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The Environs de l’étang de Longpendu map by Jean Vandamme shows a part of the Burgundy territory, located in the center of Charolais, probably at the end of the sixteenth century. It is representative of a complex corpus and shows, in various ways, a part of the Burgundy vineyards in the North, and Charolais forests and plains in the South. The vineyards shown are partly those occupied by today’s Côte de Beaune, Côte chalonnaise, Mâconnais and Couchois. This is one of the oldest representations of the vineyard in Burgundy, and a precious tool for documenting the dynamics of vineyard expansion from the 16th to the 21st century., La carte des Environs de l’étang de Longpendu de Jean Vandamme représente une partie du territoire de la Bourgogne, située au centre du Charolais, probablement à la fin du xvie siècle. Elle est représentative d'un corpus complexe et figure, de plusieurs manières, une partie des vignobles de Bourgogne au Nord et des forêts et plaines du Charolais au Sud. Les vignobles figurés sont pour partie ceux qui sont occupés par la Côte de Beaune, la Côte chalonnaise, le Mâconnais et le Couchois actuels. C'est une des plus anciennes représentations du vignoble en Bourgogne, et un outil précieux pour documenter la dynamique d'extension du vignoble du xvie au xxie siècle.

International audience; The present study is aimed at determining whether leaf volatile organic compounds (VOCs) are good markers of the grapevine response to defence elicitors in the field. It was carried out in two distinct French vineyards (Burgundy and Bordeaux) over 3 years. The commercial elicitor Bastid® (Syngenta, Saint-Sauveur, France) (COS-OGA) was first used to optimise the VOCs’ capture in the field; by bagging stems together with a stir bar sorptive extraction (SBSE) sensor. Three elicitors (Bastid®, copper sulphate and methyl jasmonate) were assessed at three phenological stages of the grapevines by monitoring stilbene phytoalexins and VOCs. Stilbene production was low and variable between treatments and phenological stages. VOCs—particularly terpenes—were induced by all elicitors. However, the response profiles depended on the type of elicitor, the phenological stage and the vineyard, and no sole common VOC was found. The levels of VOC emissions discriminated between weak (Bastid® and copper sulphate) and strong (methyl jasmonate) inducers. Ocimene isomers were constitutively present in the overall blends of the vineyards and increased by the elicitors’ treatments, whilst other VOCs were newly released throughout the growing seasons. Nonetheless, the plant development and climate factors undoubtedly influenced the release and profiles of the leaf VOCs.

International audience; Grapevine phenology and total soluble solids (TSS) accumulation are important information to plan agricultural operation in the vineyards over the season. The study aims at identifying the main environmental factors and related high spatial auxiliary information that could be used to define within-field zones of phenology and TSS accumulation. An experiment was carried out in the Maule Valley, Chile, considering two representative vineyards with different environmental characteristics: vineyard 1 (cv. Cabernet Sauvignon) which presents differences in elevation and vineyard 2 (cv. Chardonnay) which is considered flat. Within each vineyard, a regular sampling grid was defined to perform measurements: phenology, TSS accumulation, plant water status, vegetative expression, yield, soil physical properties and soil apparent electrical conductivity. Observations were made during four and two years respectively for vineyard 1 and 2. The analysis of the results is based on principal component analysis (PCA) to identify the relationships between variables. Results show that factors affecting the spatial variability of phenology and TSS accumulation are different for each vineyard. For vineyard 1, topography is the main factor that affects the spatial variability both in phenology and TSS accumulation. For vineyard 2, the soil apparent electrical conductivity was the most important factor explaining the spatial variability observed in the phenology, while balance between vegetative expression and fruit load affected the TSS accumulation. These results highlight the possibility to define zones of differentiated management in relation to the phenology and TSS accumulation using auxiliary information easy to acquire or available with high spatial resolution.

International audience; Grapevine decline is a top concern in viticulture worldwide and is often associated with many biotic and abiotic factors. Grape trunk diseases and viruses are some of the most frequently identified causes of vine dieback. However, a decline is sometimes observed when no mineral deficiency or excess, or pathogenic causes can be identified. Soil enzymatic and microbial activities are relevant bio-indicators since they are known to influence vine health. Grapevine associated microbiota, linked to vine fitness, is known to be influenced by soil microbiota coming from the microbial pool inhabiting the vineyard. This work describes the microbial diversity and activity of four different vineyard plots of the Bordeaux region, selected due to the presence of localised declining areas unexplained yet by disease symptoms. Soils were sampled in declining areas and areas within the same plot showing no decline symptoms, during autumn and spring periods. Significant differences in enzymatic activities, microbial biomass and activity were found among soils even if those soils presented quite similar physicochemical characteristics that could not explain these observed declines. The results of enzymatic assays distinguished patterns in autumn and spring periods with an overall greater enzymatic activity in soils from non-declining areas. This work suggests that soils displaying decline symptoms present a dysbiosis in functionality and diversity which is linked to vine health.

