IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 New fungus-resistant grapevine varieties display high and drought-independent thiol precursor levels

New fungus-resistant grapevine varieties display high and drought-independent thiol precursor levels

Abstract

The use of varieties tolerant to diseases is a long-term but promising option to reduce chemical input in viticulture. Several important breeding programs in Europe and abroad are starting to release a range of new hybrids performing well regarding fungi susceptibility and wine quality. Unfortunately, little attention is paid by the breeders to the adaptation of these varieties to climatic changes and to the aromatic potential such as thiol precursors. Indeed, varietal thiols (3-sulfanylhexan-ol (3SH) and its acetate or the 4-methyl-4-sulfanylpentan-2-one (4MSP)) are very powerful aromatic compounds in wines coming from odorless precursors in grapes and could contribute to the typicity of such varieties. This study aimed to characterize 6 new resistant varieties selected by INRAE (Floreal, G5 and 3159B for white grapes and Artaban, 3176N and G14 for red grapes) in comparison to Syrah to (i) quantify the thiol precursors in the fruits and to (ii) evaluate the influence of water deficit (WD) imposed on field-grown vines on these molecules. Grapes were picked-up at the arrest of phloem unloading to objectify the sampling at a precise physiological landmark and analyzed by LC-MS/MS. Six thiol precursors were quantified by isotopic dilution across all samples and only 3 were clearly identified and quantified: the glutathionylated (G3SH), cysteinylated (Cys3SH) and one dipeptidic precursors of 3SH (CysGly3SH). For all varieties, G3SH contents represented between 75 and 100% of the aromatic potential, followed by Cys3SH (0-16%) and finally the CysGly3SH (0-13%). The absolute concentrations of G3SH ranged from 31 to 132 µg/kg for white varieties and from 68 to 466 µg/kg for red ones. Surprisingly, 3176N had exceptional G3SH levels that can reach 466 µg/kg which corresponded to nearly 777 µg/L in volume concentration. The pedigree of this variety which includes Grenache as a progenitor could explain the high levels of thiol precursors as observed in the Rosé wines of Provence, a type of wines also characterized by high levels of varietal thiols. Whatever the variety, we did not find marked effects of WD on the contents in thiol precursors when expressed in µg/kg. When expressed in µg/berry to reflect the real impact of WD on rate of metabolite accumulation per organ, 3176N and Artaban showed significant differences between moderate and high WD treatments (p-value < 0.05, less amount of thiol precursors in WD grapes). Analyzing thiol precursors and more generally metabolites of interest in fruits requires to objectify the sampling date at a given physiological stage. This allows deciphering the effects of environmental factors on the accumulation of metabolites at organ or plant level and their consequences in the concentration of the fruit at harvest. In conclusion, resistant varieties seemed to be less impacted by WD than Vinifera ones, which is bode well for the development of these varieties in relation to climate change challenges.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Roland Aurélie1, Wilhelm Luciana2,3,4, Torregrosa Laurent2,3, Dournes Gabriel4, Pellegrino Anne3 and Ojeda Hernán2

1 SPO, Univ Montpellier, INRAE, Institut Agro, Montpellier, France
2 UE Pech Rouge, INRAE, Gruissan, France
3 UMR LEPSE, Montpellier Uni – CIRAD – INRAE – Institut Agro, Montpellier, France
4 UMR AGAP, Montpellier Uni – CIRAD – INRAE – Institut Agro, Montpellier, France  

Contact the author

Keywords

Climate change, water deficit, tolerant varieties, wine quality, thiol precursors

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Physiological and growth reaction of Shiraz/101-14 Mgt to row orientation and soil water status

Advanced knowledge on grapevine row orientation is required to improve establishment, management and outcomes of vineyards on terroirs with different environmental conditions (climate, soil, topography) and in view of a future change to more extreme climatic conditions. The purpose of this study was to determine the combined effect of row orientation, plant water status and ripeness level on the physiological and viticultural reaction of Shiraz/101-14 Mgt.

Effects of mechanical leafing and deficit irrigation on Cabernet Sauvignon grown in warm climate of California

San Joaquin Valley accounts for 40% of wine grape acreage and produces 70% of wine grape in California. Fruit quality is one of most important factors which impact the economical sustainability of farming wine grapes in this region. Due to the recent drought and expected labor cost increase, the wine industry is thrilled to understand how to improve fruit quality while maintaining the yield with less water and labor input. The present study aims to study the interactive effects of mechanical leafing and deficit irrigation on yield and berry compositions of Cabernet Sauvignon grown in warm climate of California.

The effects of cane girdling on berry texture properties and the concentration of some aroma compounds in three table grape cultivars

The marketability of the table grapes is highly influenced by the consumer demand; therefore the market value of the table grapes is mainly characterized by its berry size, colour, taste and texture. Girdling could cause accumulation of several components in plants above the ringing of the phloem including clusters and resulting improved maturity. The aim of the experiments was to examine the effect of girdling on berry texture characteristics and aroma concentration.

Application of a fluorescence-based method to evaluate the ripening process and quality of Pinot Blanc grape

The chemical composition of grape berries at harvest is one of the most important factors that should be considered to produce high quality wines. Among the different chemical classes which characterize the grape juice, the polyphenolic compound, such as flavonoids, contribute to the final taste and color of wines. Recently, an innovative non-destructive method, based on chlorophyll fluorescence, was developed to estimate the phenolic maturity of red grape varieties through the evaluation of anthocyanins accumulated in the berry skin. To date, only few data are available about the application of this method on white grape varieties.

Different yield regulation strategies in semi-minimal-pruned hedge (SMPH) and impact on bunch architecture

Yields in the novel viticulture training system Semi-Minimal-Pruned Hedge (SMPH) are generally higher compared to the traditional Vertical Shoot Positioning (VSP). Excessive yields have a negative impact on the vine and wine quality, which can result in substantial losses in yield in subsequent vintages (alternate bearing) or penalties in fruit quality. Therefore yield regulation is essential. The bunch architecture in SMPH differs from VSP. Generally there is a higher amount but smaller bunches with lower single berry weights in SMPH compared to VSP.