In Italy walnut cultivation is mainly concentrated in Campania region, where traditional and new specialized orchard coexist and international cultivars are utilized for the new plantations. The growth and productivity of the international, high yielding cultivar ‘Chandler’ grown in the dry summer conditions of Naples province has been examined during a two year irrigation trial. Three treatments were applied: an un-irrigated control and two different levels of water supply, corresponding respectively to the restitution of 50 and 100% ET0 by means of a drip irrigation system. Plant growth and nut and kernel weight increased at the highest irrigation volume, while nut fall at ripening was more concentrated in the un-irrigated control. The percentage of defected nuts was higher in condition of limited water availability. The restitution of 50% ET0 assured satisfactory levels of production and saving of irrigation water
