terclim by ICS banner
IVES 9 IVES Conference Series 9 GiESCO 9 Cumulative effect (6 years) of deficit irrigation in two important cultivars of Douro region, Portugal

Cumulative effect (6 years) of deficit irrigation in two important cultivars of Douro region, Portugal


Context and purpose of the study – Numerous studies have demonstrated the importance of irrigation in improving the grape yield and quality in areas with arid and semiarid climates, particularly in the context of ongoing climate changes. However, the introduction of irrigation in vineyards of the Mediterranean basin is a matter of debate, in particular in those of the Douro Demarcated Region (DDR), due to the limited number of available studies in this region. The present study aimed to evaluate how different irrigation deficits for 6 years would influence production and must quality in Touriga Francesa (TF) and Touriga Nacional (TN) varieties.

Material and methods – Field grown plants of cultivars TF and TN, were tested in a commercial vineyard, at Douro Superior sub-region, between 2015 and 2020. Vineyards are planted in a steep slope area (slope of 45%), in terraces of two rows, in a schistic and acidic soil. Three irrigation regimes were compared to a rain-fed treatment, R0, based on the estimated crop evapotranspiration (ETc): R25 (25% ETc), R50 (50% ETc), R75 (75% ETc). Irrigation was performed every 15 days, based on weather parameters recorded at the meteorological station located in the plot.

Results – Regarding the production, the number of clusters/vine in TN at different irrigation debts were as follows: R0 = R25 = R50 < R75 (11% higher). In turn, the yield was as follows: R75 > R0/R50 > R25.  In TF variety, the lowest number of clusters/vine was registered at R0 (24% lower than at R75), and the yield at all irrigation debts were higher than at R0. Considering the composition of the must of both varieties, evaluated during the six years of the trial, results showed that all irrigation debts did not change the sugar amount, pH and acidity (titratable and malic acid), nor phenolic compounds. In TN, values of pruning mass were higher at R75, while in TF the pruning mass was higher at R50. These results showed that irrigation in DDR did not significantly change berry quality traits and its effect in vine performance was inconsistent, thus suggesting that this agricultural practice should be implemented in a case-by-case scenario, depending on the cultivar, orientation, water holding capacity of the soil, microclimatic conditions, among others.


Publication date: June 21, 2023

Issue: GiESCO 2023

Type: Article


Inês L. CABRAL1, António TEIXEIRA2, Tiago NOGUEIRA3, Susana M.P. CARVALHO1, Hernâni GERÓS2, Jorge QUEIROZ1*

1GreenUPorto – Research Centre on Sustainable Agrifood Production/Inov4Agro & DGAOT, Faculty of Sciences, Campus de Vairão, University of Porto, Rua da Agrária 747, 4485-646 Vairão, Portugal
2Centre of Molecular and Environmental Biology (CBMA), Department of Biology, Campus de Gualtar, University of Minho, 4710-057 Braga, Portugal
3Quinta do Crasto, S.A., 5060-063 Gouvinhas, Portugal

Contact the author*


climate change, evapotranspiration, grapevine, must composition, yield


GiESCO | GIESCO 2023 | IVES Conference Series


Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.