Basidiomycetes as Eco-Friendly Biocontrol Agents Against Postharvest Fungal Pathogens

Postharvest losses of fruits and vegetables attributable to phytopathogenic fungi and suboptimal handling practices remain a critical challenge worldwide. Ubiquitous postharvest pathogens, including Alternaria alternata, Botrytis cinerea and Fusarium avenaceum, are responsible for severe decay during both pre-harvest and postharvest stages. Several of these fungi are also capable of producing toxic secondary metabolites, commonly referred to as mycotoxins, posing additional risks to food safety. Disease control strategies have traditionally relied on the extensive application of synthetic fungicides during crop production and storage. Nevertheless, increasing concerns regarding fungicide resistance, environmental sustainability, and consumer health have prompted the search for alternative, eco-compatible disease management approaches. In the present study, basidiomycete strains belonging to the genera Ganoderma, Laetiporus and Fomitopsis, known for their applications in traditional medicine, were morphologically and molecularly characterized and assessed for their biocontrol potential against selected postharvest fungal pathogens. Antagonistic activity was evaluated using both living mycelia and cell-free culture filtrates on different growth media, under in vitro and in vivo conditions. The tested basidiomycetes did not exert any phytotoxic effects on the host fruits and significantly suppressed pathogen growth. Notably, extracellular metabolites present in the basidiomycete culture filtrates exhibited pronounced antifungal activity, leading to a marked reduction in pathogen viability. Furthermore, in vivo assays demonstrated a decreased capacity of the phytopathogens to colonize fruit tissues following treatment. Although validation through large-scale and commercial trials is required, these results indicate that basidiomycetes represent a promising source of biological control agents for the sustainable management of postharvest diseases.