At the Cauquenes Experimental Station (INIA), Chile, duringthe 1976/77 and 1979/80 growing seasons, periodical samp)ing of different grapevine organs (cv. Pais, syn. Mission) were performed, in order to compare the arginine levels of plants with and without drip irrigation, Roots and canes of irrigated plants showed higher (evels of arginine, as compared with non irrigated plants, specially during the 1976/77 growing season, in which higher amounts of water were applied, preceeded by an NPK fertilization. The higher levels of arginine were measured in roots in the pre-bloom stage, being higher for the irrigated plants (2,62%), as compared with those not irrigated. The canes fol(owed the roots in arginine conteni, with higher levels in the irrigated vines (0.61%). For the other organs sampled, lower levels were meassured and no clear differences between irrigated and non irrigated plants were obtained.