The performance of grapevines on identified terroirs in Stellenbosch, South Africa

Abstract

A terroir can be defined as a natural unit that is characterised by a specific agricultural potential, which is imparted by natural environmental features, and is reflected in the characteristics of the final product. Preliminary terroirs were defined for Stellenbosch for Sauvignon blanc and Cabernet Sauvignon using decision trees built on analyses of viticultural, oenological and environmental data measured on a network of plots over 7 seasons. This study was considered to be a preliminary approach to determine the validity of terroir studies for the South African wine industry.
It was expected that measurement of viticultural and oenological variables would serve to validate or refine the decision trees constructed with the first set of data and that the measurement of ecophysiological parameters on a separate network of reference plots would facilitate improved understanding of the grapevine x terroir interaction. Three plots of 10 vines each were therefore identified in selected commercial vineyards of Cabernet Sauvignon and Sauvignon blanc using remote sensing as a tool to identify homogenous plots where possible. These vineyards were representative of dominant terroir units that were identified for each cultivar. This network of experimental plots was monitored with respect to their ecophysiological response to the growing environment. This included dynamics of canopy development, vegetative growth, dynamics of berry growth and composition and wine character. Pre-dawn leaf water potential was determined at different stages during the growth season. The growing environment was characterised with respect to soil and climate by means of direct observations and measurements and interpolated values from the agroclimatic weather station network.
This paper will examine the results from three seasons for selected Sauvignon blanc and Cabernet Sauvignon vineyards from this network and compare these results to previous findings.

DOI:

Publication date: December 8, 2021

Issue: Terroir 2008

Type : Article

Authors

Victoria A CAREY (1), Valérie BONNARDOT (2), Zelmari COETZEE (3) & Laure DU COS DE ST BARTHELEMY (4)

(1) Lecturer and 3 Technical assistant, Department of Viticulture and Oenology, Stellenbosch University, Private Bag X1, 7602 Matieland, South Africa
(2) Agroclimatological consultant, Bureau d’Études et de Recherches en Climatologie Appliquée à la Viticulture
(4) Masters student, SupAgro Montpellier and affiliated student, Stellenbosch University

Contact the author

Keywords

Sauvignon blanc, Cabernet Sauvignon, soil, ecophysiology, Stellenbosch

Tags

IVES Conference Series | Terroir 2008

Citation

Related articles…

Anthocyanins, flavonols and hydroxycinnamates of eight vitis vinifera cultivars from the balearic islands

In 2008 the anthocyanin, flavonol and hydroxycinnamate (HCT) contents of the skins of five coloured berry cultivars (‘Escursac’, ‘Esperó de Gall’, ‘Galmeter’, ‘Valent negre’ and ‘Vinater negre’), of two white cultivars (‘Argamussa’ and ‘Prensal blanc’) and of one weakly rose cultivar (‘Giró ros’), native from Balearic Islands, were characterized.

ANALYZING THE ROLE OF ELEMENTAL SULFUR IN GRAPE JUICE ON THE DEVELOPMENT OF POLYFUNCTIONAL MERCAPTANS IN SAUVIGNON BLANC WINES

Sauvignon blanc is characterized by distinctive aromas, both fruity and herbaceous. The “green” character has been attributed to the methoxypyrazines, while the “fruity” character is associated with polyfunctional mercaptans . Polyfunctional mercaptans are of great significance due to their high impact on wines and associated low perception thresholds.
Elemental sulfur (S⁰) is widely used to protect grapevines from powdery mildew.

Extraction of stilbenes from grape cane waste and their possible applications

Vine pruning residues constitute a significant fraction of vitivinicultural waste; in fact, depending on the variety and training system, they can reach 1-5 tons/ha/year.

Defining the mechanisms and impact of winemaking treatments on tannin and polysaccharides in red wine: recent progress in creating diverse styles

Tannin and polysaccharide concentration and composition is important in defining the texture of red wines, but can vary due to factors such as cultivar, region, grape ripeness, viticultural practices and winemaking techniques. However, the concentration and composition of these macromolecules is dependent not only on grape tannin and polysaccharide concentration and composition, but also their extractability and, in the case of polysaccharides, their formation by yeast. Through studies into the influence of grape maturity, winemaking and sensory impacts of red grape polysaccharides, seed and skin tannins, recent research in our laboratory has shown that the processes involved in the extraction of these macromolecules from grapes and their retention in wine are very complex.

Sustainable management of grapevine trunk diseases

Grapevine trunk diseases (GTD) occur wherever grapes are grown and are considered the main biotic factor reducing yields and shortening vineyards’ lifespan. Currently, no product is available to eradicate GTD once grapevines are infected. Therefore, prophylactic strategies based on pruning wound protection and ‘remedial surgery’, the only eradication method based on the elimination of infected wood and renewal of the vine by means of new canes or suckers, are the only effective strategies available. The Canadian grape and wine industry focusses on a sustainable production and thus, looking for alternatives to chemicals for disease management is a top priority.