Most of my work has been concerned with the knowledge of the viticultural technical management route and the evaluation of its multiple performances. In a general way, this knowledge has the ambition to contribute to allow the viticulture to make its agroecological transition while maintaining the quality of its grapes and wines, for many Protected Designation of Origin (PDO) in France. To answer to this double constraint, I hypothesized that the vineyard technical management route and the practices that are articulated within it, are central to advance the sustainability of the vineyard systems while perpetuating the quality of grapes and wines.The major contribution of my work lies first in the knowledge and the place of technical management routes. I have described precisely the technical management routes of the vineyard and the practices that constitute it and are articulated in it. To do this, I was interested in the most common vineyard systems in France, but I also tracked down innovative vineyard systems with very low input use that could meet the challenges of the agro-ecological transition in viticulture. This allowed me to co-design with winegrowers and extension agents, vineyard systems that are much more environmentally friendly while maintaining their yield and quality performances. This knowledge also allowed me to characterize the place of the technical management route within the concepts of vineyard terroir and wine typicity, which until then had been regularly focused on the triptych soil, subsoil and climate.The major contribution of my work on the evaluation of vineyard systems is the design and adaptation of methods for evaluating sustainability (environmental, social and economic) and grape and wine quality for viticulture at different scales and with different prerequisites: (i) by enriching the environmental assessment of the specificities of the vine, a perennial crop, in relation to the maintenance of the quality of grape and wine that allow the elaboration of PDO wines; (ii) by producing environmental impact indicators at different spatial scales (plot, farm and watershed); (iii) building a socio-economic evaluation indicator for innovative low-input viticultural systems; (iv) contributing to the aggregation of environmental and quality evaluations; (v) contributing to the adaptation of LCA to viticulture.The tools that I have contributed to develop are usable beyond viticulture and existing production systems. This allows me to build a follow-up to my work.And so, at the end of this thesis, I present the research questions that I wish to address in the continuation of my research work: (i) what are the specificities of innovative viticulture and agricultural systems with very low exogen inputs? and (ii) how to evaluate the sustainability and performance of innovative viticulture and agricultural systems with very low exogen inputs?; La majeure partie de mes travaux ont concerné la connaissance de l’itinéraire technique viticole et l’évaluation de ses multiples performances. D’une façon générale, ils ont pour ambition de contribuer à permettre à la viticulture de faire sa transition agroécologique tout en maintenant la qualité de ses produits, pour beaucoup d’Appellations d’Origine Contrôlée (AOC) en France. Pour répondre à cette double contrainte, j’ai posé l’hypothèse que l’itinéraire technique viti-vinicole et les pratiques qui s’articulent en son sein, sont centraux pour faire progresser la durabilité des systèmes et tout en pérennisant la qualité des produits qui en sont issus.L’apport majeur de mes travaux réside en premier lieu dans la connaissance et la place des itinéraires techniques viticoles. J’ai décrit précisément l’itinéraire technique viticole et les pratiques qui le constituent et s’y articulent. Ces connaissances m’ont permis de caractériser la place de l’itinéraire technique au sein des concepts du terroir viticole et de la typicité des vins, qui jusque-là étaient souvent centrés sur le triptyque sol, sous-sol et climat. Je me suis intéressée aux systèmes viticoles les plus représentés sur le territoire français, et j’ai traqué les systèmes innovants par leur faible usage d’intrants et qui pourraient répondre aux enjeux de la transition agroécologique de la viticulture. En parallèle, j’ai mené des travaux de co-conception avec des viticulteurs et des agents du développement, des systèmes viticoles beaucoup plus respectueux de l’environnement tout en maintenant leurs performances agronomiques. L’apport majeur de mes travaux sur l’évaluation des systèmes viticoles est la construction et l’adaptation de méthodes d’évaluation de la durabilité (environnemental, social et économique) et de la qualité des produits pour la viticulture à différentes échelles et avec différents prérequis : (i) en enrichissant l’évaluation environnementale des spécificités de la vigne, culture pérenne, en lien avec le maintien de la qualité des produits qui permettent d’élaborer des vins d’Appellation d’Origine ; (ii) en produisant des indicateurs d’impact environnementaux à différentes échelles spatiales (parcelle, exploitation et bassin versant) ; (iii) en construisant un indicateur d’évaluation socio-économique des systèmes innovants viticoles à très bas intrants ; (iv) en contribuant à l’adaptation de l’ACV à la viticulture ; (v) en contribuant à l’agrégation des évaluations de l’environnement et de la qualité.L’application de mes outils à des systèmes viticoles innovants a rencontré certaines limites, ce qui ouvre une perspective à mes travaux.Ainsi à la fin de ce mémoire, je présente les questions de recherche que je souhaite traiter lors de la suite de mes travaux : (i) quelles sont les spécificités des systèmes agricoles innovants à très bas intrants exogènes (agroécologiques) ? et (ii) comment évaluer la durabilité et les performances des systèmes agroécologiques ?

International audience; Four clades of Plasmopara viticola isolated from wild and cultivated Vitis species were described in 2013. Only P. viticola clades riparia and aestivalis have been detected in eastern Canada. To increase our understanding of the epidemiology of these clades of P. viticola, airborne sporangia were monitored with spore samplers at two experimental vineyards from 2015 to 2018 and at 11, 14, and 15 commercial vineyards in 2016, 2017, and 2018, respectively. At each vineyard and in each year, airborne sporangia were assessed three times weekly from grapevine budbreak to harvest. To accurately monitor airborne inoculum, a specific and sensitive quantitative PCR assay for simultaneous quantification of P. viticola clades riparia and aestivalis was developed. At the experimental site, in the vineyard planted with the hybrid grape variety Chancellor, mostly P. viticola clade riparia was detected. In vineyards planted with multiple grape varieties, airborne sporangia of P. viticola clade riparia were prevalent at the beginning of the season, whereas P. viticola clade aestivalis was mostly detected from midseason to harvest. At the commercial sites, airborne sporangia of P. viticola clade riparia were more prevalent in 2016, whereas P. viticola clade aestivalis was more prevalent in 2017 and 2018. The only significant difference between the inoculum progress curves was the time at which 50% of the seasonal inoculum was reached, with an average for the 3 years of 100.8 and 117.9 days since 1 May for P. viticola clade riparia and clade aestivalis, respectively. When airborne sporangium concentrations were expressed as the proportion of the two clades, in general, the proportion of clade aestivalis to that of clade riparia was low at the beginning of the season and increased to reach approximately 0.9 to 1.0 at the end of the season. These results suggest that both clades of P. viticola coexist, but that clade aestivalis is predominant and that downy mildew epidemics caused by P. viticola clade riparia occur 2 to 3 weeks before those caused by clade aestivalis.

