| Description: |
International audience ; Fusarium species are causative agents of Fusarium head blight (FHB), a devastating fungal disease affecting cereal crops worldwide. FHB causes yield losses and grain contamination with mycotoxins (type A and B trichothecenes, zearalenone, enniatins, beauvericin), posing significant health and food safety concerns. Several Fusarium species occupying the same ecological niche during infection likely interact, modulating FHB outcomes, including symptoms and mycotoxin contamination. However, most studies have focused on single Fusarium species, particularly F. graminearum, considered as the main causal agent of FHB, which has proven to be insufficient for a comprehensive understanding of the disease.This study aims to investigate the species compositional and metabolomic dynamics of a synthetic community called Meta-Fusarium. This community was built with one strain of each of the seven major FHB species encountered in Europe (F. graminearum, F. culmorum, F. poae, F. avenaceum, F. sporotrichioides, F. langsethiae, F. tricinctum) and exposed in vitro to different abiotic pressures. Changes in temperature and oxidative stress, key abiotic constraints that Fusarium species must cope with during plant infection, were considered. Our data indicated that, regardless of the culture conditions, F. culmorum followed by F. graminearum and to a lesser extent F. poae, were the predominant species. Species composition was shown to be affected by abiotic factors, F. culmorum being favoured by a decrease in temperature while F. graminearum was more abundant under oxidative stress. Similarly, metabolomic profiles and mycotoxin accumulation by the Meta-Fusarium were influenced by abiotic conditions. While Type B trichothecenes were the dominant mycotoxins, whatever the culture conditions, the 15-ADON mycotoxin produced by F. graminearum, was quantified in higher amounts under oxidative stress.These results provide the first assessment of behaviour of a complex Fusarium synthetic community, moving towards a ... |