Efficacy of biofumigation with essential oils in the control of postharvest rots on nectarines

The most common postharvest pathogens on nectarines are Monilinia fructicola (G. Winter) Honey and M. laxa(Aderh. &Ruhland) Honey, the agents of brown rot. The efficacy of five essential oils (EOs) at 0.1%, 0.5% and 1% concentration was evaluated in vitro against M. fructicola strain CVG1539 after 14 days at 25°C. Subsequently, biofumigation was realized with the three most effective EOs (fennel, basil, and lemon), this time at 2% concentration. Disease incidence was evaluated after a longer storage (28 days) at 1°C and after further 5 days shelf-life at 20°C. At the end of storage, nectarines treated with EOs showed a significant reduction in rots, which were caused by Monilinia spp. At the end of shelf-life, Monilinia spp., Penicillium spp., Botrytis spp., Alternaria spp., and Rhizopus spp. were isolated from the rots. Fruit quality and microbiome composition were analysed at harvest, after 28 days of storage, and after 5 days of shelf-life. The firmness in the treated fruits with EOs was higher compared to the untreated ones. Treatments with biofumigation with EOs are promising tools for the control of postharvest rots.