Exploring the interplay between flavonoid content and mycorrhizal colonization in roots of woody invasive aliens and non-invasive native counterparts
V. BORDA, M. BURNI, P. BUSTOS, G. ORTEGA, C. URCELAY
Instituto Multidisciplinario de Biología Vegetal, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba. Av. Vélez Sarsfield 1611

Woody invasive plants have profound impacts on community composition and ecosystem dynamics worldwide, underscoring the need to understand the mechanisms driving their invasive potential. Through a recent extensive literature review, we found that woody invasive species exhibit diverse flavonoids, particularly within the flavonol group at the root level, compared to non-invasive species. These flavonoids serve critical roles as chemical signals in belowground interactions, potentially influencing invasion processes. In a phylogenetically balanced design, we investigated flavonoid composition and colonization by arbuscular mycorrhizal fungi (AMF) and dark septate endophytic fungi (DSE) in roots of invasive woody species and their non-invasive native counterparts (9 pairs) from central Argentina. Flavonol richness and content showed no significant differences between invasive and native species, but the flavonol rutin was higher in invasives. Additionally, invasives exhibited higher levels of arbuscule colonization and lower DSE colonization. Remarkably, we observed negative correlations between root flavonoid richness and AMF colonization, and between flavonoid content and DSE colonization in woody invasives, but not in their non-invasive native counterparts. These novel findings highlight the complex interplay between flavonoids and fungal symbionts in the root systems of invasive woody plants, shedding light on potential mechanisms underlying their invasive success.

Keywords: Woody invasive plants, flavonoid production, fungal colonization, invasion ecology, belowground interactions.