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A method for producing fruiting cuttings of grapevine cv. Cabernet Sauvignon is described. The main developmental features of these cuttings are presented. The clusters reach maturity after 5 months and the period of cluster development is not shortened. Before flowering, a careful control of stem and leaf growth improves the partitioning of stored carbon towards the roots and the cluster. Vegetative growth occurs mainly between fruit set and veraison. During ripening, the leaf to fruit ratio is between 20 and 30 cm2 of leaf area per gram of fruit. In the cuttings as well as in grapevines from the vineyard, free polyamine content in the leafblade does not change during development. Conjugate polyamine content does not evolve in the same way. It peaks at veraison for vineyard leaves but decreases continuously for cuttings. A proper nutrient solution provides a minerai composition in accordance with viticultural requirements. The cuttings also behave like vineyard plants in response to different levels of potassium in the nutrient solution.

Background The acid component of grape berries, originating in the metabolism of malate and tartrate, the latter being less well-known than the former, is a key factor at play in the microbiological stability of wines destined for distillation. Grape acidity is increasingly affected by climate changes. The ability to compare two vintages with contrasted climatic conditions may contribute to a global understanding of the regulation of acid metabolism and the future consequences for berry composition. Results The results of the analyses (molecular, protein, enzymatic) of tartrate biosynthesis pathways were compared with the developmental accumulation of tartrate in Ugni blanc grape berries, from floral bud to maturity. The existence of two distinct steps during this pathway was confirmed: one prior to ascorbate, with phases of VvGME, VvVTC2, VvVTC4, VvL-GalDH, VvGLDH gene expression and abundant protein, different for each vintage; the other downstream of ascorbate, leading to the synthesis of tartrate with maximum VvL-IdnDH genetic and protein expression towards the beginning of the growth process, and in correlation with enzyme activity regardless of the vintage. Conclusions Overall results suggest that the two steps of this pathway do not appear to be regulated in the same way and could both be activated very early on during berry development. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0833-1) contains supplementary material, which is available to authorized users.

Aim: To better understand the protein composition of grape skin cell walls, we have developed a method to analyse the strongly bound cell wall proteins.Methods and results: The protocol was developed with grape skins at full maturity. The critical steps of this protocol were : (i) the elimination of cellular aggregates, (ii) the elimination of soluble proteins, and (iii) the localization of the identified proteins within the cell wall. To verify whether these three conditions were met, the decrease in the quantity of cellular aggregates was followed by optical microscopy, the removal of soluble proteins was measured by chemical assay, and the presence of proteins located in cell walls was demonstrated by extensive bioinformatic analysis. The process made it possible to obtain a four-fold reduction in the amount of cellular aggregates, a reduction in the concentration of soluble proteins below the method detection limit, and a high proportion of proteins predicted to be secreted (79 %).Conclusion: The protocol described in this paper constitutes the first method to analyse proteins strongly bound to cell walls in grape skins. However, this method excludes the identification of labile proteins or proteins weakly bound to the cell wall.Significance and impact of the study: This protocol can be used for studying the role that strongly bound cell wall proteins play in development and defense processes in grape skins.

The condition known as 'millerandage' occurs when the growth of grape berries is interrupted early in their development. By harvest, berries in the same bunch will be different sizes, and some will be particularly small. Anatomical studies have revealed that interrupted growth can occur at different stages of berry development, and hormonal factors might be involved. Polyamines are one class of hormones that play an important role in plant morphogenesis, but analysis of polyamine content and composition indicated that berries of bunches with millerandage had the same polyamine composition as those at different stages of development. However, there were differences in relationships between wall-bound polyamine, especially wall-bound DAP, and arrested growth of berries. One key cytological difference was the negative PAS staining of cell walls in very small and in mid-size berries. In biochemical terms, wall-bound polyamine (and in particular wall-bound DAP content), was higher in berries from bunches with millerandage than in normal berries during their development. The present study therefore clearly demonstrates a positive correlation between wall-bound polyamine, especially wall-bound DAP, and arrested growth of berries in bunches with millerandage.

