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IVES 9 IVES Conference Series 9 Evaluation of the site index model for viticultural zoning

Evaluation of the site index model for viticultural zoning

Abstract

[English version below]

Une variable composite, dénommée Indice de Site (SI), intégrant les propriétés physiques du sol et le mésoclimat, avait été proposée pour caractériser les terroirs dans le cadre d’une étude des vignobles de Cabernet Sauvignon de Hawke’s Bay en Nouvelle Zélande. L’objet du présent exposé est l’analyse de bases de données viticoles du Val de Loire (France) constituées à partir de parcelles d’essai « terroirs » de Cabernet franc et de Chenin, sur de plus longues périodes. Dans les cas où les valeurs du SI étaient faibles, aucune corrélations entre le SI et les paramètre viticole n’ont été observés. L’index de site peut être un outil additionel s’ajoutant à la liste des charactéristiques servant à évaluer les vignobles. Le SI serait particulièrement utile lorsque les variables tel que profondeur du sol, texture, présence de cailloux, de même que les conditions hydriques et température ambiante de l’air sont particulièrement différentes au niveau des sites comparés.

A composite variable termed the Site Index (SI), integrating soil physical properties and mesoclimate, was previously proposed for characterisation of vineyard sites based on a three-year study of Cabernet Sauvignon vineyards in the Hawke’s Bay region of New Zealand. In this paper, viticultural data collected from Chenin Blanc and Cabernet Franc vineyard sites in the Loire Valley (France) were analysed. These analyses provided an opportunity for validation and understanding of limitations of the SI model. The relationship between SI and Chenin Blanc fruit composition in Anjou was found to be similar to that determined in the New Zealand study. In this study, a modified SI that included winter rainfall was found to be a better predictor of grapevine vigour than original SI. In cases when the range of SI values between sites was small, no significant correlation between SI and viticultural variables was observed. Factor analysis extracted one factor best related to SI and fruit quality potential, and the second factor related to modified SI that included winter rainfall and vegetative vigour. It was determined that SI has the potential to be included as an additional indicator to the range of attributes available for vineyard site evaluation. It would be particularly useful where input variables (soil depth, texture, rockiness, water influx and air temperature) are considerably different between sites that are being compared.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

D. Tesic (1) and G. Barbeau (2)

(1) National Wine and Grape Industry Centre, Charles Sturt University, Wagga Wagga, NSW, Australia
(2) Unite de recherches sur le vigne et le vin, INRA Centre d’Angers. 42, Rue Georges Morel BP57, 49071 Beaucouze CEDEX, France

Contact the author

Keywords

Terroir, modelling, phenology, fruit composition, Chenin Blanc, Cabernet Franc

Tags

IVES Conference Series | Terroir 2004

Citation

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