Hypospadias (H) is a common birth defect affecting the male urinary tract. It has been suggested that exposure to endocrine disrupting chemicals might increase the risk of H by altering urethral development. However, whether H risk is increased in places heavily exposed to agricultural pesticides, such as vineyards, remains debated and difficult to ascertain. The objective of the work is to test the possible association of H with residential proximity to vineyards. Residential address at birth of 8,766 H cases born 1980–2011 was taken from 17 specialized surgery centers. The geographical distribution of vineyards was obtained from the European Land Parcel Identification System (LPIS) and the distance of address to the nearest vineyard was computed. A first estimate of the variation of H relative risk with distance to vineyards was obtained using as controls 13,105 cryptorchidism (C) cases operated during the same period in the same centers. A separate estimate was obtained from a case-control study using “virtual controls” (VC) defined as points of the map sampled to match the demographic distribution of births within the recruitment territories of the study centers. Non-exposed patients were defined as those with a residence between 5,000 and 10,000 m from the closest vineyard. The residential distance to vineyard was smaller for H than for C cases (p−4). We found 42/8766 H cases (0.48%) and 50/13,105 C cases (0.38%) born to mothers living within 20 m of a vineyard. The odds ratios for H were 2.48 (CI: 1.0 to 5.1) and 2.4 (CI: 1.3 to 4.4), vs C or vs VC, respectively, when pregnant mothers lived 10–20 m from a vineyard. In conclusion, our study supports that children born to mothers living close to a vineyard have a two-fold increased risk of H. For environmental research, the use of VC provides an alternative to classical case control technique.

International audience; Faced with current health and environmental challenges, viticulture is directly concerned with the need to reduce pesticide use. Natural pest control services provided by bats have been demonstrated in other crops and is regularly mentioned as a way to reduce pesticide use. However, the trophic link between bats and grape pests as well as the effect of pest presence on bat activities remain largely unknown. To investigate the functional role of bats in vineyard landscapes, we used two independent approaches. We monitored the activities of bats and of the European grapevine moth (Lobesia botrana) in 23 vineyards located in the Bordeaux region (France). In parallel, we developed DNA primers to examine bat faeces from two regions, Bordeaux and Burgundy, for the presence of the three main species of grapevine moths. Our results demonstrate that bats significantly increase their hunting activity when European grapevine moths are present in vineyards. In addition, our molecular analysis of the faeces provides robust evidence that at least 10 species of bats predate the three grapevine moth species. Our results therefore suggest that bats can be natural enemies of grape pests in vineyard landscapes. Further research is now needed to investigate the consequences of predation of pests by bats on crop production as well as the effect of some management options at both the local and landscape scale to increase the level of pest control services provided by bats.

Erosion susceptibility in vineyards is approximately one order of magnitude above the reference level calculated for all agricultural activities, and preventing soil erosion is thus one of the most important environmental issues in vineyards. Spatially explicit models are necessary to address the coevolution of erosion susceptibility and anthropogenic practices because of the heterogeneous spatial patterns of erosion within vineyards. In this paper, we apply the RUSLE model to assess erosion susceptibility through time in a Burgundy vineyard (Mercurey) at a catchment scale (15 km²). The model is first calibrated with data acquired in 2015-2018. Second, erosion susceptibility during former stages (1953 and 1984) is compared to current reference frame. Such theoretical comparison considers that both C (land cover) and LS (Length-Slope) factors evolved through time. We hypothesize that such factors reveal both the land use evolution (especially agricultural land uses) and the development of a soil erosion management strategy based on the collection of sediments using roads, hedges and ditches. The current reference frame of erosion susceptibility calculated at catchment scale is about 9,152 t.yr-1. In the early 1980s a peak in erosion susceptibility is concomitant with vineyard expansion during the second half of the 20th century. Erosion susceptibility in vine parcels in 1984 is estimated to be 32% higher than current period. In the mid-20th century the spatial patterns of agricultural land use (patchwork of grasslands and vines, vines on moderately-rugged hillslopes) led to moderate rates of erosion susceptibility. At this stage, past level of erosion susceptibility is estimated to be 40% lower than current reference frame.

Agricultural workers often produce considerable excess heat due to the physically demanding nature of their activities, increasing their risk of thermal stress in even moderately warm conditions. Few studies have examined the physiological responses to heat load in agriculture. We aimed to assess the heat strain experienced by vineyard workers during canopy management in dry field conditions, and to disentangle the effects of the heat produced by the body and the thermal environment. Thirty workers from five Bordeaux vineyards of southern France were monitored during vine-lifting and trellising (June 2012). The mean heart rate, net cardiac cost, relative cardiac cost, and cardiac workload score were assessed during field activity. As the workers were nested within vineyards, multilevel linear regression models were used for correct inference. Skin temperature increased by an average of 1.0°C. Cardiac indices showed marked differences between individuals. The workload was evaluated as ‘heavy’ or ‘very heavy’ for more than one-third of the workers, of whom one experienced heat exhaustion. Above some individual characteristics, we highlighted a contextual effect (air temperature) for the mean heart rate (P = 0.03), the relative cardiac cost (P = 0.01) and, to a lesser extent, a cardiac workload score (P = 0.07). Canopy management by hand in vineyards causes considerable cardiac and thermoregulatory strain. Appropriate instruments should be developed to simultaneously evaluate work intensity, work quality, and productivity at the vineyard level to raise the awareness of both managers and employees about taking preventive measures.

While the trend in winemaking is toward reducing the inputs and especially sulphites utilization, emerging technologies for the preservation of wine is a relevant topic for the industry. Amongst yeast spoilage in wine, Brettanomyces bruxellensis is undoubtedly the most feared. In this study, UV-C treatment is investigated. This non-thermal technique is widely used for food preservation. A first approach was conducted using a drop-platted system to compare the sensitivity of various strains to UV-C surface treatment. 147 strains distributed amongst fourteen yeast species related to wine environment were assessed for six UV-C doses. An important variability in UV-C response was observed at the interspecific level. Interestingly, cellar resident species, which are mainly associated with wine spoilage, shows higher sensitivity to UV-C than vineyard-resident species. A focus on B. bruxellensis species with 104 screened strains highlighted an important effect of the UV-C, with intra-specific variation. This intra-specific variation was confirmed on 6 strains in liquid red wine by using a home-made pilot. 6624 J.L−1 was enough for a reduction of 5 log10 of magnitude for 5 upon 6 strains. These results highlight the potential of UV-C utilization against wine yeast spoiler at cellar scale.

