Combining cover cropping with deficit irrigation in a Mediterranean low vigor vineyard

Abstract

The aim of this research was to test the effects of vineyard soil management practices combined with deficit irrigation strategies on the performance of the grapevine ( Vitisvinifera L.) red variety Tempranillo. Two soil management practices (soil tillage – ST and permanent resident vegetation – RV) were combined with three deficit irrigation treatments (regulated deficit irrigation – RDI, partial rootzone drying – PRD and conventional sustained deficit irrigation – DI) during two growing cycles. Compared to ST, RV reduced soil water content during spring, inducing a significant reduction in vine vegetative growth, yield and must titratable acidity. The effects of irrigation treatments were not much pronounced. Only in the second season RDI showed a significant reduction on vine vegetative growth, yield and must titratable acidity as compared to PRD and DI whose results were similar to one another. In a dry area such as ours and a low vigor vineyard, the combination of resident vegetation with deficit irrigation treatments should be carefully considered as it can reduce yield without any benefits to grape quality. In this site the conventional deficit irrigation should be preferred to RDI and PRD as it is technically the simplest deficit irrigation strategy and has enabled an efficient control of vegetative growth without negative impact on yield and berry composition as compared to the other irrigation treatments.