In oenology, the notion of berry phenolic maturity is related to the phenolic content of the berry, but although to their extractability capacity in wine. Nowadays, this phenomena starts to be well understood for berry fleshy parts. Nevertheless, despite the fact that seed tannins content can be ten-fold higher than the skin one, there is few works facing seed phenolic maturity. In this context, it appears clear that the perfect knowledges of the evolution of seed tannins content, biosynthesis, location and extractability all along the berry development will be helpful to control finale wine quality.Our work, which is combining chemistry, molecular, microscopy approaches bring knew knowledges in order to better characterize the seed phenolic maturity. Drawing on this expertise, we have elaborated a new indicator of seed phenolic maturity (ScanPep), useful to estimate the harvest date, but although to choose winemaking itinerary.This study brings to light that seed phenolic metabolism is conserved through vine species. Indeed, the evolution of seed content all along the berry development seems to be shared by all the studied seeds: an augmentation of seed tannins content until veraison, followed by a period of degradation/ loss of extractability until three weeks before harvest. Vintages, species or soil natures seems to not affect this profile, but can affect structural tannins characteristics such as the percentage of galloylation, the degree of polymerisation or the finale tannins content. The flavanols synthesis which is realized in plastids and cell walls leads to a progressive tissue accumulation of tannins in seed: from seed beak to seed body, and from extern to intern tissues. Finally, by an original approach of nano-vinification, we have proved that variations of seed tannins extractability cannot be explained only by variations of seed maturity, raising the importance of wine matrix content in seed tannins extractability.; La maturité phénolique de la baie tient compte de la teneur en composés phénoliques de la baie, mais également de leur potentiel d’extractibilité dont dépend leur diffusion dans le vin. Même si ce phénomène commence à être assez bien connu, et maîtrisé pour les parties charnues de la baie, très peu de travaux portent sur la maturité phénolique du pépin. Or, la teneur en tanins des pépins pouvant, dans certains cépages, représenter jusqu’à dix fois celle de la pellicule, ils constituent une part importante des tanins de la baie. Ainsi, la connaissance parfaite de la composition tannique des pépins, de leur biosynthèse, de leur localisation ainsi que la maîtrise de leur extraction durant la vinification constituent des enjeux majeurs pour maitriser la qualité du vin fini.Notre travail, combinant des approches chimiques, moléculaires, microscopiques et œnologiques, apporte de nouvelles connaissances sur les teneurs, la biosynthèse, la localisation et l’extractibilité des tanins de pépins permettant d’élaborer un outil d’évaluation de la maturité des pépins (dénommé SCANPEP) pour aider le viticulteur dans le choix de la date de vendange et le vinificateur dans ses choix d’itinéraires de vinification.Ainsi, nos travaux ont mis en évidence une conservation du métabolisme phénolique des pépins de raisin commun à tous les cépages étudiés. Les teneurs en tanins des pépins présentent un profil en cloche jusqu’à véraison, suivie d’une période de dégradation et/ou perte d’extractibilité jusqu’à environ 3 semaines avant la vendange. Le millésime, le cépage et la nature du sol ne modifient pas ce profil mais peuvent impacter soit le degré de polymérisation, soit le pourcentage de galloylation, soit les teneurs finales en proanthocyanidines. La synthèse des flavanols, réalisée au niveau des plastes et des parois cellulaires, conduit à une accumulation tissulaire progressive des tanins, partant du bec jusqu’au corps du pépin, et des tissus les plus externes vers les plus internes. Enfin, par une originale approche de nano-vinification, nos résultats ont permis de démontrer que les variations du potentiel d’extractibilité des tanins de pépins ne pouvaient s’expliquer uniquement par les variations de maturité de ce dernier, soulevant ainsi l’importance de la composition de la matrice vin dans le phénomène d’extractibilité des tanins de pépins.

