Response of grapevine (Cabernet Sauvignon cv) to above ground and subsurface drip irrigation under arid conditions

The response of wine grapes to irrigation systems was investigated in a Cabernet Sauvignon/140 Ru vineyard in sandy loam soil in Sicily during a two-year study. Two different drip irrigation systems were evaluated: one surface drip and two subsurface drip irrigation systems, with the trickle line located at different distances from vine trunks. Vegetative and quantitative parameters, must quality and root distribution were compared among irrigation treatments. During the two study years, irrigation of grapevines via a subsurface drip system resulted in greater water use efficiency without affecting must composition. Establishing the trickle line near the trunk positively influenced trunk growth and total root contact while establishing the trickle line 1.20 m from the trunk increased yield. Dry mass partitioning was modified in subsurface irrigation treatments in favour of reproductive organs. We conclude that subsurface drip irrigation under the trunk can be successfully used under water deficit irrigation management, even in sandy loam soil and in the hot climate conditions of the Mediterranean vineyard. Some aspects of management deserve further investigation and further studies may better define the optimum conditions for the successful utilization of the SDI 120 irrigation strategy.