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…

Assessing the relationship between cordon strangulation, dieback, and fungal trunk disease symptom expression

Grapevine trunk diseases including Eutypa dieback are a major factor in the decline of vineyards and may lead to loss of productivity, reduced income, and premature reworking or replanting. Several studies have yielded results indicating that vines may be more likely to express symptoms of vascular disease if their health is already compromised by stress. In Australia and many other wine-growing regions it is a common practice for canes to be wrapped tightly around the cordon wire during the establishment of permanent cordon arms. It is likely that this practice may have a negative effect on health and longevity, as older cordons that have been trained in this manner often display signs of decay and dieback, with the wire often visibly embedded within the wood of the cordon. It is possible that adopting a training method which avoids constriction of the vasculature of the cordon may help to limit the onset of vascular disease symptom expression. A survey was conducted during the spring of two consecutive growing seasons on vineyards in South Australia displaying symptoms of Eutypa lata infection when symptomless shoots were 50–100 cm long. Vines were assessed as follows: (i) the proportion of cordon exhibiting dieback was rated using a 0–100% scale; (ii) the proportion of canopy exhibiting foliar symptoms of Eutypa dieback was rated using a 0–100% scale; (iii) the severity of strangulation was rated using a 0–4 point scale. Images were also taken of each vine for the purpose of measuring plant area index (PAI) using the VitiCanopy App. The goal of the survey was to determine if and to what extent any correlation exists between severity of strangulation and cordon dieback, in addition to Eutypa dieback foliar symptom expression.

Bioclimatic shifts and land use options for Viticulture in Portugal

Land use, plays a relevant role in the climatic system. It endows means for agriculture practices thus contributing to the food supply. Since climate and land are closely intertwined through multiple interface processes, climate change may lead to significant impacts in land use. In this study, 1-km observational gridded datasets are used to assess changes in the Köppen–Geiger and Worldwide Bioclimatic (WBCS)

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.

Current climate change in the Oplenac wine-growing district (Serbia)

Serbian autochthonous vine varieties Smederevka (for white wines) and Prokupac (for rosé and red wines) are the primary representatives of typical characteristics of wines and terroir of numerous wine-growing areas in Serbia. In the past, these varieties were the leading vine varieties, however, as the result of globalization of winemaking and the trend of consumption of wines from widely prevalent vine varieties, they were replaced by introduced international varieties. Smederevka and Prokupac vine varieties are characterized by later time of grape ripening, and relative sensitivity to low temperatures. Climate conditions can be a restrictive factor for production of high-quality grapes and wine and for the spatial spreading of these varieties in hilly continental wine-growing areas.
This paper focuses on the spatial analysis of changes of main climate parameters, in particular, analysis of viticultural bioclimatic indices that were determined for the purposes of viticulture zoning of wine-growing areas in the period 1961-2010, and those same parameters determined for the current, that is, referential climate period (1988-2017). Results of the research, that is, analysis of climate changes indicate that the majority of examined climate parameters in the Oplenac wine-growing district improved from the perspective of Smederevka and Prokupac vine varieties. These studies of climate conditions indicate that changes of analyzed climate parameters, that is, bioclimatic indices will be favorable for cultivation of varieties with later grape ripening times and those more sensitive to low temperatures, such as the autochthonous vine varieties Smederevka and Prokupac, therefore, it is recommended to producers to more actively plant vineyards with these varieties in the territory of the Oplenac wine-growing district.

Impact of yeast derivatives to increase the phenolic maturity and aroma intensity of wine

Using viticultural and enological techniques to increase aromatics in white wine is a prized yet challenging technique for commercial wine producers. Equally difficult are challenges encountered in hastening phenolic maturity and thereby increasing color intensity in red wines. The ability to alter organoleptic and visual properties of wines plays a decisive role in vintages in which grapes are not able to reach full maturity, which is seen increasingly more often as a result of climate change. A new, yeast-based product on the viticultural market may give the opportunity to increase sensory properties of finished wines. Manufacturer packaging claims these yeast derivatives intensify wine aromas of white grape varieties, as well as improve phenolic ripeness of red varieties, but the effects of this application have been little researched until now. The current study applied the yeast derivative, according to the manufacture’s instructions, to the leaves of both neutral and aromatic white wine varieties, as well as on structured red wine varieties. Chemical parameters and volatile aromatics were analyzed in grape musts and finished wines, and all wines were subjected to sensory analysis by a tasting panel. Collective results of all analyses showed that the application of the yeast derivative in the vineyard showed no effect across all varieties examined, and did not intensify white wine aromatics, nor improve phenolic ripeness and color intensity in red wine.