Résumé
Pearl millet is a cereal crop that is given a little attention by researchers despite its tremendous capabilities with respect to its pears (wheat, barley, ...). This plant cultivated in arid and semi-arid areas in Western Africa and Sahel resisting low rainfall and poor soil conditions is the main food and cheapest nutritive source for people living out there. When speaking about such stresses, we are directly involving the root traits (growth and exudation) that are responsible for water uptake and nutrient acquisition and their interaction with soil and inhabiting microbiota.As part of an ANR project*, 188 pearl millet inbred lines were selected based on the amount of root exudates produced and the architecture of the roots. Four different pearl millet lines with contrasting properties in term of root growth and exudation have been selected to decipherer the metabolic interactions and reveal the structure-function of root associated microbiota. The four selected inbred lines were grown whether in a hydroponic system or in soil in Bambey (Senegal). The metabolites were extracted from roots, shoots and rootadhering soil (RAS) for plants grown in Bambey soil (Senegal), and from roots, shoots and growth solution for plants grown under hydroponic conditions. The extracted metabolites were analyzed by the Fourier transform ion cyclotron resonance mass spectrophotometer (FTICR-MS). In parallel, RNA was extracted from bulk soil, RAS and from roots for 16S and ITS metabarcoding and metatranscriptomic analysis. Identification of the microbial populations most influenced by changes in pearl millet exudation and the correlation between these populations and specific metabolic pathways and compounds from roots, shoots and root exudates will be discussed.