Aim of the study:
A study on Sauvignon blanc (SB) cultivar in France showed that curettage had an effect on the resilience of grapevine trunk diseased (GTD) grapevines. No experiments, however, have been conducted on its effects on wine quality, particularly on white SB cultivar wines. In this study, the effect of Esca on the must and wine quality of SB was investigated.
Methods and results:
Grapevines from Sauvignon blanc cultivar that had expressed Esca-foliar symptoms were used for the study, with some of them having been curetted in 2014. Subsequently, bunches from Control (asymptomatic), Curetted and Esca-symptomatic vines were harvested in 2017 and 2018 in order to produce white wine. Technical and chemical results on both must and wine showed that wines from curetted plants were similar to those from asymptomatic vines. There were differences, however, for Esca-diseased vines, where the alcoholic fermentation of musts was faster than for the other modalities. Olfactometry results showed that, for the one-year-old 2017 vintage wines, no differences were detected, although they were for the 2018 vintage.
The results of the chemical analyses and wine tasting showed that the wines from curetted and asymptomatic grapevines were similar, and that their quality was the same.
Significance of the study:
The quality of wines from curetted vines compared to asymptomatic ones was confirmed and validated through chemical and sensory analyses of the must and the one-year-old wines. Curettage could thus be a future solution to tackling Esca with the advantages of (I) avoiding having to replace Esca-diseased vines by young plants, and (II) maintaining the bunch quality of aged vines in order to preserve the typicity of Sauvignon blanc.
Reference: Bruez, Émilie, Cholet, C., Thibon, C., Redon, P., Lacampagne, S., Martignon, T., Giudici, M., Darriet, P., & Gény, L. (2021). Influence of curettage on Esca-diseased Vitis vinifera L. cv. Sauvignon blanc plants on the quality of musts and wines. OENO One, 55(1), 171–182.
Link to article: https://doi.org/10.20870/oeno-one.2021.55.1.4479
Image credit: https://www.wineland.co.za/esca-in-sa-vineyards/
This abstract is republished in its original form, with more details around the aim and significance of the project, as permitted by the following Creative Commons licence: https://creativecommons.org/licenses/by-nc-nd/4.0/