Terroir 2004 banner
IVES 9 IVES Conference Series 9 Climatic zoning of viticultural production periods over the year in the tropical zone: application of the methodology of the Géoviticulture MCC system

Climatic zoning of viticultural production periods over the year in the tropical zone: application of the methodology of the Géoviticulture MCC system

Abstract

L’objectif de cette recherche est le zonage climatique des périodes viticoles de l’année dans la Vallée du São Francisco, région brésilienne productrice de vins située en climat tropical semi-aride. Dans cette région, la production peut être échelonnée sur tous les mois de l’année. La région est placée sur climat viticole à variabilité intra-annuelle, qui correspond aux régions qui, sur des conditions climatiques naturelles, changent de classe de climat viticole en fonction de la période de l’année au cours de laquelle le raisin peut être produit. La méthodologie adoptée est celle du Système de Classification Climatique Multicritères Géoviticole (Système CCM Géoviticole) (Tonietto & Carbonneau, 2004), en utilisant les fonctionnalités de modulation des indices (indices homologues appliqués sur la phénologie locale des cépages). Les indices climatiques viticoles du Système (thermique, nycthermique et hydrique) ont été adaptés aux conditions biologiques du cépage Syrah de la région, qui présente un cycle moyen débourrement-récolte (d-r) de 4 mois. L’étude utilise une base de données climatiques journalières de la période 1976-2002, avec la simulation de 36 récoltes théoriques par an (une récolte théorique a chaque décade), soit un totale de 972 sur l’ensemble de la période étudiée. Ainsi, l’Indice Héliothermique (IH12d) à été calculé sur 4 mois tout au long de l’année. L’Indice de Fraîcheur des Nuits (IF3d) a été calculé sur les 3 décades précédentes la date théorique de récolte (période de maturation). La quantité de pluie en période de maturation (P3d) a également été prise en compte en fonction des effets sur l’incidence de pourriture. Les résultats ont permis de caractériser 3 périodes climatiques viticoles distincts dans l’année : Période “a” – conditions thermiques moins chaudes pendant le cycle d-r pour l’IH12d, conditions nycthermiques (IF3d) plus fraîches et très sec (P3d) en période de maturation ; Période “b” – climat intermédiaire entre la période “a” et “c” pour l’IF3d et l’IH12d et sec à très sec pour P3d (la période “b” peut être subdivisée en 2 sous-périodes : l’une que s’initie en sortant de la période chaude et humide “c”, avec une réserve hydrique utile au niveau du sol, et évolue avec la chute des températures ; et l’autre sous-période qui débute avec l’augmentation des températures et que finie juste avant la rentrée de la période humide “c”) ; Période “c” – Le plus chaud pour l’IF3d et l’IH12d et sub-humide pour P3d. Les résultats montrent que la production de raisin de cuve pour un même cépage présente des caractéristiques potentielles distinctes en fonction des périodes de production “a”, “b” et “c”. D’une façon générale, la période “c” est la plus susceptible a une maturité du raisin incomplète en fonction du risque de pourriture (pluie et température élevée), qui peuvent amener à une récolte avant la complète maturation du raisin. Déjà les périodes “a” et “b” sont les plus aptes a une bonne maturation du raisin. La période “a” est celle qui présente le moindre risque de pluie et des températures les plus fraîches, avec la possibilité du contrôle total de la disponibilité hydrique du sol par l’irrigation. La probabilité d’occurrence des indices climatiques à été caractérisé par décade et par quartile comme information d’aide à la décision (risque ou avantages) des périodes de production. Des études complémentaires, notamment l’estimation de la réserve hydrique potentielle (Indice de Sécheresse – IS) du sol seront développées. On peut conclure que le concept de climat viticole à variabilité intra-annuelle du Système CCM Géoviticole peut être utilisé comme élément de zonage pour l’établissement, dans un même vignoble, des périodes de l’année avec un potentiel climatique supérieur de production de raisin de cuve. Ce critère climatique va être utilisé dans le zonage intégré de la région, notamment avec les facteurs édaphiques.

