level of the microorganism, dissolved ozone concentration and treatment time. Non-linear survival curves were obtained and fitted successfully with the Weibullian model. FCM and TEM analysis revealed alterations in the physiological state and ultrastructure of ozonated conidia that depended on the ozone dose. Ozonation (4.4 mg O 3 L −1 , 5-10 min) reduced B. cinerea incidence throughout storage in strawberries of cv. Fortuna, but no effect was found in cv. Aroma.