NEIKER-Tecnalia staff carried out in-depth monitoring of the vineyard, measuring the pruning weight (related to vigour), the yield and berry weight, at the grape harvest. Measurements were also taken of the shoot diameter () and the stem water potential (Ψstem) at solar midday, in order to observe the growth and water status of the vineyard. In addition, must quality parameters were also analyzed as the sugar content, total acidity, malic acid, tartaric acid and pH, as well as quality parameters related to the skin (after alcoholic fermentation of the wine): colour intensity, total polyphenol index, anthocyanins and potassium.
The results obtained (Tables 1 and 2) show that the 'flat with conventional tillage and no irrigation' treatment gave the highest values of vigour, yield and berry weight and lower values for sugar content and pH (acidity was higher), and lower levels for wine quality parameters, especially significant being the total polyphenol index. However, the 'slope with cover crop and usual irrigation' treatment showed the highest values for wine quality parameters and the lowest for productivity. In this trial, largely due to the significant topographic differences, more humidity was seen in the flat area than on the sloping area during the whole crop cycle. This is backed up by the shoot diameter and the stem water potential measurements, up to the point of registering water stress levels in the 'slope with cover crop and usual irrigation' treatment.
In general terms, it should be pointed out that, except for acidity, the parameters studied in this trial were similar for the 'slope with conventional tillage and usual irrigation' and 'flat with cover crop and no irrigation'
|Contact: Amaia Portugal|