The objective of this research is the viticultural climatic zoning of the production periods over the year in the São Francisco Valley, a Brazilian grape-growing region located in semi-arid tropical climate. In this region, the production can be spread over all months of the year. The region is situated in climate with intra-annual variability, that corresponds to the regions which, under natural climatic conditions, change the class of viticultural climate according to the period of the year during which the grape is produced. The methodology adopted is that of the Géoviticulture Multicriteria Climatic Classification System (Géoviticulture MCC System) (Tonietto & Carbonneau, 2004), employing the modulation functions of the indices. The viticultural climatic indices of the System have been adapted to the biological conditions of the Syrah variety, which has an average cycle of 4 months from bud burst to harvest (d-r) in the region. The study is based on a daily climate database from 1976 through 2002, simulating 36 theoretic harvests per year (one theoretic harvest at every ten 10 days), amounting to a total of 972 harvests in the whole period covered by the study. In this way, the Heliothermal Index (HI12d) was calculated over 4 months throughout the year. The Cool Night Index (IF3d) was calculated over the 30 days that preceded the theoretic harvest (maturation period). The amount of rain (P3d) in the maturation period was equally been taken into account according to the potential effect of the incidence of bunch rotting. The results have allowed to distinguish 3 climatic viticultural periods during the year: Period “a” – less warm during d-r cycle (IH12d) and for night temperatures (IF3d) and very dry (P3d); Period “b” – intermediate climate between “a” and “c” period for IF3d and IH12d and dry to very dry for P3d (the period “b” can be subdivided into 2 sub-periods: one which starts with the end of the warm and sub-humid period “c”, with a useful water reserve of the soil, and evolves with the fall of the temperatures, and another which starts with the increase of the temperatures and finishes before the sub-humid period “c” returns); Period “c” – the warmest for the IH12d and IF3d, and sub-humid for P3d. The obtained results allow defining the periods “a” and “b”, even with different climatic viticultural potential, as being the most favorable for the production of grapes for wine. The probability of occurrence of the values of the climatic indices (climatic risk or advantages) was characterized at a ten-day level throughout the year. Other index to complement the study will be included, especially the potential water balance of the soil (dryness index – IS). It can be concluded that the concept of the viticultural climate with intra-annual variability of the Géovitivulture MCC System can be used as a zoning element for establishing, in the same vineyard, periods of the year with a higher climatic potential for the production of quality grapes for wine. This climatic criterion will be used in the integrated zoning of the region, especially with the edaphic factors.

DOI:

Publication date: January 12, 2022

Issue: Terroir 2004

Type: Article

Authors

J. Tonietto (1) and A.H. de C. Teixeira (2)

(1) Embrapa – Centre National de Recherche de la Vigne et du Vin – Cnpuv, Rua Livramento, 515 ; 95700-000 – Bento Gonçalves, Brésil
(2) Embrapa – Centre de Recherche du Tropique Semi-Aride – Cpatsa

Contact the author

Keywords

Tropical, intertropical, vin, raisin, qualité, climat avec variabilité intra-annuelle, zonage climatique, Système CCM Géoviticole 

Tags

IVES Conference Series | Terroir 2004

Citation

Related articles…

‘Cabernet Sauvignon’ (Vitis vinifera L.) berry skin flavonol and anthocyanin composition is affected by trellis systems and applied water amounts

Trellis systems are selected in wine grape vineyards to mainly maximize vineyard yield and maintain berry quality. This study was conducted in 2020 and 2021 to evaluate six commonly utilized trellis systems including a vertical shoot positioning (VSP), two relaxed VSPs (VSP60 and VSP80), a single high wire (SH), a high quadrilateral (HQ), and a guyot (GY), combined with three levels of irrigation regimes based on different crop evapotranspiration (ETc) replacements, including a 25% ETc, 50% ETc, and 100% ETc. The results indicated SH yielded the most fruits and accumulated the most total soluble solids (TSS) at harvest in 2020, however, it showed the lowest TSS in the second season. In 2020, SH and HQ showed higher concentrations in most of the anthocyanin derivatives compared to the VSPs. Similar comparisons were noticed in 2021 as well. SH and HQ also accumulated more flavonols in both years compared to other trellis systems. Overall, this study provides information on the efficacy of trellis systems on grapevine yield and berry flavonoid accumulation in a currently warming climate.

δ13C : A still underused indicator in precision viticulture  

The first demonstration of the interest of carbon isotope composition of sugars in grapevine, as an integrated indicator of vineyard water status, dates back to 2000 (Gaudillère et al., 1999; Van Leeuwen et al., 2001). Thanks to the isotopic discrimination of Carbon that takes place during plant photosynthesis, under hydric stress conditions, it is possible to accurately estimate the photosynthetic activity. Ever since, δ13C has been widely applied with success to zonation, terroir studies and vine physiology research, but is still not widely used by viticulturists. This is quite astonishing by considering the impact of global warming on viticulture and the need to improve water management, that would justify a widespread use of δ13C.
The lack of private laboratories proposing the analysis, the cost of the technology, as well as the long analytical delays, have been detrimental to its development. Some laboratories tried to overcome the analytical difficulties of isotopic analysis by using fourier transformed infrared spectroscopy, as a fast and cheap alternative to the official OIV method (IRMS). These claimed FTIR models have never been published or peer reviewed and cannot be considered robust. In this work, thanks to the recent acquisition of IRMS technology, new modern and robust applications of δ13C for viticulture are proposed. This includes the use of the analysis to make parcel separations at harvesting, the possibility to increase the precision of hydric stress cartography and the potential cost reduction when compared with Scholander pressure bomb analysis.

