Thesis title: Study of the reactivity of root exudates with trace metals

The objective of this thesis is to investigate the diversity and reactivity of root exudates from dicotyledonous plants, in particular Arabidopsis thaliana (a model plant) and Noccaea caerulescens (a metal hyperaccumulator), regarding trace elements (TE), including iron, in the rhizosphere.

Plants secrete into the soil a wide range of organic ligands that play a central role in the mobilization of iron and in interactions with both metallic and non-metallic trace elements. This work aims to identify the composition of root exudates, characterize the factors influencing their production, and analyze how these exudates contribute to the complexation, mobilization, and immobilization of these mineral elements. The approach will rely on metabolomic analyses and experiments under different environmental conditions.

The expected results will provide a better understanding of the mechanisms regulating plant mineral homeostasis and their ability to adjust nutrition in response to environmental constraints. They will highlight the role of root exudates in phytoremediation (plant-based soil decontamination) and in the sustainable management of mineral elements, thus contributing to the optimization of fertilization practices and the restoration of contaminated soils.