Antifungal activity of volatile organic compounds from essential oils against the postharvest pathogens Botrytis cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa

Samuel Álvarez-García; Marwa Moumni; Gianfranco Romanazzi

doi:10.3389/fpls.2023.1274770

Antifungal activity of volatile organic compounds from essential oils against the postharvest pathogens Botrytis cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa

Front Plant Sci. 2023 Oct 4:14:1274770. doi: 10.3389/fpls.2023.1274770. eCollection 2023.

Authors

Samuel Álvarez-García^{1

2}, Marwa Moumni¹, Gianfranco Romanazzi¹

Affiliations

¹ Department of Agricultural, Food and Environmental Sciences, Marche Polytechnic University, Ancona, Italy.
² Plant Physiology Area, Engineering and Agricultural Sciences Department, Universidad de León, León, Spain.

Abstract

Gray mold and brown rot, caused respectively by Botrytis cinerea and Monilinia spp., are fungal diseases responsible for significant losses during the storage of fruit and vegetables. Nowadays, the control of postharvest diseases is shifting towards more sustainable strategies, including the use of plant secondary metabolites. In this study, the antifungal activity of Origanum vulgare, Thymus vulgaris, Thymus serpyllum, Melaleuca alternifolia, Lavandula officinalis, Lavandula hybrida, Citrus bergamia, Rosmarinus officinalis, Cinnamomum zeylanicum essential oils (EOs) in vapor phase was tested in vitro against B. cinerea, Monilinia fructicola, Monilinia fructigena, and Monilinia laxa. For the experiments, a protocol using a volatile organic compounds (VOC) chamber was designed. Results indicate a dose-dependent inhibitory activity of all the tested EOs, with O. vulgare, T. vulgaris, and T. serpyllum being the most active ones, with minimum inhibitory concentrations (MIC) of 22.73, 45.45, and 22.73 µl/L, respectively, against B. cinerea and a range between 5.64 and 22.73 µl/L against the three Monilinia spp. Overall, B. cinerea presented lower sensitivity to vapor-phase EOs than any of the Monilinia strains, except for the C. zeylanicum EO, which consistently showed higher inhibition against B. cinerea. Among the three Monilinia spp., M. fructicola was the least sensitive, while M. fructigena was the most sensitive. The use of VOC chambers proved to be a reliable protocol for the assessment of antimicrobial activities of EOs. These results suggest that the VOC emitted by the tested EOs are effective towards important decay-causing fungi, and that they could be used for the control of gray mold and brown rot in in vivo trials.

Keywords: VOC chamber; cinnamon; fumigation; lavender; oregano; rosemary; tea tree; thyme.

Grants and funding

The authors declare financial support was received for the research, authorship, and/or publication of this article. This work was conducted within PRIMA StopMedWaste “Innovative Sustainable technologies TO extend the shelf-life of Perishable MEDiterranean fresh fruit, vegetables and aromatic plants and to reduce WASTE”, which was funded by the Partnership for Research and Innovation in the Mediterranean Area (PRIMA), Project ID: 1556, a program supported by the European Union, and Euphresco BasicS “Basic substances as an environmentally friendly alternative to synthetic pesticides for plant protection” projects, and by Italy-China bilateral project “Biosynthesis regulation of metabolic markers and correlation with quality safety during fruit decay (BioQuaSa)”, funded by Italian Ministry of Foreign Affairs and International Cooperation. We acknowledge the Margarita Salas postdoctoral grant awarded to SÁ-G (Ministerio de Universidades; Plan de Recuperación, Transformación y Resiliencia; Universidad de León; Spain) financed by the EU-NextGenerationEU.