Résumé
Wheat production represents a major economic value with a world production at 785 million tons, France being the first producer and exporter in Europe (26.3Mt). It is thus necessary to ensure its stability and quality, and to assess the effect of extreme predicted climate changes (https://www.ipcc.ch/report/ar6/wg3/) on grain characteristics and corresponding transformed products. Product quality depends on the grain behavior during processing, which has an impact on the fate of each grain tissues, particularly the separation between the starchy endosperm from the outer layers. On one hand, this behavior depends on the mechanical properties of the grain, mainly controlled by the Ha (Hardness) locus, located on chromosome 5D in common wheat and carrying two specific proteins, Puroindolines (Pins) A and B. It also depends on growing conditions, which may influence grain filling and then milling behavior. With this in mind, wheat near-isogenic lines differing only by a mutation in the gene encoding Pin B, and thus differing by hardness, were grown for two years on the Pheno3C platform in Clermont-Ferrand under normal (well-watered, atmospheric CO 2 : 412ppm) and stress conditions (water deficit and/or increased CO 2 , 600ppm, using a Free Air CO 2 Enrichment system). The presented work will analyze the impact of these distinct climatic conditions on wheat grain characteristics and milling behavior according to the different class of wheat hardness.