lasticity of Lotus spp.-Fusarium spp. interactions: Physiological traits beyond the mutualism-pathogenesis continuum

NIEVA, A.S.; ERBAN A.; RUIZ O.A.; KOPKA J.

PORTO ALEGRE. BRASIL

Congreso; XVIII BRAZILIAN CONGRESS OF PLANT PHYSIOLOGY; 2022

BRAZILIAN SOCIETY OF PLANT PHYSIOLOGY

Interactions between plants and fungi span a continuum from beneficial to pathogenic associations. The forage legume Lotus tenuis constitutes an important forage source in constrained environments due to its capacity to tolerate stress conditions. Moreover, it has been correlated with Fusarium spp. Fusarium species are key pathogens of important crops. However, some Fusarium species including the F. solani Species Complex, establish endophytic interactions with legumes, being these interactions a suitable model to study the plant-fungal interactions in the continuum mutualism-pathogenesis.We aimed to determine the effect of Fusarium spp. infection on the crop L. tenuis and the model L. japonicus. The plasticity of Lotus spp.-Fusarium spp. interactions was tested by infecting the roots with endophytic and pathogenic Fusarium strains. We characterize the interactions by using morphological, microscopy, molecular, metabolomics and transcriptomics approaches.F. solani caused growth promotion in L. japonicus, while the impairment of the biomass was evidenced in L. tenuis (dual behaviour). F. culmorum and F. poae were pathogens of L. japonicus, while L. tenuis exhibited an initial pathogenesis stage and further recovery to normal conditions. On the other hand, F. tricinctum, F. avenaceum and F. graminearum displayed pathogenic effects in both plant species. Our results demonstrated a differential fungal infection rate between plant and fungal speciesand alterations in the metabolism homeostasis. Additionally, the amount of lipids secreted by roots in response to the fungal infection was proportional to the fungal aggressiveness.