The main objective of the study was to test if rootstock has any influence on Pinot noir berry and wine phenolic composition, and, if so, whether it could be related to the nitrogen (N) status of the scion.
Grapevine rootstocks can affect the N status of the grafted plant due to discrepancies in their nutrient uptake and their efficiency in the allocation of assimilates. When N becomes a limiting factor, the production of phenolic compounds in grapes is enhanced as a result of a down-regulation of the flavonoid production pathway. However, it is still not fully understood if the impact of rootstocks on fruit and wine composition is mediated by their effect on the vegetative growth and N status of the scion.
An investigation was carried out on Pinot noir vines grafted onto six rootstocks over three vintages (2012–2014). A micro-scale fermentation technique was used to produce wines from each field replicate.
Scions grafted onto SO4, a high vigour rootstock, were characterised by a 15 % higher tannin concentration in berry seed and skin compared to those grafted onto the low vigour Riparia Gloire de Montpellier, while final tannin concentration in wines depended on the rootstock. Anthocyanin concentration was higher in berries of Pinot noir grafted onto R110 compared to 125AA, which was also reflected in the wines. A Multiple Linear Regression analysis suggested that rootstock influence on berry anthocyanins was linked to the N status of scion leaves (higher Leaf NBI_R).
Significance of the study
Understanding the interaction between the N uptake efficiency of rootstocks and scion berry/wine phenolic composition will help improve the selection of suitable rootstocks that match the desired wine profile.
Reference: Blank, M., Samer, S., & Stoll, M. (2022). Grapevine rootstock genotypes influences berry and wine phenolic composition (Vitis vinifera L. cv. Pinot noir). OENO One, 56(1), 133–144. https://doi.org/10.20870/oeno-one.2022.56.1.4459
Link to article: https://oeno-one.eu/article/view/4459
This abstract is republished in its original form, with Significance paragraph and headings inserted, as permitted by the following Creative Commons licence: https://creativecommons.org/licenses/by-nc-nd/4.0/
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