Grapevine yield-gap: identification of environmental limitations by soil and climate zoning in Languedoc-Roussillon region (south of France)

Grapevine yield has been historically overlooked, assuming a strong trade-off between grape yield and wine quality. At present, menaced by climate change, many vineyards in Southern France are far from the quality label threshold, becoming grapevine yield-gaps a major subject of concern. Although yield-gaps are well studied in arable crops, we know very little about grapevine yield-gaps. In the present study, we analysed the environmental component of grapevine yield-gaps linked to climate and soil resources in the Languedoc Roussillon. We used SAFRAN data and IGP Pays d’Oc wine yields from 2010 to 2018. We selected climate and soil indicators proving to have a significant effect on average wine yield-gaps at the municipality scale. The most significant factors of grapevine yield were the Soil Available Water Capacity; followed by the Huglin Index and the Climatic Dryness Index. The Days of Frost; the Soil pH; and the Very Hot Days were also significant. Then, we clustered geographical zones presenting similar indicators, facilitating the identification of resources yield-gaps. We discussed the number of zones with the experts of IGP Pays d’Oc label, obtaining 7 zones with similar limitations for grapevine yield. Finally, we analysed the main resources causing yield-gaps and the grapevine varieties planted on each zone. Mapping grapevine resource yield-gaps are the first stage for understanding grapevine yield-gaps at the regional scale.

Phenolic composition of Tempranillo Blanco grapes changes after foliar application of urea

Our research aimed to determine the effect and efficiency of foliar application of urea on the phenolic composition of Tempranillo Blanco grapes. The field experiment was carried out in 2019 and 2020 seasons and the plot was located in D.O.Ca Rioja (North of Spain). The vineyard was Vitis vinifera L. Tempranillo Blanco and grafted on Richter-110 rootstock. The treatments were control (C), whose plants were sprayed with water and three doses of urea: plants were sprayed with urea 3 kg N/ha (U3), 6 kg N/ha (U6) and 9 kg N/ha (U9). The applications were performed in two phenological stages, pre-veraison (Pre) and veraison (Ver). Also, each of the treatments was repeated one week later. Control and treatments were performed in triplicate and arranged in a randomised block design. Grapes were harvested at optimum ripening stage. High-performance liquid chromatography was used to analyse the phenolic composition of the grapes. Finally, the results obtained from the analytical determinations – flavonols, flavanols and non-flavonoid (hydroxybenzoic acids, hydroxycinnamic acids and stilbenes) – were studied statistically by analysis of variance. The results showed that, in 2019, U6-Pre and U9-Pre treatments increased the hydroxybenzoic acid content in grapes, and also all foliar treatments applied at Pre enhanced the stilbene concentration. Moreover, U3-Ver was the only treatment that rose flavonol and stilbene contents in the Tempranillo Blanco grapes. In 2020, all treatments applied at Pre enhanced the flavonol concentration in grapes. Furthermore, U3-Pre and U9-Pre treatments increased stilbene content in grapes. Nevertheless, the hydroxybenzoic acid content was improved by U6-Ver and U9-Ver and besides, hydroxycinnamic acid concentration in grapes was increased by all treatments applied at Ver. In conclusion, the lower and highest dose of urea (U3 and U9), applied at pre-veraison, were the best treatments to improve the Tempranillo Blanco grape phenolic composition.

Impact of changes in pruning practices on vine growth and yield

A gradual decline in vineyards has been observed over the past twenty years worldwide. This might be explained by the climate change, practices change or the increase of dieback diseases. To increase the longevity of vines, we studied the impact of different pruning strategies in four adult and four young vineyards located in France and Spain. In France, vineyards were planted with Cabernet franc on 3309C while Spanish trials were planted with Tempranillo grafted on 110R. Vegetative expression, yield, quality of berries and wood vessels conductivity were measured. The distribution of vegetative expression, yield and berry composition between primary and secondary vegetation were quantified. Finally, tomography was used to evaluate the implication of the treatments on sap flows.
First results show that i) the respectful pruning leads to an increase of 30 to 50% more secondary shoots than the aggressive pruning in France and between 15 and 20% in Spain, ii) there is no major effect on the yield over the first two years following the implementation of the new pruning practices, although the proportion of clusters from suckers is higher on the respectful pruning method. On young vines, the development of the trunk according to a respectful pruning leads to a loss of harvest 2 years after planting. This is due to the removal, on the future trunk, of the green suckers which carrying bunches. This operation carried out in spring rather than during winter pruning, would promote a better leaf / fruit balance when the plant comes into production, and could lead to better hydraulic conduction in the vessels of the trunk. Maintaining these trials for several years will provide more robust data to assess the impact of these practices on the vines over the long term.