Terroir 2020 banner
IVES 9 IVES Conference Series 9 The dynamics of δ13C and δ18O in musts during berries development

The dynamics of δ13C and δ18O in musts during berries development

Abstract

Aim: Many processes or reactions that occur in plants involved isotopic discrimination. Water availability, for example, affects the isotopic ratio of carbon (δ13C) and oxygen (δ18O). In viticulture, δ13C is used in experiments related to water relations and irrigation in vineyards. δ18O is used much less but it could be a good complement to δ13C. The aim of this study was to generate knowledge on how these isotopic ratios, measured in musts, could help to better understand the water behavior of grape varieties. 

Methods and Results: The present work was carried out in 2019 with a set of seven varieties selected to monitor the aforementioned ratios in musts obtained during berries development: three of them red (Bobal, Tinto Velasco and Syrah), managed with irrigation, and the other three white (Airén, Malvar and Albillo Real) kept without irrigation; the seventh, Tempranillo, was managed with or without irrigation. 

Monitoring the dynamics of isotope ratios was undertaken through sampling of grapes carried out periodically, from shortly before closing cluster to maturity. In obtained musts, δ13C and δ18O were determined by mass spectrometry of isotope ratios.

The small changes observed between samples in δ13C in a specific variety did not seem to follow any pattern. In most cases, the comparisons of means performed showed no significant differences between samples. However, differences were observed between the two management systems: irrigated and rainfed; in dry conditions, with the stomatal closure, 13C isotopic discrimination declined during photosynthesis, and the ratio then increased.

This was not so with δ18O, where the comparisons of means always showed significant differences between samples. Dynamics of δ18O seemed to adapt, in this case, to a double curve pattern (cubic polynomial): the intense increase in the ratio of the first stages of fruit development was followed by a phase of slight decline, which lasted up to 15 or 20 days before harvest, at which point the ratio increased again. There were both inter-varietal and between management system differences: musts in early harvest varieties showed higher δ18O values than late varieties, while the isotopic enrichment was lower for this isotopic ratio in irrigated vines.

Conclusions:

Differences in the narrow margin in which δ13C values of the grapes are maintained throughout their development seemed to respond more to the crop management practice than to the variety. However, the notable changes in δ18O values seem to be due to a complex mechanism that involves the discharge of water in the grapes from the phloem at beginning of ripening and the loss of water due to transpiration through the skin.

Significance and Impact of the Study: In the search for the genotypes with the highest water efficiency that effectively respond to the proliferation and dilation of drought periods that are expected in many regions, it is urgent to explore the existing genetic variability. In this sense, δ13C and δ18O could be useful tools to take into account in any research related to water use by cultivars at physiological or agronomic levels.

DOI:

Publication date: March 17, 2021

Issue: Terroir 2020

Type: Video

Authors

Adelaida Mena Morales*, Juan Luis Chacón Vozmediano, Rosa Mª Sánchez-Gil Jimeno, Jesús Martínez Gascueña

Instituto Regional de Investigación y Desarrollo Agroalimentario y Forestal de Castilla-La Mancha (IRIAF), IVICAM, Ctra. Toledo-Albacete s/n, 13700 Tomelloso, Ciudad Real, Spain

Contact the author

Keywords

Grapevine, genotypes, musts, δ13C dynamics, δ18O dynamics, IRMS

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Multidisciplinary assessment of selective harvesting in the Colli Piacentini wine district

Within-field variability can be managed through Precision Viticulture (PV) protocols aiming at identifying homogeneous zones and addressing site-specific operations including selective harvesting (SH). Several authors demonstrated SH profitability in extensive viticulture while few information is available within the Italian context.

Impact of climate change on the aroma of red wines: a focus on dried fruit aromas

The volatile composition of grapes (free and bound forms) contributes greatly to the varietal aroma and quality of wines. Several agronomical parameters affect grapes composition and wine quality: maturity level at harvest, water status, and the intensity of sun exposure.

Can the use of rootstocks enhance terroir?

Rootstocks are an essential l management tool for diverse viticultural challenges. However, studies that combine sensory evaluation and compositional analysis of berries and wine, to determine whether the use of a particular rootstock in a terroir can influence wine quality are sparse.

Smartphone as a tool for deficit irrigation management in Vitis vinifera  

Vine water status is one of the most influential factors in grape vigor, yield, and quality (Ojeda et al., 2002; Guilpart et al., 2014). Severe water deficits during the first stage of crop development (bud break to fruit set) impact yield in the current year and the following year. While during grape ripening, water availability impacts berry size, grape composition, and health status. Therefore, a correct assessment of plant water status allows for proper water management with an impact on grape yield and composition (McClymont et al, 2012; Pereyra et al., 2022).

Méthodologie pour application et valorisation des études de terroir dans les caves cooperatives des Côtes du Rhône (France)

L’appellation d’origine contrôlée “Côtes du Rhône” se caractérise par une très forte implantation du mouvement coopératif. Afin de mieux exploiter le potentiel qualitatif de leurs terroirs, plusieurs coopératives élaborent des “cuvées terroir”, résultat des sélections de vendanges provenant de différents secteurs.