Changes in root exudate composition mediated by pathogenic and mycorrhizal fungiin tomato (Solanum lycopersicum L.)

Abstract: Components in root exudates can act as signals and therefore play an important role intriggering plant–microbe interactions, such as colonization by pathogenic or symbiotic fungi.This work is based on a biological model system consisting of tomato (Solanum lycopersicum L.),the soilborne tomato pathogen Fusarium oxysporum f. sp. lycopersici (FOL) and the arbuscularmycorrhizal fungus (AMF) Glomus mosseae (GM) to assess metabolic changes in root exudationcaused by FOL and GM alone and in combination, respectively. In order to assess thesemetabolic changes, HPLC-PDA and quadrupol GC-MS analyses were performed with specialfocus on sugars, sugar alcohols, organic and amino acids, and secondary metabolites, such asphenolic acids and flavonoids. Furthermore, the exudates were tested on the development of FOLin vitro to give information about their influence on the initial behaviour and performance ofFOL.