Esca is a very complex disease that is usually noticed when the grapevine show external symptoms. However, the grapevines can be infected for a long period of time and rarely manifest the typical leaf symptoms. Moreover, little is know about the consequences of Esca on vineyard productivity. In Portugal, in Vinho Verde region, Alvarinho sub-region, most vineyards are infected with Esca. In this work we evaluate the impact of Esca on some physiological parameters of grapevines cv. Alvarinho.This preliminary work reveal the importance that these kind of physiological measurements can have in the valuation of the infected Esca grapevine physiological conditions. These results may be used as a pattern to predict the damage magnitude of Esca disease in grapevines.Fundação para a Ciência e a Tecnologia (FCT)Fundação Luso-American
