GiESCO 2019 banner
IVES 9 IVES Conference Series 9 GiESCO 9 GiESCO 2019 9 Climate change 9 Changes in flavonol profile are a reliable indicator to assess the exposure of red grape berries to solar radiation and canopy architecture

Changes in flavonol profile are a reliable indicator to assess the exposure of red grape berries to solar radiation and canopy architecture

Abstract

Context and purpose of the study ‐ Exposure to solar radiation affects berry composition through photomorphogenesis or changes in temperature. Flavonol synthesis is upregulated by UV‐B radiation leaving a fingerprint on flavonol profile. This study aimed to test the factors affecting flavonol accumulation and profile and their potential as an indicator to assess the overall exposure of red wine grape berry to solar radiation.

Material and methods ‐ We performed three experiments to study the response of flavonol accumulation and profile to (1) three different solar radiation exclusion treatments (shading nets) during berry development; (2) canopy porosity and leaf area index (LAI); and (3) natural variability of vine vigour and canopy management practices.

Results ‐ Results showed a strong relationship between global radiation, inverse dormant pruning weights or canopy porosity (inversely proportional to LAI) and % kaempferol or % quercetin. Furthermore, the increase in concentration of the above two flavonols was associated with a reduction of % myricetin. Total flavonol content, % kaempferol, % quercetin and % myricetin had significant correlations with inverse dormant pruning weights, but these were less sensitive to over‐ripening or water deficits. Flavonol profile was associated to site hydrology (wetness index) through changes in vigour, and to LAI; and responded to shoot thinning or fruit‐zone leaf removal. Flavonol profile was also correlated to the maximal temperature reached by the clusters. These results support the reliability of the flavonol profile as an assessment parameter for studies aiming to discuss canopy architecture or the effect of solar radiation on grapevine berries.

Download the PDF

DOI:

Publication date: June 19, 2020

Issue: GiESCO 2019

Type: Article

Authors

Johann MARTÍNEZ‐LÜSCHER (1), Luca BRILLANTE (2,3), S. Kaan KURTURAL (1)

(1) Department of Viticulture and Enology University of California, Davis, U.S.A.
(2) Department of Viticulture and Enology California State University, Fresno, U.S.A.

Contact the author

Keywords

flavonoids, solar radiation, temperature, fruit ripening, grape composition, precision agriculture, UV‐B radiation

Tags

GiESCO 2019 | IVES Conference Series

Citation

Related articles…

White grape must processed by UHPH as an alternative to SO2 addition: Effect on the phenolic composition in three varieties

The quantity and distribution of polyphenols in musts play a fundamental role in the white winemaking. This is because these substances are exposed to oxidation reactions, which are catalysed by the polyphenol oxidase (PPO), leading to a decrease in the quality of the wines produced. PPO is inactivated by SO2, but currently, due to the restrictions of the legislation, other methodologies are being investigated. Ultra-High Pressure Homogenization (UHPH) is a non-thermal physic technology that exerts an ultrahigh pressure pumping (>200 MPa) of a fluid through a valve in a continuous system.

Read More

Traçability of main mineral elements on the chain “soil-leaf-must-wine” in relation to “terroir” and vintage in Loire Valley(France)

Dans le cadre de recherches sur la mise en évidence et le déterminisme d’un «effet terroir »un réseau de parcelles du cépage Cabernet Franc greffé sur S04, a été suivi de 1979 à 1990 en Val de Loire (A.O.C. Saumur-Champigny, Chinon et Bourgueil). Des analyses chimiques (N,P, K, Ca, Mg, Fe, Mn, Zn) ont été réalisées sur le sol, les feuilles au stade véraison, les moûts en cours de maturation et à la vendange et enfin sur le vin, pour 18 sites (répartis dans 12unités terroirs de base) et 7 millésimes différents.

Read More

La hiérarchisation des Coteaux du Languedoc: une application concrète du zonage vitivinicole

L’A.O.C. Coteaux du Languedoc est située dans le Sud de la France, dans la partie Ouest de la bordure méditerranéenne. Elle forme un vaste amphithéâtre largement ouvert sur la mer méditerranée. L’Appellation a été constituée en 1960 par le regroupement de 14 anciennes petites appellations d’origine représentant 55 communes éparpillées dans les départements de l’Aude, de l’Hérault et du Gard. Par la suite, plusieurs extensions successives ont conduit à un ensemble actuellement composé de 168 communes.

Read More

Quantitative assessment of must composition using benchtop NMR spectroscopy: comparative evaluation with FTIR and validation by reference

The foundation of wine production lies in the use of high-quality grapes. To produce wines that meet the highest standards, a fast and reliable analytical assessment of grape quality is essential. Many wineries currently employ Fourier-Transform Middle-Infrared Spectroscopy (FTIR) for this purpose.

Read More

Grape solids: new advances on the understanding of their role in enological alcoholic fermentation

Residual grape solids (suspended particles) in white and rosé musts vary depending on the clarification pro-cess. These suspended solids contain lipids (more especially phytosterols) that are essential for yeast meta-bolism and viability during fermentation in anaerobic conditions.

Read More