At the whole plant level, water scarcity induces complexchanges in C and N metabolism resulting from modifications in theavailability of nutrients (Foyer et al., 1998; Imsande and Touraine,1994). In addition to the discussed changes in carbon assimila-tion, water stress may restrain nitrate acquisition by the roots,as well as restrict the ability of plants to assimilate and reducenitrogen (Yousfi et al., 2012; Kocheva et al., 2007).