International audience; Accumulation of copper (Cu) in soils due to the application of fungicides may be toxic for organisms and hence affect winegrowing sustainability. Soil parameters such as pH and dissolved organic matter (DOM) are known to affect the availability of Cu. In this study, we investigated the contribution of chromophoric and fluorescent DOM properties to the prediction of Cu availability in 18 organic vineyard soils in the Bordeaux winegrowing area (France). The DOM parameters, assessed through absorbance and fluorescence analyses, and proxies for Cu availability (total soluble Cu and free ionic Cu2+) were measured in 0.01 M KCl extracts. Total soluble Cu (CuKCl) varied 23-fold while free ionic Cu2+ varied by a factor of 4600 among the soils. DOC concentrations were similar among the soils, but the samples differed in the quality of DOM as assessed by optical spectroscopy. Multilinear regression models with and without DOM quality parameters were investigated to predict Cu availability. The best model for CuKCl successfully explained 83% of variance and included pH, CuT, and two DOM fluorescence quality indices, the FI fluorescence index, which distinguishes between microbial and higher plant origins, and the HIX humification index. For the prediction of Cu2+, pH alone explained 88% of variance and adding DOM parameters did not improve modelling. The two Cu availability proxies were related to pH. This study confirms the prominent role of pH in Cu availability and underlines the importance of DOM quality to better predict Cu solubility.

International audience; Fungal species involved in Esca cause the formation of grapevine wood necroses. It results in the deterioration of vascular network transport capacity and the disturbance of the physiological processes, leading to gradual or sudden grapevine death. Herein, for two consecutive growing seasons, a detailed analysis of the structural (wood necrosis and leaf discoloration) and physiological parameters related to the water use of healthy and esca-symptomatic grapevines was conducted. Measurements were carried out on 17-year-old grapevines that expressed, or not, Esca-leaf symptoms in a vineyard of the Bordeaux region (France). Whole-plant transpiration was recorded continuously from pre-veraison to harvest, using noninvasive sap flow sensors. Whole-plant transpiration was systematically about 40–50% lower in Esca-diseased grapevines compared with controls, and this difference can be observed around 2 weeks before the first Esca-foliar symptoms appeared in the vineyard. Unlike grapevine sap flow disruption, structural (e.g., leaf discolorations), functional (e.g., stomatal conductance, photosynthetic activity, phenolic compounds), and genetic (e.g., expression of leaf-targeted genes) plant responses were only significantly impacted by Esca at the onset and during leaf symptoms development. We conclude that sap flow dynamic, which was related to a high level of a white-rot necrosis, provides a useful tool to predict plant disorders due to Esca-grapevine disease.

National audience

Vines are an agricultural environment whose production management is evolving in the same way as others (conventional agriculture). Agricultural practices and land management methods have significantly disturbed ecosystems, irreparably endangering biodiversity. The extinction of species, including in the environments associated with the Jura winegrowing area, is a known fact and is still ongoing. According to Rossi, in 1996 "modernity and progress, which offer man ever more powerful means of action on nature, are essentially negative and harmful to it". This project focuses on analyzing the ecological continuities of the environments associated with the Jura vineyards in order to enable naturalist associations such as the League for the Protection of Birds (LPO) to support volunteer winegrowers in the development and management of their plots.This study uses a specific methodology to model the ecological continuities of the environments associated with the Jura vineyards using virtual species for habitats of major ecological interest. Through the method established by Epage HDHL (2020), the biodiversity hotspots are also defined for the overall study area. These models allow the identification of ecological networks through the prioritization of corridors and habitat patches for the different environments studied. These results then serve as a decision-making tool for the LPO BFC; Les vignes sont des milieux agricoles dont la gestion évolue au même titre que les autres (agriculture conventionnelle). Les pratiques agricoles et les modes de gestion de l’espace ont grandement perturbé les écosystèmes, en constituant irrémédiablement une menace pour la biodiversité. La disparition d’espèces, y compris dans les milieux associés au vignoble jurassien est avérée et encore actuelle. Selon Rossi, déjà en 1996 « la modernité et le progrès qui offrent à l’homme des moyens d’action toujours plus puissants sur la nature sont essentiellement négatifs et nocifs pour celle-ci ». Ce projet porte sur l’analyse des continuités écologiques des milieux associés au vignoble jurassien afin de permettre à des associations naturalistes telles que la Ligue pour la Protection des Oiseaux (LPO) d’accompagner les viticulteurs et viticultrices volontaires dans l’aménagement et la gestion de leurs parcelles.Cette étude met en place une méthodologie spécifique permettant de modéliser les continuités écologiques des milieux associés au vignoble jurassien à l’aide d’espèces fictives pour des habitats présentant un intérêt écologique majeur. Grâce à la méthode établie par l’Epage HDHL (2020), les réservoirs de biodiversité sont également définis sur l’ensemble de la zone d’étude. Ces modélisations permettent d’identifier les réseaux écologiques à travers la hiérarchisation des corridors et des taches d’habitat pour les différents milieux étudiés. Ces résultats servent ensuite d’outil d’aide à la décision pour la LPO BFC.

International audience; Vineyard landscapes are now recognized as a strong heritage value. They are one of the elements that contributed to the inclusion of the Loire Valley on the Unesco World Heritage list. These landscapes have been built over time by adapting to different constraints, and in particular to diseases. Indeed, vines are particularly susceptible to diseases, as the phylloxera which had disastrous consequences. Phytosanitary products were imposed after the Second World War, appearing to the winegrower as an efficient way to protect his crops and his harvests, a miracle solution. The quantities used are all the more important as the treatments are not only curative but also preventive. However, limits have appeared and it is now admitted that the systematic use of phytosanitary products has harmful effects on the environment as well as on health. Winegrowers are aware of this and, must reinvent their profession, finding new ways to fight against these multiple diseases that can compromise their crops and threaten their business. The sustainability of the emblematic landscapes born from the culture of the vine depends on it. One of the solutions being considered nowadays is Precision Vine-growing. The Vinodrone research project ("Viticulture de précision par analyse d'images et de données provenant de drones", funded by the Centre-Val de Loire region, 2017-2020) aims at investigating this avenue, focusing on early detection of diseases based on hyperspectral imagery from drones. In the framework of this project, we conducted 44 interviews, in a directed manner, with inhabitants of three wine-producing cities situated in the Loire Valley (Noyers-sur-Cher, Chinon and Amboise) or their surroundings. We will use these interviews to question the future of Precision Vine-growing: how is the use of pesticides considered in territories where vines have been part of the landscape for a long time? Are wine growers perceived as polluters and poisoners? Above all, from the point of view of the people living near their plots, should they consider turning to new technologies, in this case drones, to reduce the use of phytosanitary products? After a presentation of the significance of vine-growing landscapes in the Loire Valley, the related issues and the methodology adopted, we will analyze the consequences the use of pesticides, the feelings they arouse, and the access to information, compared with the threats identified for the vineyards. We will then see that the condemnation of phytosanitary products is not so clear-cut, mainly because the respondents are aware that diseases threaten the vineyard; they nevertheless admit to being afraid of these products, the risks of which they claim to know. We will then focus on the use of drones in the context of Precision Vine-growing, in order to question their benefits and drawbacks, especially from a societal point of view: although this technology is perceived positively, a few reservations have been expressed (cost, nuisance and the need for regulations...). Therefore, these latter must be considered in order to imagine tomorrow's vine-growing and the associated landscapes.

