Alice Rossille

Team : FeROS

Supervisor : Christian Dubos

Title :  Study of coumarin uptake by roots, a key mechanism in plant iron nutrition

Abstract : Iron is an essential micronutrient for plants but is often unavailable in soils with neutral to alkaline pH. A newly identified mechanism in non-grass plants involves the secretion of coumarins, which mobilize insoluble Fe3+ by forming complexes, enabling iron absorption and storage in root cell vacuoles. My project focuses on understanding the dynamics of coumarin transport (including soil uptake, intercellular movement, vacuolar storage, and regulation based on iron availability) by characterizing newly isolated loss-of-function Arabidopsis thaliana mutants.

Cannelle Armengaud

Team : Systems – IPSiM

Supervisor : Sandrine Ruffel

Title :  Strategies of adaptation of the root acquisition system in a heterogeneous nitrate environment in Arabidopsis

Abstract : The root system, the anchoring organ of plants, fulfils the function of acquiring water and nutrients. As plants frequently encounter heterogeneous soils, their balance between resource exploitation and soil exploration must be optimised, particularly as the latter is a necessary but costly process. The aim of my thesis is to better understand and model the behaviour of the root system when faced with a choice between environments that differ in terms of nutrient availability. Optimisation of the ‘split-root’ experimental system will enable dynamic measurement of root system architecture in response to nitrate heterogeneity, which will be the subject of algorithmic modelling. In addition, the system will also be used to identify relevant targets that decouple the development/growth and transport functions in order to improve nitrate acquisition in plants by studying a range of genotypes of interest.