IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Climate change, regional adaptation necessities and impact on grape and wine composition – an integrated view on a moving target

Climate change, regional adaptation necessities and impact on grape and wine composition – an integrated view on a moving target

Abstract

Grapevines are cultivated on 6 out of 7 continents, roughly between latitudes 4° and 56° in the Northern Hemisphere and between 6° and 42° in the Southern Hemisphere across a large diversity of climates (oceanic, warm oceanic, transition temperate, continental, cold continental, Mediterranean, subtropical, attenuated tropical, and arid climates). Accordingly, the range and magnitude of environmental factors differ considerably from region to region and so do the principal environmental constraints for grape production. Due to climate change, temperature, as the primary factor limiting the suitability for wine production is changing causing shifts in the regional distribution of wine producing areas and bringing “new” cool climate producers to the map and may be putting warmer areas at risk. 

The recent publication of the IPCC report (2021, 2022) will be analysed with respect to regional projections relevant for Viticulture and Oenology across the northern and southern hemisphere. The presentation will examine the climate development of various regions across cooler and warmer grape growing areas, and the potential impact on varietal distribution. As a second major environmental factor, water availability is a constraint in many grape growing areas. But projected changes in precipitation (P) rates are only one part of the equation. Since the water cycle is coupled to temperature because temperature plays a large role in the evaporation of water from surfaces or the transpiration of water through plants (ETp), it is the balance between P and ETp which determines water availability and this balance is changing in different directions in various grape growing regions. 

Both temperature and water availability have known effects on fruit composition. Much more difficult to quantify are effects through, for instance, changes in soils. We observe rising temperatures in the upper soil layers in access to the warming observed for air temperature. This will have an impact on the distribution of microbial populations, the decay rate of organic matter, the supply with nutrients, or the storage capacity for soil organic carbon (SOC), thus affecting the emission of greenhouse gases (GHGs) and the viscosity of water in the soil-plant pathway, altering the transport of water. Interactions between micro-organisms in the rhizosphere, the grapevine root system, degradation and fixation of SOC are complex and poorly understood but respond to environmental factors (such as increased soil temperatures), the plant material (rootstock for instance), respectively the cultivation system (for example bio-organic versus conventional, cover crop use versus open tillage for example). 

It is one of the major challenges in projecting analytical changes in the fruit and wine induced by these complex changes of a viticultural system through climate change aside of the main components sugar and acidity. The rising ambient CO2-concentration itself will also contribute to changes in leaf and fruit biochemistry and the interaction with the environmental factors temperature and water may act synergistically or antagonistically, exacerbating or mitigating effects

DOI:

Publication date: June 22, 2022

Issue: IVAS 2022

Type: Article

Authors

Hans Reiner Schultz¹*

¹Hochschule Geisenheim University, von-Lade-Straße 1, D-65366 Geisenheim, Germany

Hans Reiner Schultz¹*

¹Hochschule Geisenheim University, von-Lade-Straße 1, D-65366 Geisenheim, Germany

Contact the author

Keywords

climate change and regional impacts, regulation programs, adaptation strategies, grape and wine composition 

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Phenolic extraction during fermentation as affected by ripeness level of Syrah/R99 grapes

L’extraction phénolique au cours de la fermentation à partir de vendanges de différents degrees de maturité du cépage Syrah/R99 a été etudiée. Cette travail fait parti d’un projet focalisé sur la qualité du raisin et des vins obtenus au cours du millésime 2002. Les vignes sont situées à Stellenbosch (Afrique du Sud) sur un sol Glenrose

Delaying irrigation initiation linearly reduces yield with little impact on maturity in Pinot noir

