terclim by ICS banner
IVES 9 IVES Conference Series 9 Impact of canopy management on thiol precursors in white grapes: a six-year field study

Impact of canopy management on thiol precursors in white grapes: a six-year field study

Abstract

The mechanisms behind thiol precursor accumulation in grapes remain incompletely understood, nor are the ways in which they can be improved by agronomic practices. A six-year field trial studied the physiological response of the Swiss white cultivar Vitis vinifera Arvine, rich in varietal thiols and precursors, to canopy management, i.e. leaf removal and canopy height.. Five treatments were set up in a randomized block design to assess the impacts of 1) pre-flowering LR (i.e. pre-flowering or full-flowering stages) and 2) compensating for the leaf area removed in the cluster zone by increasing the trimming height (i.e. 100 or 150 cm canopy height), compared with a non-defoliated control treatment.

Intensive pre-flowering LR severely reduced yield potential (–47% on average) and reduced the concentration of 3-mercaptohexanol precursors (P-3MH) in the must (–21%; p-value < 0.10). Decreasing earliness modulated the impact of LR on yield (–12%) and P-3MH concentration (–6%). Compensating for suppressed leaf area by increasing the trimming height slightly enhanced grape ripening (+1% total sugars; –3% titratable acidity), slightly improved the overall quality of the wine (color intensity, volume), while having no impact on must P-3MH concentration or on wine bouquet.

Observing the long-term impact of each LR treatment separately provided insights into the physiological mechanisms influencing fruit development and aroma formation. This trial is part of a larger project on canopy management and its impact on grape composition in temperate Swiss climatic conditions.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Thibaut Verdenal1*, Vivian Zufferey1, Ágnes Dienes-Nagy2, Gilles Bourdin2, Jean-Laurent Spring1

1 Agroscope, avenue Rochettaz 21, 1009 Pully, Switzerland
2 Agroscope, route de Duillier 60, case postale 1012, 1260 Nyon 1, Switzerland

Contact the author*

Keywords

leaf removal, canopy height, 3-mercaptohexanol, grapevine, wine aroma

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

New acylated flavonols identified in the grape skin of Vitis vinifera cv. Tannat and their wines

Flavonols are a class of flavonoid compounds derived from plant secondary metabolism. There they play different roles like antioxidants, internal regulators and UV screenings. In red wines, flavonols have increasingly received consideration by part of scientific and winemakers according their properties began to arise known. Among these stand out wine colour stabilization and their value as bioactive compounds. In this work the complete series of the acetylated and p-coumaroylated derivatives of the 3-O-glycosides of methoxylated flavonols, namely isorhamnetin, laricitrin and syringetin, have been identified in grapes and their respective wines from Vitis vinifera cv. Tannat.

Impact of temperature and solar radiation on grape composition variability in the Saint-Emilion winegrowing area 

Grape composition is strongly influenced by climate conditions. Their expected modifications in near future, notably because of increased temperatures, could significantly modify the biochemical composition of berries at harvest, and thus wine typicity and quality. Elevated temperatures favor sugar accumulation in grapes, enhance malic acid degradation and modify the amino acid content. They also reduce significantly anthocyanin accumulation in Merlot, leading to the imbalance between anthocyanins and sugars, while no significant effects on final anthocyanin levels were reported in Tempranillo[1] and finally affect aromas or aroma precursors.

Oenological potential of cv. Tortojona: A minority grape variety from Extremadura, southwest Spain

This work, included in the VAVEGEX project, aims to evaluate the oenological, phenolic, chromatic and sensory characteristics of the grapes, must and wines produced from cv. Tortojona, minority variety grown in Extremadura region (Southwest, Spain).

Possible methods of adaptation to the effects of climate change in the Tokaj Wine Region 

Viticulture’s adaptation to the harmful effects of climate change is globally the biggest challenge of the near future. Short, extremely intensive rainfalls and longer periods of drought are getting more frequent in the Tokaj Wine Region, where the majority of the vineyards are cultivated on steep slopes. Hence, erosion has high risk, especially when combined with the loess-based soils on about ten percent of the region. The environmentally beneficial cover crop and mulch usage can effectively reduce the risk of erosion, according to research done by the Tokaj Wine Region Research Institute of Viticulture and Oenology.

Association between dietary pattern and wine consumption and Alzheimer’s disease in a cohort from La Rioja (Spain)

Addressing modifiable risk factors is the most promising strategy to prevent/delay Alzheimer Disease (AD)[1]. The aim of the study was to establish the connections between dietetic habits, wine consumption and AD. Thus, 98 volunteers were recruited: 50 diagnosed as AD and 48 healthy/controls. The Food Frequency Questionnaire (FFQ) was used for dietary patterns assessment and, based on these data, the Mind Diet Score was calculated. (Poly)phenol metabolites (especially derived from wine consumption) were analyzed by UPLC-QqQ-MS/MS in 24-h urine samples to confirm dietary (poly)phenol consumption.