Arbuscular mycorrhizal fungi form a mutualistic symbiotic association with more than 80% ofland plants, including vines. Advantages of this mutualistic symbiosis are countless. Rootcolonisation by mycorrhizal fungi is mainly evaluated through staining and microscopicobservation. However those technics do not allow to differentiate different mycorrhizal fungi.In order to overcome those limits other tools, like antibodies, isoenzymes and molecular biologytechnics, can be used. Nevertheless, all of these methods “only” allow detection of the presenceof mycorrhizal fungi, whereas no information is provided on the proper mycorrhizal symbiosisfunctioning, and therefore on the benefits provided to the cultivated plants. The thesis projectaims to develop tools (diagnostic kits) for monitoring the functioning of the arbuscularmycorrhizal symbiosis, intended for professionals in the plant production sector. Thismonitoring will, among other things, validate the most favourable crop routes toward theoptimal functioning of arbuscular mycorrhizal symbiosis and therefore the ecosystem servicesprovided by this mutualistic association. These tools will be extremely useful for professionalsinvolved in the development and implementation of environmentally sound agriculturalsystems production.

International audience; Conserving functionally diverse bird communities in European farmland is becoming critical, with no exception for regions of wine production. Management intensification combined with the loss of semi-natural habitats in wine-growing landscapes has led to a long-term decline not only in birds of conservation concern but also in once common insectivores and seed eaters. These declines are expected not only to threaten key ecological services provided by vineyard birds, such as pest or weed control, but also their cultural significance. We analysed how organic management and landscape heterogeneity affected taxonomic and functional diversity of 334 bird communities from 12 regions of the three main wine-producing European countries (France, Italy and Spain). We further modelled the responses of community-level metrics measuring mean habitat specialization and bird song attractiveness to humans, as well as cumulative abundances of functional insectivores, seed and grape eaters to account for individual avian functions. We found that organic viticulture enhanced bird functional diversity and individual functions, but that its positive effect partially depended on grass cover management in the inter-rows and landscape heterogeneity. Woodland cover and landscape compositional heterogeneity increased both taxonomic and functional diversity of bird communities, as well as functional insectivory. Landscape configurational heterogeneity also increased functional diversity and mean song attractiveness of bird communities. Overall, both bird diversity and functions were enhanced by higher landscape heterogeneity, especially in organic vineyards. However, mean habitat specialization decreased with woodland cover and configurational heterogeneity, meaning that open habitat specialists preferred more even landscapes with high vineyard cover. Synthesis and applications. Our study highlights the benefits of combining organic management and partial grass cover at the field level and promoting interfaces between vineyards and semi-natural habitats at the landscape level to sustain multifunctional bird communities in wine-producing European countries.

International audience; Since its identification in 2003, little has been revealed about the spread of grapevine Pinot gris virus (GPGV), an emerging grapevine virus. According to studies from Italy, GPGV transmission in the vineyard can be fast but progressive over the years. To gain new insights into the spread of GPGV infections, we tested 67 grapevines in a single vineyard parcel in southern France. These vines were sampled over 8 years (2013 to 2020) and tested for GPGV by reverse-transcription PCR using a new primer pair designed from the recently described genetic diversity of GPGV worldwide. While focusing on a portion of the samples (n = 20), we observed a drastic increase in newly GPGV-infected vines from 2014 (5%, 1 of 20) to 2015 (80%, 16 of 20) and 2016 (90%, 18 of 20). Infected vines were scattered throughout the vineyard with no distinct pattern of distribution, and some rare vines remained negative through 2020. Using all available genomic information, we performed Bayesian-based phylogeographic analyses that identified a major intravineyard transmission in 2014 to 2015. To test our model, we analyzed 47 additional grapevines and confirmed the outbreak of GPGV in 2015, validating our in silico projection. Interestingly, some grapevines remained negative throughout the study, in spite of their close proximity to infected plants. These results raise questions about the dynamics of vector populations and environmental conditions that may be required for virus spread to occur in the vineyard.

International audience; Copper (Cu) contamination of soils may alter the functioning and sustainability of vineyard ecosystems. Cultivating Cu-extracting plants in vineyard inter-rows, or phytoextraction, is one possible way currently under consideration in agroecology to reduce Cu contamination of vineyard topsoils. This option is rarely used, mainly because Cu phytoextraction yields are too low to significantly reduce contamination due to the relatively "low" phytoavailability of Cu in the soil (compared to other trace metals) and its preferential accumulation in the roots of most extracting plants. This article describes the main practices and associated constraints that could theoretically be used to maximize Cu phytoextraction at field scale, including the use of Cu-accumulating plants grown (i) with acidifying plants (e.g., leguminous plants), and/or (ii) in the presence of acidifying fertilizers (ammonium, elemental sulfur), or (iii) with soluble "biochelators" added to the soil such as natural humic substances or metabolites produced by rhizospheric bacteria such as siderophores, in the inter-rows. This discussion article also provides an overview of the possible ways to exploit Cu-enriched biomass, notably through ecocatalysis or biofortification of animal feed.

