Exploring the Impact of Apocarotenoids on Pathogenic Fusarium oxysporum f.sp. lini and Endophytic Fo47 strains

Abstract

The Fusarium oxysporum species complex (FOSC) contains highly specific plant pathogens and some nonpathogenic strains, such as Fo47. In our work we concentrated on Fusarium oxysporum f.sp. lini (Foln), the specific flax pathogen and the endophytic strain Fusarium oxysporum 47 (Fo47), which is possibly protective for flax against pathogens. We investigated the influence of apocarotenoids like ionones and abscisic acid (ABA) on growth and development of these fungal strains considering possible fungicidal abilities of mentioned substances and comparing responses of fungi. The study shows inhibitory effect of ionones on mycelium growth of both Foln and Fo47. Our results also show the differences in apocarotenoids effect on studied strains in regards of sporulation, FUB genes cluster activity and fusaric acid (FA) production. Author summaryIn this study, we investigated the interaction between Fusarium oxysporum, a fungus that can either harm or potentially benefit plants, and natural plant-derived compounds known as apocarotenoids. We focused on two fungal strains: one that specifically infects flax plants, causing disease, and a nonpathogenic strain that may protect flax from pathogens. By examining the effects of apocarotenoids like ionones and abscisic acid, we aimed to understand how these compounds influence fungal growth, sporulation, toxin production, and gene activity related to pathogenicity. Our findings reveal that ionones inhibit the growth of both strains, suggesting their potential as antifungal agents. Interestingly, the two strains showed distinct responses to these compounds, particularly in their production of fusaric acid and activation of toxin-related genes. These results highlight the complexity of fungal interactions with plant-derived molecules and suggest that apocarotenoids could play a role in modulating fungal behavior. This work contributes to our understanding of plant-fungal interactions and may inform future strategies for managing crop diseases sustainably.