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.

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…

Exploring high throughput secondary trait phenomics to improve grapevine breeding

Modern grapevine breeding programs have overcome many challenges using genomic selection, which has allowed breeders to make targeted selections at earlier stages in the breeding process. However, the cost of genetic testing may present a burden for some programs, and markers often struggle to accurately predict quantitative traits. Recent advances in high throughput, high-dimensional data have provoked investigation into the use of high-dimensional phenomics as a low-cost addition to the grape breeder’s toolkit that may offer advantages in predicting quantitative traits. High-dimensional secondary trait (HDST) data has been employed in annual crops for prediction of agriculturally important traits such as yield.

MAPPING OF GAS-PHASE CO₂ IN THE HEADSPACE OF CHAMPAGNE GLASSES BY USING AN INFRARED LASER SENSOR UNDER STATIC TASTING CONDITIONS

From the chemical angle, Champagne wines are complex hydro-alcoholic mixtures supersaturated with dissolved carbon dioxide (CO₂). During the pouring process and throughout the several minutes of tasting, the headspace of a champagne glass is progressively invaded by many chemical species, including gas-phase CO₂ in large majority. CO₂ bubbles nucleated in the glass and collapsing at the champagne surface act indeed as a continuous paternoster lift for aromas throughout champagne or sparkling wine tasting [1]. Nevertheless, inhaling a gas space with a concentration of gaseous CO₂ close to 30% and higher triggers a very unpleasant tingling sensation, the so-called “carbonic bite”, which might completely perturb the perception of the wine’s bouquet.

CHARACTERIZATION AND ANTIBACTERIAL ACTIVITY OF A POLYPHENOLIC EXTRACT OBTAINED BY GREEN SUPERCRITICAL CO₂ EXTRACTION FROM RED GRAPE POMACE

Upgrading wine industry solid wastes is considered as one of the main strategies to support the circular economy. Red grape pomaces constitute a rich source of polyphenols, which have been shown to possess antioxidant properties and to provide benefits for human and animal health. The objective of this work was to obtain and characterise polyphenolic extracts from red grape pomaces via green supercritical CO₂ extraction using ethanol as a co-solvent, and to evaluate their antibacterial activity against susceptible and multidrug-resistant Escherichia coli strains of animal intestinal origin.

Identification of the agronomical and landscape potentialities in Côtes du Rhône area (France)

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...

Modelling vine water stress during a critical period and potential yield reduction rate in European wine regions: a retrospective analysis

Most European vineyards are managed under rainfed conditions, where seasonal water deficit has become increasingly important. The flowering-veraison phenophase represents an important period for vine response to water stress, which is seldomly thoroughly evaluated. Therefore, we aim to quantify the flowering-veraison water stress levels using Crop Water Stress Indicator (CWSI) over 1986–2015 for important European wine regions, and to assess the respective potential Yield Lose Rate (YLR). Additionally, we also investigate whether an advanced flowering-veraison phase may help alleviating the water stress with improved yield. A process-based grapevine model STICS is employed, which has been extensively calibrated for flowering and veraison stages using observed data at 38 locations with 10 different grapevine varieties. Subsequently, the model is being implemented at the regional level, considering site-specific calibration results and gridded climate and soil datasets. The findings suggest wine regions with stronger flowering-veraison CWSI tend to have higher potential YLR. However, contrasting patterns are found between wine regions in France-Germany-Luxembourg and Italy-Portugal-Spain. The former tends to have slight-to-moderate drought conditions (CWSI<0.5) and a negligible-to-moderate YLR (<30%), whereas the latter possesses severe-to-extreme CWSI (>0.5) and substantial YLR (>40%). Wine regions prone to a high drought risk (CWSI>0.75) are also identified, which are concentrated in southern Mediterranean Europe. An advanced flowering-veraison phase may have benefited from cooler temperatures and a higher fraction of spring precipitation in wine regions of Italy-Portugal-Spain, resulting in alleviated CWSI and moderate reductions of YLR. For those of France-Germany-Luxembourg, this can have reduced flowering-veraison precipitation, but prevalent alleviations of YLR are also found, possibly because of shifted phase towards a cooler growing season with reduced evaporative demands. Overall, such a retrospective analysis might provide new insights towards better management of seasonal water deficit for conventionally vulnerable Mediterranean wine regions, but also for relatively cooler and wetter Central European regions.