When to initiate irrigation is a critical annual management decision that has cascading effects on grapevine productivity and wine quality in the context of climate change. A multi-site trial was begun in 2021 to optimize irrigation initiation timing using midday stem water potential (ψstem) thresholds characterized as departures from non-stressed baseline ψstemvalues (Δψstem). Plant material, vine and row spacing, and trellising systems were concomitant among sites, while vine age, soil type, and pruning systems varied. Five target Δψstem thresholds were arranged in an RCBD and replicated eight times at each site: 0.2, 0.4, 0.6, 0.8, and 1.0 MPa (T1, T2, T3, T4, and T5, respectively). When thresholds were reached, plots were irrigated weekly at 70% ETc. Yield components and berry composition were quantified at harvest. To better generalize inferences across sites, data were analyzed by ANOVA using a mixed model including site as a random factor. Across sites, irrigation was initiated at Δψstem = 0.24, 0.50, 0.65, 0.93, and 0.98 MPa for T1, T2, T3, T4, and T5, respectively. Consistent significant negative linear trends were found for several key yield and berry composition variables. Yield decreased by 12.9, 15.9, 19.5, and 27.4% for T2, T3, T4, and T5, respectively, compared to T1 (p < 0.0001) across sites that were driven by similarly linear reductions in berry weight (p < 0.0001). Comparatively, berry composition varied little among treatments. Juice total soluble solids decreased linearly from T1 to T5 – though only ranged 0.9 Brix (p = 0.012). Because producers are paid by the ton, and contracts simply stipulate a target maturity level, first-year results suggest that there is no economic incentive to induce moderate water deficits before irrigation initiation, regardless of vineyard site. Subsequent years will further elucidate the carryover effects of delaying irrigation initiation on productivity over the long term.

Impact of non-fruity compounds on red wines fruity aromatic expression: the role of higher alcohols

A part, at least, of the fruity aroma of red wines is the consequence of perceptive interactions between various aromatic compounds, particularly ethyl esters and acetates, which may contribute to the perception of fruity aromas, specifically thanks to synergistic effects.1,2 The question of the indirect impact of non-fruity compounds on this particular aromatic expression has not yet been widely investigated. Among these compounds higher alcohols (HA) represent the main group, from a quantitative standpoint, of volatiles in many alcoholic beverages. Moreover, some bibliographic data suggested their contribution to the aromatic complexity by either increasing or masking flavors of wine, depending of their concentrations.

Adaptation to soil and climate through the choice of plant material

Choosing the rootstock, the scion variety and the training system best suited to the local soil and climate are the key elements for an economically sustainable production of wine. The choice of the rootstock/scion variety best adapted to the characteristics of the soil is essential but, by changing climatic conditions, ongoing climate change disrupts the fine-tuned local equilibrium. Higher temperatures induce shifts in developmental stages, with on the one hand increasing fears of spring frost damages and, on the other hand, ripening during the warmest periods in summer. Expected higher water demand and longer and more frequent drought events are also major concerns. The genetic control of the phenotypes, by genomic information but also by the epigenetic control of gene expression, offers a lot of opportunities for adapting the plant material to the future. For complex traits, genomic selection is also a promising method for predicting phenotypes. However, ecophysiological modelling is necessary to better anticipate the phenotypes in unexplored climatic conditions Genetic approaches applied on parameters of ecophysiological models rather than raw observed data are more than ever the basis for finding, or building, the ideal varieties of the future.

2018 updates on the agronomic performances of fungus resistant wine grapes in Trentino (Italy)

On the market there are several wine grapes which are tolerant to the main fungal diseases. These varieties, commonly defined “resistant”, were developed in the grapevine breeding programs carried out mainly in Germany, France, Hungary and Italy. Some of these cultivars have been included in the national catalogues of wine grape varieties and have sometimes been allowed for specific kinds of wine. The VEVIR project, aimed at the enological evaluation of resistant vines, involves 33 cultivars achieved at the State Institute for Viticulture Freiburg in Germany, the Research Institute of Viticulture and Enology Pecs in Hungary and the Fondazione Edmund Mach S. Michele all’Adige (FEM) in Italy.