Influence of cover crops in a Tempranillo vineyard grown under the edaphoclimatic conditions of the Appellation of Origin Rueda

The way to manage the vineyard soils has certainly changed in Spain during the last years. Traditionally, the vineyards were tilled, but this growing technique has been replaced in some vineyards by the bare soil with herbicide. Also, soil cover crops have started to be applied in some vineyards. The competition between the roots systems of the vines and the cover crop can influence on the capacity and the conditions of the plants for water absorption, transport of photosynthesized products to the roots, etc. Consequently, the cover crop can affect the water supply to the vine. The objective of this trial has been to study the behaviour of the Tempranillo variety under different alternatives of soil management, analysing the vegetative-productive vine balance and its influence on the grape quality, as well as the soil water content and the dry matter produced by the cover crop species. The trial has been carried out along 2006 and 2007 on a Tempranillo/110R vineyard, vertical trellis trained with Royat cordon pruning, with 3.00 m x 1.25 m vine spacing. The soil has homogeneus sandy-loam structure from the surface to the 110 cm depth, where there is a ground water table. The experimental treatments have been the following: TIL, traditional tillage (2006 and 2007); BAR, barley (Hordeum vulgare) (2006 and 2007); LEG, Vicia monanthos (2006) and vetch (Vicia sativa) (2007); PER, resident vegetation (2006) and or perennial vegetation, fescue (Festuca orundinacea) and ryegrass (Lolium perenne) combination at 50% (2007). The use of cover crop species in the inter-row space has provoked highly significant differences among treatments in yield, depending on the cover crop species and the annual climatic conditions. Legume and perennial species have shown to be more water competitive towards the vines than the rest of cover crops applied, which has reduced yield and vegetative development and has increased the dry matter produced by this species with respect to the others. The influence of the soil management on grape quality has not been determinant, in such a way that it has depended on the annual conditions and the level of yield, as well as on the cover crop species