Efeito da rega deficitária na fisiologia, crescimento vegetativo, produção e qualidade da uva, casta Touriga Nacional (Vitis vinifera L)

Mestrado em Viticultura e Enologia - Instituto Superior de Agronomia / Universidade do Porto. Faculdade de CiênciasThis work was carried out to compare the effects of two deficit irrigation treatments on vegetative growth, ecophysiology, yield and berry composition of the variety “Touriga Nacional”, as part of the European project “INNOVINE – Combining innovation in vineyard management and genetic for a sustainable European viticulture”(FP7/2007-2013, grant agreement nº FP7-311775). Two deficit irrigation treatments are compared: SDI (Sustainable Deficit Irrigation) corresponding to 80% evapotranspiration and RDI (Regulated Deficit Irrigation) representing 50% of the water applied in SDI. Throughout the growing season the SDI vines presented higher values of leaf water potential, photosynthesis and stomatal conductance, relatively to the RDI ones. The results indicated that the irrigation strategy influenced the physiological behavior, suggesting that in this trial the variety “Touriga Nacional” has a high control over the stomata aperture in water stress conditions. It was further observed that the vines subject to RDI exhibited better intrinsic water use efficiency throughout the season. It was found a high water stress recovery capacity from the vine in terms of photosynthesis and stomatal conductance. While the SDI treatment showed a higher leaf area than RDI, no significant differences were detected on yield. With the exception of a higher pH on SDI no other significant differences were detected on berry compositionTrabalho elaborado no âmbito do projecto INNOVINE (Combining innovation in vineyard management and genetic for a sustainable European viticulture) financiado pela União Europeia (FP7/2007-2013, grant agreement nº FP7-311775