In viticulture, as in many fields, the adoption of modern methods is an essential step in order to guarantee compliance with quality standards. Remote sensing, making it possible to map, analyze and treat vineyards is today a modern solution for efficiently managing vineyard plots. In addition, the use of multispectral sensors, in particular infrared and near infrared, provides key indicators that could helpto diagnose a plot, in particular by generating a normalized difference vegetation index (NDVI) map.Finally, 3D reconstruction methods offer a real contribution to the vineyard diagnosis, since they allow precise measurements that could be made directly from the 3D model.While several solutions exploit the different strengths of these methods, they simply treat these indicators separately. Thus, it is possible to obtain a 3D map from specific sensors, a 2D NDVI map can be generated using infrared images and aerial images are regularly taken from a drone or satellite to analyze the evolution of a vineyard.The objective of this thesis is to show that it is possible to combine these indicators in order to provide a 3D NDVI map of a plot from aerial images taken by a drone with a spécific pair of sensors embedded.We propose in the first part of this manuscript the context in which our study is placed. We introduce the notion of 'precision viticulture', and establish a state of the art of the various remote sensing methods applied to the study of the health state of the vine.In a second part, we focus in 3D reconstruction by stereo vision, and propose several methods to improve the quality of the point cloud generated.We will investigate in a third part the 3D reconstruction methods from a system involving only one camera. In this part, we present a method for optimizing the number of images processed in order to lighten the solutions on embedded systems; as well as a convolutional neural network model able to generating a 3D point cloud from a single image.Finally, we highlight in a last part the use of a multispectral mobile stereo system. We provide a public dataset to help the development of future methods and detail the development of a multi-spectral stereo drone prototype. We finally show how to use the images obtained by this prototype to build a 3D NDVI map and demonstrate its advantages over 2D maps that are used today., En viticulture comme dans de nombreux domaines, l'adoption de méthodes modernes est une étape essentielle dans l'optique de garantir la conformité aux normes de qualités. La télédétection, permettant de cartographier, analyser et traiter les vignobles est aujourd'hui une solution moderne pour gérer efficacement les parcelles de vignes. De plus, l'utilisation de capteurs multi-spectraux, notamment infrarouge et proche infrarouge, fournit des indicateurs clés dans l'aide au diagnostique d'une parcelle, notamment par la génération de carte d'indice de végétation par différence normalisée (NDVI). Enfin, les méthodes de reconstruction 3D offrent un réel apport pour le diagnostique d'un champ de vignes, puisqu'elles permettent d'effectuer des mesures précises directement depuis le modèle.Tandis que plusieurs solutions exploitent les différentes forces de ces méthodes, elles se contentent de traiter ces indicateurs séparément. Ainsi, il est possible d'obtenir une carte 3D à partir de capteurs spécifiques, l'on peut générer une carte NDVI 2D grâce aux images infrarouges et des images aériennes sont régulièrement prises à partir de drone ou de satellite pour analyser l'évolution d'un vignoble.L'objectif de cette thèse est de montrer qu'il est possible de combiner ces indicateurs afin de fournir une carte NDVI 3D d'une parcelle à partir d'images aériennes prises par un drone équipé d'une paire de capteurs.Nous proposons dans la première partie de ce manuscrit le contexte dans lequel se place notre étude. Nous introduisons la notion de viticulture de précision, et établissons un état de l’art des différentes méthodes de télédétection appliquées à l’étude de l’état phytosanitaire de la vigne.Nous nous intéressons dans une deuxième partie aux modèles 3D reconstruits par stéréo vision, et proposons différentes méthodes pour améliorer la qualité du nuage de points généré.Nous nous attarderons dans une troisième partie aux méthodes de reconstruction 3D à partir d'un système ne comportant qu'une seule caméra. Nous présentons dans cette partie une méthode pour optimiser le nombre d'images traitées pour alléger les solutions sur système embarqué ; ainsi qu'un modèle de réseau neuronal convolutif permettant de générer un modèle 3D à partir d'une seule image.Enfin, nous mettons en avant dans une dernière partie l'utilisation d'un système stéréo mobile multi-spectral. Nous mettons à disposition un jeu de données public aidant au développement de futures méthodes et détaillons le développement d'un prototype drone stéréo multi-spectral. Nous montrons enfin comment utiliser les images obtenues par ce prototype pour construire une carte NDVI 3D et démontrons ses avantages par rapport aux cartes 2D qui sont utilisées aujourd'hui.

Distribution patterns of the European fruit lecanium Parthenolecanium corni (Bouché) and of grapevine leafroll-associated virus-1 (GLRaV-1) and grapevine virus A (GVA) were monitored from 2003 to 2015 in a Riesling vine plot in the northeast of France. Virus spread was compared between two periods: 2003–2008 and 2009–2014. The percentage of infected vines increased from 54 to 78% for GLRaV-1 and from 14 to 26% for GVA. The spatial distribution of viruses and of P. corni was analysed using permutation tests and revealed an aggregative pattern. Virus distribution was not associated with the density of P. corni population on grapevines. However, GLRaV-1 and GVA spread mainly from initially infected vines. New GLRaV-1 and GVA infections were more frequent on vines near primarily infected vines, first anisotropically along the row, then between neighbouring rows. Virus spread was similar to those described in literature with grapevine mealybug species. This slow vine-to-vine progression suggests that P. corni was responsible for the virus spread, in accordance with the low mobility and low transmission capacities of its local population.

