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IVES 9 IVES Conference Series 9 CLIMATE CHANGE EFFECT ON POLYPHENOLS OF GRIGNOLINO GRAPES (VITIS VINIFERA L.) IN HILLY ENVIRONMENT

CLIMATE CHANGE EFFECT ON POLYPHENOLS OF GRIGNOLINO GRAPES (VITIS VINIFERA L.) IN HILLY ENVIRONMENT

Abstract

Current changes of ecoclimatic indicators may cause significant variation in grapevine phenology and grape ripening. Climate change modifies several abiotic factors (e.g. temperature, sunlight radiation, water availability) during the grapevine growth cycle, having a direct impact on the phenological stages of the grapevine, modulating the metabolic profile of berries and activating the synthesis and accumulation of diverse compounds in the skin of berries, with consequences on the composition of the grapes.

The influence exerted by different meteorological conditions, during three consecutive years (2020-2022) on secondary metabolites such as the polyphenolic profile of Grignolino grapes was investigated. The samples were collected from three vineyards characterized by different microclimatic conditions mainly related to the vineyard aspect and to a different age of the plants.

Significant variations were observed in temperature and rainfall patterns among the different vintage years. The response of grape secondary metabolism to abiotic stress, with particular emphasis on polyphenolic profile of the berries was evaluated using spectrophotometry and HPLC.

The results highlighted significant differences among the vintages for each vineyard as to the berry weight and the contents of the several classes of polyphenols. 2022 Vintage distinguished by a series of extreme conditions in terms of high temperature and low rainfall, showed low berry weight and skin contents of almost all polyphenols, especially for the southwest exposed vineyards. The seeds, on the other hand, exhibited higher amounts of polyphenols, possibly due to their greater extractability. Berry weight being equal, fresh conditions during the green phase until veraison, followed by dry and hot pre harvest period privileged phenolics mainly in the berries of the southeast vineyard. Younger vineyard showed more result variability through the years.

The intensity and mainly the timing of meteorological fluctuations affected the final content in phenolics of Grignolino grapes. In hilly environment, conditions of limited water availability and high temperature, that lately are characterizing the second part of berry development, seem to support the grape quality of Grignolino, a cultivar of medium-late ripening, by limiting the differences on bunch ripening, allowing a greater accumulation of secondary metabolites, but maintaining at the same time an optimum balance sugar/acidity.

 

1. Bagagiolo, G., Rabino, D., Biddoccu, M., Nigrelli, G., Berro, D. C., Mercalli, L., et al. (2021). Effects of inter-annual climate variability on grape harvest timing in rainfed hilly vineyards of Piedmont (NW Italy). Italian Journal of Agrometeorology, 37–49. 
2. Rienth, M., Vigneron, N., Darriet, P., Sweetman, C., Burbidge, C., Bonghi, C., et al. (2021). Grape berry secondary metabolites and their modulation by abiotic factors in a climate change scenario–a review. Frontiers in Plant Science 12, 262.
3. van Leeuwen, C., and Darriet, P. (2016). The impact of climate change on viticulture and wine quality. Journal of Wine Eco-nomics 11, 150–167.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Maurizio Petrozziello1, Federica Bonello1, Mario Ronco2,3, Andriani Asproudi1*

1. CREA – CREA-VE: Council for Agricultural Research and Economics- Research centre for Viticulture and Enology. Via P. Micca 35, 14100 Asti, Italy.
2. Associazione Monferace, Castello di Ponzano Monferrato, Piazza Vittorio Veneto 1, Ponzano Monferrato – 15022 Alessan-dria, Italy.
3. Wine consulting Mario Ronco, Piazza Stazione 25, Moncalvo – 14036 Asti, Italy.

Contact the author*

Keywords

meteorological conditions, vineyards age, vineyard aspect, grape polyphenols

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

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