Grapevine trunk diseases, including Esca, cause the death of vines. They have been on rise in France since the ban on sodium arsenite in 2001. Since then, none effective solution has been proposed to winegrowers for this crisis which cause serious economic consequences.Grapevine surgery is a curative technique against Esca. It consists in removing infected parts of the trunk. The study seeks to quantify at short and medium term effectiveness of this operation.In comparison with healthy and diseased vines, grapevine surgery stabilizes the condition of operated vines. At medium term, they regain the same behaviour as healthy vine in terms of physiology and berry quality. They are therefore resilient.For a plot under high pressure from Esca, half of the vines operated on would be resilient and only 13% of them would have died after five years.; Les maladies cryptogamiques du bois de la vigne, dont notamment l’Esca, entraînent la mort des ceps. Elles sont en recrudescence en France depuis l’interdiction de l’arsénite de sodium en 2001. Depuis, aucun moyen de lutte efficace n’a été proposé aux viticulteurs pour répondre à cette crise sanitaire entrainant de fortes conséquences économiques.Une technique curative est réapparue pour lutter contre l’Esca : le curetage. Elle consiste à enlever les parties du tronc infectées par la maladie. L’étude s’efforce donc à quantifier l’efficacité à court et moyen terme de cette opération.En comparaison avec des ceps sains et des ceps malades, le curetage se stabilise l’état des ceps opérés. À moyen terme, ils retrouvent le même comportement qu’un cep sain en terme de physiologie et de qualité de baie. Ils sont donc bien résilients.Pour une parcelle subissant de forte pression d’Esca, au bout de cinq ans, la moitié des ceps opérés seraient résilients et seulement 13% d’entre eux seraient morts.

The grape cluster formation determinism remains the one of the undefined phenomena in grapevine physiology process. The topic has been tackled in multiple ways. However, based on all the known information, we still are not allowed to get a synthetic idea of the fundamental mechanisms that produce the appearance of inflorescential primordia in year N-1 and which could govern up to 65 to 70 % of final yield in year N. Our study focuses thus on (i) the characterization of IP formation process in grapevine latent buds (Vitis vinifera L. Merlot) and the redefinition of yield constitution, (ii) understanding IP initiation and differentiation mechanisms, and (iii) evaluating the impacts of different factors (exogenous ABA, light and leaf removal) on these mechanisms.This comprehensive study, which combines multi-scale and multi-disciplinary approaches, firstly allowed us to highlight the determinism of inflorescence induction phase in yield construction by identifying three key phases in IP formation process and by incorporating a new notion which is "IP branching degree". Secondly, it proposed certain modes of regulation of IP initiation and differentiation mechanisms by identifying three types of early markers of bud fruitfulness: molecular markers (VvCLE25-1, VvTFL1a and VvMFT1), biochemical markers (CKs/IAA balance, D-glucose and starch), and environmental markers (cumulative daily sunshine and temperature).The all-inclusive results contribute to the development of an early predictive tool of "bud fruitfulness" (and thereby the probable maximum yield) to better guide and manage the grapevine training and other cultural practices.; Le déterminisme de la formation de la grappe reste parmi les phénomènes les moins bien précisés de la physiologie de la Vigne. La question a été abordée de plusieurs façons mais les éléments de réponse obtenus ne permettent pas encore de se faire une idée synthétique des mécanismes fondamentaux qui produisent l’apparition des primordia inflorescentiels (PI) en année N-1 et qui pourraient régir jusqu’à 65 à 70% du rendement final en année N. Notre étude s’est donc focalisée sur (i) la caractérisation du processus de formation des PI dans les bourgeons latents de vigne (Vitis vinifera L. Merlot) et la redéfinition de la constitution du rendement, (ii) la compréhension des mécanismes d’initiation et de différenciation des PI et (iii) l’évaluation des impacts de différents facteurs (ABA exogène, lumière et effeuillage) sur ces mécanismes.Cette étude intégrale combinant des approches multi-échelles et multi-disciplinaires a permis dans un premier temps de mettre en évidence le déterminisme de la phase d’induction inflorescentielle dans la construction du rendement en identifiant trois phases clés du processus de formation des PI et en y intégrant une nouvelle notion qu’est le « degré de ramification des PI » ; puis dans un second temps, de proposer certains modes de régulation des mécanismes d’initiation et de différenciation des PI en identifiant trois types de marqueurs précoces de la fertilité potentielle : des marqueurs moléculaires (VvCLE25-1, VvTFL1a et VvMFT1), biochimiques (équilibre CKs/AIA, D-glucose et amidon), et environnementaux (ensoleillement et température journaliers cumulés). L’ensemble des résultats pourra contribuer au développement d’un outil prédictif précoce de la « fertilité potentielle » (et donc du rendement probable maximum) afin de mieux guider et gérer la taille et les pratiques culturales.

