Résumé
Iron is an essential element for living organisms. However, in most cultivated soils, iron availability is low despite its abundance due to soil physicochemical properties, including relative oxygen pressure and pH. Therefore, there is a strong competition for this element, required for plant and microorganism physiology, but showing a low availability. This competition relies on active strategies of iron uptake, which have been developed by plants and microorganisms. The efficacy of the corresponding strategies differs according to the organisms and results in interactions ranging from competition to mutualism, which impact plant growth and health. This chapter reviews strategies and methodologies, applied in literature, to monitor iron bioavailability, characterize the impact of this bioavailability on rhizosphere microbial communities, and assess the consequences on plant health and growth.