This work has led to a very precise description of root hydraulics in Arabidopsis. In particular, it revealed a marked natural variability of this function. We could not confirm the idea that the previously identified Y accession could be a unique material for studying the response of plants to salt stress, as only Lpr but neither Lpcell nor aquaporin gene regulation showed an atypical regulation. By contrast, the identification of gene markers for Lpr, in combination with an increased throughput of Lpr measurements, pave the way to exploring water transport in the Arabidopsis root by quantitative genetics. The present project also reinforced the cooperation with our partner laboratory in Shanghai and allowed to recruit valuable collaborators for other projects in our laboratory.