This study investigated some physiological features in a 20-year-old ‘Italia’ vineyard cropped in Apulia, Italy. Five vines with brown-wood-streaking associated to Phaeoacremonium minimum (sin. Pm. aleophilum) and Phaeomoniella chlamydospora (BWSV), five with brown-wood-streaking and white-rot caused by Fomitiporia mediterranea (BWSWRV) and five healthy vines (HV) were surveyed. Bleeding xylem sap (BXS) collected at bud-break, symptomless and symptomatic leaves taken during stretched-out leaves, fruit setting, cluster closing and bunch ripening phenological phases were characterized. BXS from HV showed the highest total ascorbic acid level, while BWSWRV had the highest viscosity coefficient, glutathione concentration and growth regulators activity. Low fresh and dry weight, total chlorophyll concentration and the hight leaf surface, hydrogen peroxide and cell membranes damage were detected in leaves of diseased vines. Symptomless and symptomatic leaves of BWSV and BWSWRV exhibited low concentrations of ascorbic acid, reduced glutathione and redox state; moderate levels of dehydroascorbic acid and oxidized glutathione. Higher dehydroascorbate reductase and low ascorbate free radical reductase and glutathione reductase activities were showed by leaves collected from diseased vines. However, no differences were detected in ascorbate peroxidase activity. The decrease of oxidative status alters cell membranes integrity and could contribute to cell death and symptoms development on leaves.