Lopes, C.M.Vicente-Paulo, J.Santos, T.Rodrigues, M.L.Barroso, J.Chaves, M.M.2022-01-122022-01-122001Lopes, C.M., Vicente-Paulo, J., Santos, T., Rodrigues, M.L., Barroso, J. e Chaves, M. M., 2001. An attempt to quantify grapevine water stress in a mediterranean environment. Compte Rendu XII émes Journées GESCO, Agro Montpellier/ENSAM, Montpellier, França, 3-7 Julho, Vol. 1: 43-48http://hdl.handle.net/10400.5/23011Aiming to quantify the effects of the intensity and duration of grapevine water stress, physiological and agronomical data from an irrigation experiment conducted during 1999 at Alentejo, south of Portugal, with the red variety Aragonez (syn. Tempranillo) were correlated with an water stress index (Sψ). This index was calculated by the integral of predawn leaf water potential below –0.2 MPa between bloom and harvest. Significant relationships were found between the Sψ, yield components and berry composition. The multiple regression analysis shows that the Sψ in the period bloom-veraison has a higher contribution to explain the variation in berry weight, anthocyanins and phenolics concentration than the Sψ in the period veraison-harvest. The knowledge of those relationships, together with the relationship between available soil water content and predawn leaf water potential, may allow the adequate management of soil water availability to optimise the yield/quality ratio for each ecological situationengpredawn leaf water potentialwater stress indexTempranilloconference object