The fungal endophyteFusarium solaniprovokes differential effects on the energy balance of twoLotusspecies

Abstract

AbstractBackground and aimsThe interactions established between plants and endophytic fungi span acontinuumfrom beneficial to pathogenic associations. The aim of this work was to explore the mechanisms underlying the potentially beneficial effects provoked by a fungal strain in legume species of the genusLotus.MethodsThe ability to solubilise phosphorous was evaluated in nine fungal strains isolated from roots ofL. tenuis. A selected strain was further assessed for its ability to colonize plant roots in differentLotusspecies. The effects of the two interactions were assessed by analysis of the photosynthesis, sugar amount, and macronutrient status of leaves and roots.ResultsA fungal isolate identified asFusarium solanishows the highest phosphate-solubilisation activity and grows endophytically in roots ofL. japonicusandL. tenuis. Fungal invasion enhances plant growth inL. japonicusbut provokes a contrasting effect inL. tenuis. Photosynthesis, sugars and K content showed a differential effect in both plant species.ConclusionsOur results indicate neither of the plant species evaluated in this work were significantly stressed byF. solani. Thus, the differential responses observed are due to distinct mechanisms involving photosynthesis, potassium homeostasis, and carbohydrate metabolism that are employed by plants to maintain fitness during the endophytic interaction.