Control of Alternaria post-harvest infections on cherry tomato fruits by wild pepper phenolic-rich extracts

The use of plant-derived products in postharvest disease management may be a valid alternative to conventional chemical treatments. In this study, the antifungal activity of crude foliar extracts of a wild Capsicum annuum accession against Alternaria alternata was assessed. Pepper extracts affected mycelial growth and suppressed conidia germination in a dose-dependent manner. Moreover, they significantly reduced soft rot disease severity on artificially infected ripe cherry tomatoes. Extracts were characterized for their total phenolic content and antioxidant activity. UPLC-DAD analysis was also performed to obtain phenolic profiles of extracts and quantify the individual known components, including gallic acid, chlorogenic acid, catechin, caffeic acid, p-coumaric acid and ferulic acid. The putative role of this class of molecules in conferring antifungal activity to the extracts is discussed. The results indicate that extracts rich in natural phenolic compounds could be promising for sustainable applications in crop protection.