International audience; Viticulture has been essential for Oléron island, both from a socio-economic and landscape point of view, since at least the end of the Middle Ages. Oléron winegrowing sector is part of Cognac production basin and situated on the western fringes of the Protected Geographical Indication (PGI). This peripherical position compared to the most prestigious vintages of the PGI, and the hazards of a heavily export-oriented market, meant that Oléron wine growing lands get through large fluctuations : from 6,000 hectares in 19th century, which amouts to one third of the total surface of the island, to 750 hectares in 2010. During the second half of the 20th century, Oléron winegrowing sector had found an additional difficulty in the rapid growth of tourism, which provoked a tougher competition for land. It was confronted as well to production limitations through the uprooting of premiums. Facing these obstacles, stakeholders from Oléron winemaking sector have carried out economical adaptation efforts and protection of their access to land. We analyse their reaction in light of the evolutionist approach developed by economical geographers. Innovations mobilized through a learning process has seemed to allow the Oléron winegrowing stakeholders to soften the path dependency to the Cognac production basin capitalizing on the available territorial resources. Cooperation with local representatives, product and market diversification, upmarketing, and the spotlight put on the specificity of this terroir have contributed (re)territorialise winegrowing at the island level. This strategy seems to be bringing some stability to land property and better economical outputs to the sector.; La viticulture joue un rôle fondamental pour l’île d’Oléron, tant d’un point de vue socio-économique que paysager, et ce depuis au moins la fin du Moyen Âge. La filière viticole oléronaise s’inscrit dans le bassin de production du Cognac, en périphérie ouest de l’AOC. En situation de marginalité par rapport aux crus les plus prestigieux de l’appellation, soumis aux aléas d’un marché tourné vers l’exportation, le vignoble a occupé sur l’île une superficie très fluctuante : de 6 000 hectares dans la première moitié du xixe siècle, soit alors pratiquement un tiers du territoire oléronais, à 750 hectares au début des années 2010. Après la déstabilisation due au phylloxera autour de 1880, la viticulture oléronaise a dû composer avec le rapide développement du tourisme sur l’île et à la nouvelle concurrence qu’il impliquait sur le foncier dans la seconde moitié du xxe siècle. Elle a également été confrontée aux politiques d’arrachage pour réguler la production. Face à ces obstacles, les acteurs de la filière ont tenté d’adapter leurs modèles économiques et de protéger leur accès à la terre. Nous analysons ces dynamiques de résistance au prisme de l’approche évolutionniste développée en géographie économique. Le processus d’apprentissage et d’innovation qui a marqué la filière viticole oléronaise s’est traduit par une mise à profit des ressources territoriales disponibles, dans le but d’atténuer la dépendance de l’île au bassin de production du Cognac. La coopération avec les élus locaux, la diversification des produits et des marchés, la montée en gamme et la mise en avant d’un terroir singulier au sein de l’appellation, ont participé d’une (re)territorialisation de la viticulture et semblent aujourd’hui contribuer à la relative stabilité foncière et économique de la filière.

International audience; This work investigated the influence of grape variety, vineyard location, and grape harvest maturity, combined with different oxygen availability treatments, on red wine composition during bottle aging. Chemometric analysis of wine compositional data (i.e., wine color parameters, SO 2 , metals, and volatile compounds) demonstrated that the wine samples could be differentiated according to the different viticultural or bottle-aging factors. Grape variety, vineyard location, and grape maturity showed greater influence on wine composition than bottle-aging conditions. For most measured wine compositional variables, the evolution patterns adopted from the viticultural factors were not altered by oxygen availability treatment. However, contrasting evolution patterns for some variables were observed according to specific viticultural factors, with examples including dimethyl sulfide, phenylacetaldehyde, maltol, and β-damascenone for vineyard locations, 2-methylbutanal, 1,4-cineole, and linalool for grape variety, and methanethiol, methional, and homofuraneol for grape maturity.

International audience; Increasing landscape heterogeneity, both in terms of composition and configuration, can promote natural enemies and biological control in agricultural landscapes. However, relatively poor information exists about the effects of landscape heterogeneity on lacewings, which are a major group of predators. Furthermore, temporal changes of landscape effects on natural enemy dynamics remain largely unexplored.Here, we investigated how landscape composition and configuration affect lacewings and their biological control potential on leafhoppers. Lacewings and leafhoppers were sampled from April to July in 10 vineyards located in southwestern France. The vineyards were selected along a gradient of a proportion of semi-natural habitats in the landscape.The proportion of semi-natural habitats positively affected the abundance of adults and eggs, as well as species richness, of lacewings, alone or in interaction with the sampling month. Landscape configuration was never found to enhance abundance or species richness of lacewings. Finally, the predator-prey ratio increased through time but did not respond to landscape composition or configuration.Our study highlights that the proportion of semi-natural habitats increases both abundance and diversity of lacewings in vineyard landscapes but that this effect varies over time. This result indicates the need to assess the variability of landscape effects over time to maximize biological pest control services in agricultural landscapes.

Vine disease detection (VDD) is an important asset to predict a probable contagion of virus or fungi. Diseases that spreads through the vineyard has a huge economic impact, therefore it is considered as a challenge for viticulture. Automatic detection and mapping of vine disease in earlier stage can help to limit its impact and reduces the use of chemicals. This study deals with the problem of locating symptomatic areas in images from an unmanned aerial vehicle (UAV) using the visible and infrared domains. This paper, proposes a new method, based on segmentation by a convolutional neuron network SegNet and a depth map (DM), to delineate the asymptomatic regions in the vine canopy. The results obtained showed that SegNet combined with the depth information give better accuracy than a SegNet segmentation alone.

The current study validated a mechanistic model for Botrytis cinerea on grapevine with data from 23 independent Botrytis bunch rot (BBR) epidemics (combinations of vineyards × year) that occurred between 1997 and 2018 in Italy, France, and Spain. The model was operated for each vineyard by using weather data and vine growth stages to anticipate, at any day of the vine-growing season, the disease severity (DS) at harvest (severe, DS $ 15%; intermediate, 5 < DS < 15%; and mild, DS # 5%). To determine the ability of the model to account for latent infections, postharvest incubation assays were also conducted using mature berries without symptoms or signs of BBR. The model correctly classified the severity of 15 of 23 epidemics (65% of epidemics) when the classification was based on field assessments of BBR severity; when the model was operated to include BBR severity after incubation assays, its ability to correctly predict BBR severity increased from 65% to >87%. This result showed that the model correctly accounts for latent infections, which is important because latent infections can substantially increase DS. The model was sensitive and specific, with the false-positive and false-negative proportion of model predictions equal to 0.24 and 0, respectively. Therefore, the model may be considered a reliable tool for decision-making for BBR control in vineyards. © 2020 The American Phytopathological Society &nbsp

