Macrowine 2021
IVES 9 IVES Conference Series 9 Macrowine 9 Macrowine 2021 9 Grapevine diversity and viticultural practices for sustainable grape growing 9 Within-vineyard spatial variation impacts methoxypyrazine accumulation in the rachis of Cabernet-Sauvignon

Within-vineyard spatial variation impacts methoxypyrazine accumulation in the rachis of Cabernet-Sauvignon

Abstract

AIM: To investigate the impact of spatial variation in vine vigour on the accumulation of methoxypyrazines in the rachis of Cabernet-Sauvignon. Cabernet-Sauvignon rachis has been shown to contain significantly higher concentrations of 3-isobutyl-2-methoxypyrazine (IBMP) than that found in berry material. IBMP is readily extracted from rachis during fermentation and can impact the flavour profile of the produced wine1.

METHODS: Cabernet-Sauvignon vines (n = 105) grown on common rootstocks in Coonawarra, South Australia, were georeferenced and 6 bunches were harvested from each vine at maturity in 2020. Berries were removed and the rachis was analysed for IBMP by GC-MS/MS. Pruning weights were recorded as an indicative measure of vegetative growth over the past season. Visualisation and analysis of map layers was achieved through linear regression models and k-means clustering with the Precision Agriculture Tools plugin2 for QGIS software suite3.

RESULTS: Georeferenced maps of vine vigour and IBMP concentration in rachis showed similar spatial variance and a clear relationship between the two variables was evident across the vineyard. k-Means clustering revealed 3 distinct zones identified as high, medium, or low in both IBMP levels and vine vigour. Although rootstock influenced vine vigour, rootstock effects were much less than the variation in vine vigour caused by inherent vineyard variability, most likely variation in soil depth4. Linear regression between vine vigour and IBMP in rachis showed a statistically significant relationship (p < 0.001) and highlighted increases in vine vigour, which increased canopy size and decreased porosity, resulted in an increase of IBMP in rachis.

CONCLUSIONS

Vine vigour significantly correlates with IBMP in Cabernet-Sauvignon rachis. Their similar patterns of within-vineyard variation provide opportunities for grape growers to implement targeted management of vineyards in a zonal fashion.

DOI:

Publication date: September 2, 2021

Issue: Macrowine 2021

Type: Article

Authors

Ross Sanders

Ross, SANDERS, Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide, and Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food,Paul, BOSS, Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food, and Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide Dimitra, CAPONE, Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide Catherine, KIDMAN, Wynns Coonawarra Estate Rob, BRAMLEY, Commonwealth Scientific and Industrial Research Organisation (CSIRO) Agriculture and Food David, JEFFERY, Australian Research Council Training Centre for Innovative Wine Production, The University of Adelaide

Contact the author

Keywords

coonawarra, georeferenced, ibmp, rootstock, vigour

Citation

Related articles…

The wine: a never-ending source of H2S and methanethiol

Volatile sulfur compounds (VSCs), mainly hydrogen sulfide and methanethiol (H2S and MeSH), are the responsible for reductive off-odor in wine.

Evaluation of phenology, agronomic and oenological quality in minority wine varieties in Madrid as a strategy for adaptation to climate change

The main phenological stages (budburst, flowering, veraison, and ripeness) and the fruit composition of 34 Spanish minority varieties were studied to determine their cultivation potential and help winegrowers adapt their production systems to climate change conditions. In total, 4 control cultivars, and 30 minority varieties from central Spain were studied during a period of 3 campaigns, in the ampelographic collection “El Encín”, in Alcalá de Henares, Madrid. Agronomic and oenological characteristics such as yield, and total soluble solids concentration have been monitored.

Carbon isotope discrimination in berry juice sugars: changes in response to soil water deficits across a range of vitis vinifera cultivars

In wine producing regions around the world, climate change has the potential to decrease the frequency and amount of precipitation and increase average and extreme temperatures. This will lower soil water availability and increase evaporative demand, thereby increasing the frequency and intensity of water deficit experienced in vineyards. Among other things, grapevines manage water deficit by regulating stomatal closure. The dynamics of this regulation, however, have not been well characterized across the range of Vitis vinifera cultivars. Providing a method to understand how different cultivars regulate their stomata, and hence water use in response to changes in soil water deficits will help growers manage vineyards and select plant material to better meet quality and yield objectives in a changing climate.

Un Système d’Informations à Références Spatiales sur le Vignoble. Un outil performant d’aide aux recherches sur la caractérisation des terroirs viticoles

The “Terroirs d’Anjou” project led by the Agronomy sector of the Vine and Wine Research Unit of the INRA center in Angers aims to characterize the viticultural terroirs in a study area which includes 29 municipalities in the Maine et Loire and cuts across the Anjou, Coteaux du layon and Coteaux de l’Aubance appellation areas.

Is wine terroir a valid concept under a changing climate?

The OIV[i] defines terroir as a concept referring to an area in which collective knowledge of the interactions between the physical and biological environment (soil, topography, climate, landscape characteristics and biodiversity features) and vitivinicultural practices develops, providing distinctive wine characteristics. Those are perceptible in the taste of wine, which drives consumer preference and, therefore, wine’s value in the marketplace. Geographical indications (GI) are recognized regulatory constructs formalizing and protecting the nexus between wine taste and the terroir generating it. Despite considering updates, GIs do not consider the nexus as a dynamic one and do not anticipate change, namely of climate. Being climate a fundamental feature of terroir, it strongly impacts wine characteristics, such as taste. According to IPCC[ii], many widespread, rapid and unprecedented changes of climate occurred, some being irreversible over hundreds to thousands of years. Climatic shifts and atmospheric-driven extreme events have been widely reported worldwide. Recent climatic trends are projected to strengthen in upcoming decades, whereas extremes are expected to increase in frequency and intensity, forcing wines away from GI definitions. Geographical shifts of viticultural suitability are projected, often moving into regions and countries different from current ones. Some authors propose adaptation in viticulture, winemaking and product innovation. We show evidence of climate changing wine characteristics in the Douro valley, home of 270-year-old Port GI. We discuss herein resist or adapt stances for when climate changes the nexus between terroir and wine characteristics. Using the MED-GOLD[iii] dashboard, a tool allowing for easy visual navigation of past and future climates, we demonstrate how policymakers can identify future moments, throughout the 21st century under different emission scenarios, when GI specifications will likely need updates (e.g., boundaries, varieties) to reduce climate-change impacts.