Comprendre les performances et l'adaptation de deux variétéspopulations de tomate (S. lycopersicum) dans un système agroforestier via l'étude du microbiome racinaire dans le cadre d'une recherche participative

Within the framework of the European project LIVESEED, this study aims at establishing the influence of the type of pruning applied to trees in an agroforestry system and of the grown variety of tomato on the composition of the tomato root microbiome, as well as the effect of the microbiome's structuration on the physical-biochemical quality of tomatoes. The results show an effect of pruning intensity on the biochemical profile of tomatoes, which have higher amounts of sugars, vitamin C and phenolic compounds in the non agroforestry control environment, and higher concentrations of acids under tree shade. The two tomato varieties tested (Rose de Berne and Coeur de Boeuf) have different biochemical profiles, resulting from farmer selection. The fungal communities are little influenced by the tomato variety but reveal different assemblages depending on the intensity of tree pruning, both at the community and phyla levels (Ascomycetes, Basidiomycetes and Glomeromycetes). These differentiations are explained from an ecological point of view in order to lead to a better understanding of plant-microorganism interactions in agroforestry systems. The correlations between the physico-biochemical quality of the fruits and the structuration of the mycobiome show an impact of the diversity of Ascomycetes and the specific richness of Glomeromycetes on the biochemical profile of tomatoes. The results are discussed under the holobionte hypothesis and its influence on plant breeding, in connection with on-farm selection.