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IVES 9 IVES Conference Series 9 Sustaining wine identity through intra-varietal diversification

Sustaining wine identity through intra-varietal diversification

Abstract

With contemporary climate change, cultivated Vitis vinifera L. is at risk as climate is a critical component in defining ecologically fitted plant materiel. While winegrowers can draw on the rich diversity among grapevine varieties to limit expected impacts (Morales-Castilla et al., 2020), replacing a signature variety that has created a sense of local distinctiveness may lead to several challenges. In order to sustain wine identity in uncertain climate outcomes, the study of intra-varietal diversity is important to reflect the adaptive and evolutionary potential of current cultivated varieties. The aim of this ongoing study is to understand to what extent can intra-varietal diversity be a climate change adaptation solution. With a focus on early (Sauvignon blanc, Riesling, Grolleau, Pinot noir) to moderate late (Chenin, Petit Verdot, Cabernet franc) ripening varieties, data was collected for flowering and veraison for the various studied accessions (from conservatory plots) and clones. For these phenological growing stages, heat requirements were established using nearby weather stations (adapted from the GFV model, Parker et al., 2013) and model performances were verified. Climate change projections were then integrated to predict the future behaviour of the intra-varietal diversity. Study findings highlight the strong phenotypic diversity of studied varieties and the importance of diversification to enhance climate change resilience. While model performances may require improvements, this study is the first step towards quantifying heat requirements of different clones and how they can provide adaptation solutions for winegrowers to sustain local wine identity in a global changing climate. As genetic diversity is an ongoing process through point mutations and epigenetic adaptations, perspective work is to explore clonal data from a wide variety of geographic locations.

DOI:

Publication date: May 31, 2022

Issue: Terclim 2022

Type: Article

Authors

Etienne Neethling1, Eric Duchêne2, Cornelius van Leeuwen3, Elisa Marguerit3, Etienne Goulet4 and Virginie Grondain4

1USC 1422, GRAPPE INRAE, Ecole Supérieure d’Agricultures, Angers, France
2UMR 1131 SVQV, University of Strasbourg-INRAE, Colmar, France
3EGFV, Univ. Bordeaux, Bordeaux Sciences Agro, INRAE, ISVV, Villenave d’Ornon, France
4IFV, Institut Français de la Vigne et du Vin, Beaucouzé, France

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Keywords

adaptation, climate change, clone, diversification, identity, intra-varietal, Vitis vinifera

Tags

IVES Conference Series | Terclim 2022

Citation

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