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…

‘Cabernet Sauvignon’ (Vitis vinifera L.) berry skin flavonol and anthocyanin composition is affected by trellis systems and applied water amounts

Trellis systems are selected in wine grape vineyards to mainly maximize vineyard yield and maintain berry quality. This study was conducted in 2020 and 2021 to evaluate six commonly utilized trellis systems including a vertical shoot positioning (VSP), two relaxed VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a guyot (GY), combined with three levels of irrigation regimes based on different crop evapotranspiration (ETc) replacements, including a 25% ETc, 50% ETc, and 100% ETc. The results indicated SH yielded the most fruits and accumulated the most total soluble solids (TSS) at harvest in 2020, however, it showed the lowest TSS in the second season. In 2020, SH and HQ showed higher concentrations in most of the anthocyanin derivatives compared to the VSPs. Similar comparisons were noticed in 2021 as well. SH and HQ also accumulated more flavonols in both years compared to other trellis systems. Overall, this study provides information on the efficacy of trellis systems on grapevine yield and berry flavonoid accumulation in a currently warming climate.

First step in the preparation of a soil map of the Protected Designation of Origin Valdepeñas (Central, Spain)

This work is a first step to make a map of vineyard soils. The characterization of the soils of the Protected Designation of Origin (D.P.O.) Valdepeñas will allow to group the studied profiles according to their physico-chemical characteristics and the concentrations of most relevant chemical elements. 90 soil profiles were analysed throughout the territory and the soils were sampled and described according to FAO (2006) and classified according to and Soil Taxonomy (2014). All samples were air dried, sieved and some physico-chemical parameters were determined following standard protocols. Also, major and trace elements were analysed by X-ray fluorescence. The statistically study was made using the SPSS program. Trend maps were made using the ArcGIS program. The studied soils have the following average properties: pH, 8.3; electrical conductivity, 0,20 dS/m (low); clay, 18.8% (medium) and CaCO3, 17.1% (high). In the study for the major elements. The major elements of these soils are Si, followed by Ca and Al, with an average content of 203.7 g/kg, 105.5 g/kg and 74.0 g/kg respectively. On the other hand, 27 trace elements have been studied. Of all of them, it can be highlighted the average values of Ba (361.8 mg/kg), Sr (129.3 mg/kg), Rb (83.4 mg/kg), V (74.2 mg/kg) and Ce (70.6 mg/kg). Ba, V and Ce values are higher and the values of Sr and Rb are lower to those found in the literature. The discriminant analysis shows a percentage of grouping of 91%. The content of chemical elements together with the physico-chemical characteristics allows grouping the soils in 4 group according to their order in the classification to Soil Taxonomy; due to the importance of the Calcisols in Castilla-La Mancha, it has been decided to establish them as their own group even if they do not appear in Soil Taxonomy classification.

Extreme canopy management for vineyard adaptation to climate change: is it a good idea?

Climate change constitutes an enormous challenge for humankind and for all human activities, viticulture not being an exception. Long-term strategic changes are probably needed the most, but growers also need to deal with short-term changes: summers that are getting progressively warmer, earlier harvest dates and higher pH in musts and wines. In the last 10-15 years, a relevant corpus of research is being developed worldwide in order to evaluate to which extent extreme canopy management operations, aimed at reducing leaf area and, thus, limiting the source to sink ratio, could be useful to delay ripening. Although extreme canopy management can result in relevant delays in harvest dates, longer term studies, as well as detailed analysis of their implications on carbohydrate reserves, bud fertility and future yield are desirable before these practices can be recommended.

Analysis of some environmental factors and cultural practices that affect the production and quality of the Manto Negro, Callet and Prensal Blanc varieties

45 non irrigated vineyards distributed in the DO (Denomination) Pla i Llevant de Mallorca and the DO Binissalem Mallorca were used to investigate the characteristics of production and quality and their relationships certain environmental factors and cultural practices. The grape varieties investigated are autochthonous to the island of Mallorca, Manto Negro and Callet as red and Prensal Blanc as white. All plants were measured for four consecutive years in the main production and quality parameters. Among the environmental factors, the type of soil has been studied, more specifically its water retention capacity, the planting density, the age of the vineyard and the level of viral infection. The presence or absence of virus seems to have no effect on any component studied in the varieties studied. For the white variety Prensal Blanc age is negatively correlated with production and the number of bunches, nevertheless it does not cause any effect on the required quality parameters. However, for the red varieties Callet and Manto Negro, the age of the plantation is the variable that best correlates with the quality parameters, therefore the old vines should be the object of preservation by the viticulturists and winemakers in order to guarantee its contribution to the quality of the wines made with these varieties.

Grape berry size is a key factor in determining New Zealand Pinot noir wine composition

Making high quality but affordable Pinot noir (PN) wine is challenging in most terroirs and New Zealand’s (NZ) situation is no exception. To increase the probability of making highly typical PN wines producers choose to grow grapes in cool climates on lower fertility soils while adopting labour intensive practices. Stringent yield targets and higher input costs necessarily mean that PN wine cost is high, and profitability lower, in line-priced varietal wine ranges. To understand the reasons why higher yielding vines are perceived to produce wines of lower quality we have undertaken an extensive study of PN in NZ. Since 2018, we established a network of twelve trial sites in three NZ regions to find individual vines that produced acceptable commercial yields (above 2.5kg per vine) and wines of composition comparable to “Icon” labels. Approximately 20% of 660 grape lots (N = 135) were selected from within a narrow juice Total Soluble Solids (TSS) range and made into single vine wines under controlled conditions. Principal Component Analysis of the vine, berry, juice and wine parameters from three vintages found grape berry mass to be most effective clustering variable. As berry mass category decreased there was a systematic increase in the probability of higher berry red colour and total phenolics with a parallel increase in wine phenolics, changed aroma fraction and decreased juice amino acids. The influence of berry size on wine composition would appear stronger than the individual effects of vintage, region, vineyard or vine yield. Our observations support the hypothesis that it is possible to produce PN wines that fall within an “Icon” benchmark composition range at yields above 2.5kg per vine provided that the Leaf Area:Fruit Weight ratio is above 12cm2 per g, mean berry mass is below 1.2g and juice TSS is above 22°Brix.