terclim by ICS banner
IVES 9 IVES Conference Series 9 Second pruning as a strategy to delay maturation in cv. ‘Touriga nacional’ in the Portuguese Douro region

Second pruning as a strategy to delay maturation in cv. ‘Touriga nacional’ in the Portuguese Douro region

Abstract

The advance in maturation of wine grapes is an important climate change risk related effect that could affect warm regions like Portuguese Douro Wine Region. Indeed, the climate analysis over the past years registered a decrease in the precipitation, significant higher average temperatures, and a more frequent occurrence of extreme weather events, including heat waves. In these conditions the length from anthesis until maturation is shortened and the uncoupling of technical and phenolic maturity results in berries with higher sugar concentration (and lower acidity), but lower anthocyanins, tannins, and total phenolic concentration, which produce unbalanced wines.
In this work, an innovative strategy of crop forcing, based on forcing vine regrowth after a second pruning of green shoots, was tested, aimed at delaying ripening until the temperature becomes lower and, therefore, preventing acidity loss and increasing anthocyanin-to-sugar ratio. The experiments were conducted in 2019 and 2020 in a commercial vineyard of ‘Touriga Nacional’ located in the Douro Region. Crop forcing was conducted 15 (CF1) to 30 (CF2) days after fruit set. Vines pruned with conventional methods were used as control (CF0). Results confirmed that fruit ripening was shifted from the hot season (August/September), until a cooler period (October through early-November). At harvest, grapevine berries from CF1 and CF2 presented lower pH and higher acidity, than control, with no significant differences in colour intensity and phenolic levels composition. Sugar content was lower in CF2-treated vines in both seasons. However, in CF-treated vines the number and size of clusters were significantly lower (up to 88% reduction) than in control plants. A metabolomics analysis of mature berries from CF-treated vines and control is underway. Crop forcing was indeed effective in producing a more balance berry composition but severely reduced grapevine yield,

 

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Poster

Authors

Inês L. Cabral1, António Teixeira3, Joana Valente2, Fernando Alves2, Frank S. Rogerson2, Susana M.P. Carvalho1, Hernâni Gerós3 and Jorge Queiroz1

1GreenUPorto – Sustainable Agrifood Production Research Centre / Inov4Agro, DGAOT, Faculty of Sciences of University of Porto, Vairão, Portugal
2Symington Family Estates, Vila Nova de Gaia, Portugal
3Centre of Biological Engineering (CEB), Department of Biological Engineering, Centre of Molecular and Environmental Biology, Department of Biology University of Minho, Braga, Portugal

Contact the author

Keywords

berry composition, climate change, fruit ripening, grapevine, yield

Tags

IVES Conference Series | Terclim 2022

Citation

Related articles…

Assessing the climate change vulnerability of European winegrowing regions by combining exposure, sensitivity and adaptive capacity indicators

Winegrowing regions recognized as protected designations of origin (PDOs) are closely tied to well defined geographic locations with a specific set of pedoclimatic attributes and strictly regulated by legal specifications. However, climate change is increasingly threatening these regions by changing local conditions and altering winegrowing processes. The vulnerability to these changes is largely heterogenous across different winegrowing regions because it is determined by individual characteristics of each region, including the capacity to adapt to new climatic conditions and the sensitivity to climate change, which depend not only on natural, but also socioeconomic and legal factors. Accurate vulnerability assessments therefore need to combine information about adaptive capacity and climate change sensitivity with projected exposure to new climatic conditions. However, most existing studies focus on specific impacts neglecting important interactions between the different factors that determine climate change vulnerability. Here, we present the first comprehensive vulnerability assessment of European wine PDOs that spatially combines multiple indicators of adaptive capacity and climate change sensitivity with high-resolution climate projections. We found that the climate change vulnerability of PDO areas largely depends on the complex interactions between physical and socioeconomic factors. Homogenous topographic conditions and a narrow varietal spectrum increase climate change vulnerability, while the skills and education of farmers, together with a good economic situation, decrease their vulnerability. Assessments of climate change consequences therefore need to consider multiple variables as well as their interrelations to provide a comprehensive understanding of the expected impacts of climate change on European PDOs. Our results provide the first vulnerability assessment for European winegrowing regions at high spatiotemporal resolution that includes multiple factors related to climate exposure, sensitivity, and adaptive capacity on the level of single winegrowing regions. They will therefore help to identify hot spots of climate change vulnerability among European PDOs and efficiently direct adaptation strategies.

Are biochemical markers the key to predicting wine aroma balance?

Wine aroma quality is a complex interplay of factors like terroir, vinification techniques, that modulate aroma compound composition.

Do wine sulphites affect gut microbiota? An in vitro study of their digestion in the gastrointestinal tract

“Sulphites” and mainly sulphur dioxide (SO2) is by far the most widely used additive (E-220/INS 220) in winemaking and likely the most difficult to replace. The well-known antioxidant, antioxidasic and antimicrobial properties of SO2 make this molecule a practically essential tool, not only in winemaking, but also in the production of other food products. The current trend in winemaking is the reduction of this unfriendly additive due to its negative effects on health and environmental. In particular, it could cause headaches and intolerance/allergic reactions in sensitive individuals. Wine is considered one of the major contributors of exposure of SO2 in the adult population, when this beverage is included in the diet.

Sorption of aroma compounds by commercial specific yeast derivatives and the influence of polyphenols

Specific inactivated yeast derivatives (SYDs) from S. cerevisiae are obtained through thermal, mechanical, and enzymatic processes and are used to enhance wine quality.

EXPLORING THE METABOLIC AND PHENOTYPIC DIVERSITY OF INDIGENOUS YEASTS ISOLATED FROM GREEK WINE

Climate change leads to even more hostile and stressful for the wine microorganism conditions and consequently issues with fermentation rate progression and off-character formation are frequently observed. The objective of the current research was to classify a great collection of yeast isolates from Greek wines based on their technological properties with oenological interest. Towards this direction, fourteen spontaneously fermented wines from different regions of Greece were collected for further yeast typing. The yeast isolates were subjected in molecular analyses and identification at species level.