Phenolic composition strongly determines red wine quality: color, taste, texture and most health benefits. Vineyard environmental conditions modulate endogenous hormonal balance and gene expression which control the flavonoid biosynthetic pathway leading to final grape phenolic composition. Even when the effects of plant growth regulator applications on grape endogenous hormonal balance and quality have been studied, the effect of these substances on wine composition and quality is poorly documented. The treatment of wine grapes with plant growth regulators is a potential tool in order to modify red wine phenolic composition and quality. This thesis project describes six experiments on plant growth regulator applications on developing grapes of Vitis vinifera L., cvs Cabernet Sauvignon and Carménère. Abscisic acid, Indole-3-acetic acid and 2-chloroethylphosphonic acid were applied in different phenological stages, doses and environmental conditions: Maipo and Cachapoal regions in Chile and Bordeaux region in France, commercial and experimental vineyards and plants in containers. The effect on changes in the internal hormonal content, expression of flavonoid biosynthetic and regulatory genes and grape quality, in particular grape skin phenolic composition were examined. In addition, winemaking was performed in order to assess the effect of treatments on wine chemical and phenolic composition and on wine aroma and texture attributes judged by a sensory panel.; La composition phénolique du vin rouge détermine fortement sa qualité: couleur, goût, texture et la plupart des bienfaits pour la santé. Les conditions ambiantes de la vigne modulent l'équilibre hormonal endogène et l'expression de gènes qui contrôlent la voie de synthèse des composés flavonoïdes, en déterminant la composition phénolique finale du raisin. Même s'ils ont été étudiés, les effets des applications des régulateurs de croissance végétale sur l'équilibre hormonal endogène et la qualité du raisin, les effets de ces substances sur la composition et la qualité du vin sont pauvrement documentés. Le traitement des raisins destinés à la vinification avec des régulateurs de croissance végétale est un outil potentiel pour modifier la qualité des raisins et du vin rouge. Ce projet de thèse a pour objectif d’étudier l’impact d'applications de régulateur de croissance végétale sur la composition phénolique des raisins de Vitis vinifera L. cépages Cabernet Sauvignon et Carménère. L’acide abscissique, l’acide indole-3-acétique et l'acide 2-chloroethilphosphonique ont été appliqués à divers stades phénologiques du raisin, doses et conditions environnementales: Les essais ont été menés à Maipo et Cachapoal au Chili et à Bordeaux en France, dans des vignobles commerciaux et expérimentaux ainsi que sur des plantes cultivées en pots. Il a été examiné l'effet de ces traitements sur le contenu interne d'hormones, sur l'expression de gènes structuraux et régulateurs de la synthèse de composés flavonoides et sur la qualité des raisins, en particulier la composition phénolique de sa pellicule. De plus, des vinifications ont été réalisées à partir de raisins traités pour déterminer l'effet des traitements sur la composition chimique et phénolique du vin, ainsi que sur des attributs qualitatifs tels que les arômes et la texture des vins, jugés par un panel d'évaluation sensorielle.