C-13/C-12 discrimination measured in tartrate and sugars in mature grapevine berries

Carbon discrimination expressed as delta(13)C, is an indicator of water str ess in the period of carbon assimilation. delta(13)C values of tartrate and sugar of berries collected from vineyards with very contrasting climates a re compared. A significant relationship between delta(13)C values and water stress is reported. The grapevine water stress status before and after ver aison can be evaluated by measuring delta(13)C values of tartrate and sugar in mature berries. The delta(13)C values depend also on the rootstock and the variety. The usefulness of this measure to characterize vineyard enviro nmental characteristics is discussed.