Terroir 2020 banner
IVES 9 IVES Conference Series 9 Vertical temperature gradient in the canopy provides opportunities to adapt training system in a climate change context

Vertical temperature gradient in the canopy provides opportunities to adapt training system in a climate change context

Abstract

Aims: The aims of this study were (1) to measure the vertical temperature gradient in the vine canopy in parcels with different vineyard floor management practices and (2) to analyze the factors influencing this gradient. The objective was to investigate whether the increase of trunk height could be an adaptation strategy to reduce air temperature in the bunch zone in a context of climate change. 

Methods and Results: The experiment for measuring the vertical temperature gradient has been set up in the Bordeaux area in 2016. Three replicates of four temperature sensors were installed on vine posts inside two adjacent vineyard parcels at different heights above ground: 30 cm, 60 cm, 90 cm and 120 cm. One parcel was managed with cover crop whereas in the other the soil was tilled.

The results of this study reveal an effect of measurement height and soil management modality on bioclimatic indices. The higher temperature sums are reached close to the ground, particularly on the parcel with cover crop. Only a small effect on delaying ripeness has been shown in this study. The increase of trunk height might minimize potential damage of both frost and heat wave events. Soil tilling also allows limiting spring frost risks. 

In order to better understand the explanatory factors impacting the vertical temperature gradients, different climatic factors (average temperature, wind, precipitation, insolation fraction) and soil moisture were studied by using the data of the weather station of Saint-Emilion (Météo-France). A strong effect of soil moisture was shown on maximum temperature gradients. Projections of climate change agree on an increase in air temperature in the future. Assuming the same rainfall patterns, this increase of temperature is likely to reduce soil moisture, and increase vertical gradients in maximum temperature. Taking into account this evolution, the increase of trunk height could be a promising adaptation. 

Conclusion: 

This study investigated the vertical temperature gradient and the driving factors for this gradient. Results show that rather than delaying the maturity, the increased of trunk height could be a solution to limit the negative impacts of frost and heat waves. This study also highlighted the impact of soil management and moisture on this gradient. 

Significance and Impact of the Study: The recent evolution of climate already has an impact on vine development and grape composition and it becomes necessary to implement adaptation strategies. The training system is one of the first potential levers for adaptation, relatively easy to implement. This study provides results on the impact of an increased of trunk height and soil management on temperature in the canopy, particularly in the fruit zone, assuming temperature profiles would not change. 

DOI:

Publication date: March 17, 2021

Issue: Terroir 2020

Type: Video

Authors

Laure de Rességuier1*, Philippe Pieri1, Romain Pons1, Pierre Boudet1, Théo Petitjean1, Séverine Mary2, Cornelis van Leeuwen1

1EGFV, University of Bordeaux, Bordeaux Sciences Agro, INRAE, ISVV, F-33882 Villenave d’Ornon, France
2VITINNOV, Bordeaux Sciences Agro, ISVV, 33175 Gradignan Cedex, France

Contact the author

Keywords

Vineyard soil management, vertical temperature gradient, grapevine training system, climate change

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Replay of the Wine Vision 2040 event

A webinar organised by the UBC Wine Research Centre, on June 25th 2020. About Wine Vision 2040 Wine Vision 2040 is delivered by wine-passionate, high-profile individuals keen to share ideas and views that will spark conversations within wine communities.  No...

Under-row low competitive herbaceous cover: A sustainable alternative to herbicide in vineyards

Weeds are undesirable plants in agroecosystems as they compete with the crop for essential resources such as light, water and nutrients, compromising the final yield and its quality.

Analysis of some environmental factors and cultural practices that affect the production and quality of the Manto Negro, Callet and Prensal Blanc varieties

45 non irrigated vineyards distributed in the DO (Denomination) Pla i Llevant de Mallorca and the DO Binissalem Mallorca were used to investigate the characteristics of production and quality and their relationships certain environmental factors and cultural practices. The grape varieties investigated are autochthonous to the island of Mallorca, Manto Negro and Callet as red and Prensal Blanc as white. All plants were measured for four consecutive years in the main production and quality parameters. Among the environmental factors, the type of soil has been studied, more specifically its water retention capacity, the planting density, the age of the vineyard and the level of viral infection. The presence or absence of virus seems to have no effect on any component studied in the varieties studied. For the white variety Prensal Blanc age is negatively correlated with production and the number of bunches, nevertheless it does not cause any effect on the required quality parameters. However, for the red varieties Callet and Manto Negro, the age of the plantation is the variable that best correlates with the quality parameters, therefore the old vines should be the object of preservation by the viticulturists and winemakers in order to guarantee its contribution to the quality of the wines made with these varieties.

Phenolic, antioxidant, and sensory heterogeneity of oenological tannins: what are their possible winemaking applications?

AIM: The aim of this work was to characterize 18 oenological tannins by the polyphenolic, antioxidant, and sensory point of view.

Impact of geographical location on the phenolic profile of minority varieties grown in Spain. II: red grapevines

Because terroir and cultivar are drivers of wine quality, is essential to investigate theirs effects on polyphenolic profile before promoting the implantation of a red minority variety in a specific area. This work, included in MINORVIN project, focuses in the polyphenolic profile of 7 red grapevines minority varieties of Vitis vinifera L. (Morate, Sanguina, Santafe, Terriza Tinta Jeromo Tortozona Tinta) and Tempranillo) from six typical viticulture Spanish areas: Aragón (A1), Cataluña (A2), Castilla la Mancha (A3), Castilla –León (A4), Madrid (A5) and Navarra (A6) of 2020 season. Polyphenolic substances were extracted from grapes. 35 compounds were identified and quantified (mg subtance/kg fresh berry) by HPLC and grouped in anthocyanins (ANT) flavanols (FLAVA), flavonols (FLAVO), hydroxycinnamic (AH), benzoic (BA) acids and stilbenes (ST). Antioxidant activity (AA, mmol TE /g fresh berry) was determined by DPPH method. The results were submitted to a two-way ANOVA to investigate the influence of variety, area and their interaction for each polyphenolic family and cluster analysis was used to construct hierarchical dendrograms, searching the natural groupings among the samples. Sanguina (A3) had the most of total polyphenols while Tempranillo (A5) those of ANT. Sanguina (A2) and (A3) reached the highest values of FLAVO, FLAVA and AA. These two last samples had also the maximum of AA. The effect cultivar and area were significant for all polyphenolic families analyzed. A high variability due to variety (>50%) was observed in FLAVA and the maximum value of variability due to growing area was detected in AA (86.41%), ANT and FLAVO (51%); the interaction variety*zone was significant only for ANT, FLAVO, EST and AA. Finally, dendrograms presented five cluster: i) Sanguina (A2); ii) Sanguina (A3); iii) Tempranillo (A5); iv) Tempranillo (A3); Terriza (A3,A5), Morate (A5,A6); v) Santafé (A1,A6); Tortozona tinta (A1,A3,A6); Tinta Jeromo (A3,A4).