Aim: The recent availability of Sentinel-2 satellites has led to an increasing interest in their use in viticulture. The aim of this short communication is to determine performance and limitation of a Sentinel-2 vegetation index in precision viticulture applications, in terms of correlation and variability assessment, compared to the same vegetation index derived from an unmanned aerial vehicle (UAV). Normalised difference vegetation index (NDVI) was used as reference vegetation index.Methods and Results: UAV and Sentinel-2 vegetation indices were acquired for 30 vineyard blocks located in the south of France without inter-row grass. From the UAV imagery, the vegetation index was calculated using both a mixed pixels approach (both vine and inter-row) and from pure vine-only pixels. In addition, the vine projected area data were extracted using a support vector machine algorithm for vineyard segmentation. The vegetation index was obtained from Sentinel-2 imagery obtained at approximately the same time as the UAV imagery. The Sentinel-2 images used a mixed pixel approach as pixel size is greater than the row width. The correlation between these three layers and the Sentinel-2 derived vegetation indices were calculated, considering spatial autocorrelation correction for the significance test. The Gini coefficient was used to estimate variability detected by each sensor at the within-field scale. The effects of block border and dimension on correlations were estimated.Conclusions: The comparison between Sentinel-2 and UAV vegetation index showed an increase in correlation when border pixels were removed. Block dimensions did not affect the significance of correlation unless blocks were < 0.5 ha. Below this threshold, the correlation was non-significant in most cases. Sentinel-2 acquired data were strongly correlated with UAV-acquired data at both the field (R2 = 0.87) and sub-field scale (R2 = 0.84). In terms of variability detected, Sentinel-2 proved to be able to detect the same amount of variability as the UAV mixed pixel vegetation index.Significance and impact of the study: This study showed at which field conditions the Sentinel-2 vegetation index can be used instead of UAV-acquired images when high spatial resolution (vine-specific) management is not needed and the vineyard is characterised by no inter-row grass. This type of information may help growers to choose the most appropriate information sources to detect variability according to their vineyard characteristics.

International audience; Geographical indications (GIs) convey information about the place of production as a proxy for the attributes of agricultural products. We define the informational content of the GI proxy as its capacity to describe the tangible characteristics of production sites, instead of random noise or intangible factors from political bargaining about designation (i.e., lobbying effects). We estimate econometrically the informational content of wine‐related GIs for the Côte d'Or region of Burgundy, France. We show that GIs signal vineyard attributes with high precision, while we find some persistent bias from lobbying effects. We also study alternative classifications, from history and from simulations, which reveal a significant increase in the informational content of GIs over the last hundred years or so, and provide guidelines for better designated GIs in the future.

Vine introduction in Burgundy (east central France) two millennia ago is responsible for land use changes and increased soil erosion to which societies have tried to adapt. In this paper we seek to figure out the relationship between land uses, agricultural practices and geomorphic dynamics in the Mercurey terroir during the Late Holocene. The method employed is based on the analysis of sedimentary deposits observed in the valley bottom and along hillslopes. It is complemented by a pedoanthracological study derived from a trench excavated into a riverbank, in order to interpret the variability of the reconstituted sedimentary signal. Our results highlight two major stages of detritism over the last 2,800 years. At least from 800 cal. BC, frost heave screes (stored since the Late Pleistocene) are transported from the upper part of hillslopes to the valley bottom by high-energy geomorphic processes (e.g., solifluction flows). This sequence of coarse colluviums is associated with the development of an agro-pastoral landscape marked by an opening forest cover. A second phase begins after 1400 cal. AD. It is characterized by a fine sedimentation and a high concentration of vine charcoal. Indeed, wine-growing spread in the medieval landscape comes with the building of agricultural infrastructures. It leads to a decrease of sediment connections from the source areas to valley bottom. The coarser sediments are retained on the hillslopes, thus bringing out soil maintenance strategy. L’apparition de la vigne il y a deux millénaires en Bourgogne (Centre-Est de la France) est à l’origine de recompositions paysagères et d’une érosion des sols exacerbée à laquelle les sociétés ont tenté de s’adapter. Dans cet article nous cherchons à démontrer la relation entre les modes d’occupation du sol, les pratiques agricoles et les dynamiques géomorphologiques sur le terroir de Mercurey au cours de l’Holocène récent. La méthode privilégiée repose sur l’examen d’archives morpho-sédimentaires de fond de vallée et de versant. Elle est complétée par une étude pédoanthracologique, menée sur une coupe stratigraphique de berge, afin d’interpréter la variabilité du signal sédimentaire reconstitué. Les résultats soulignent deux phases majeures de détritisme au cours des 2 800 dernières années. Au moins à partir de 800 cal. BC, des éboulis cryoclastiques (stockés depuis la fin du Pléistocène) sont remaniés depuis les hauts de versant jusqu’au fond de vallée par des processus géomorphologiques gravitationnels (e.g., coulées de solifluxion). Ce colluvionnement grossier est associé au développement d’un paysage agro-pastoral marqué par l’ouverture du couvert forestier. Une seconde phase s’amorce après 1400 cal. AD. Elle est caractérisée par une sédimentation fine et une concentration élevée en charbons de vigne. En effet, la diffusion de la viticulture dans le paysage médiéval s’accompagne de la mise en place d’aménagements agricoles qui retiennent les sédiments les plus grossiers sur les versants, mettant ainsi en évidence une stratégie de gestion de la ressource en sol.

International audience; Soil available water capacity (SAWC) is a key soil function for plant growth. Classical SAWC characterization requires time consuming determinations of bulk density and specific soil moisture contents. Consequently, these data are extremely sparse in existing soil databases. Using surrogates of the vegetal response to characterize SAWC across a great number of sites constitutes a promising perspective. The carbon isotope ratio (δ13C) measured in a plant organ is largely known as an indicator of plant water status. The aim of the paper is to test δ13C as an indicator of SAWC in rainfed vineyard.δ13C values of grapes at harvest time were measured at 21 sites on the Languedoc vineyard plain with contrasting SAWC (33 to 308 mm) for four years (2015 to 2018) with contrasting annual precipitation (from 390 to 715 mm). The relationships between δ13C and SAWC determined using a classical approach (soil description, soil sampling and laboratory methods) were satisfactory for all years (RMSEs from cross validation were between 35 and 61 mm). Better relationships were obtained between δ13C and SAWC for years that showed a full winter recharge of SAWC (2015, 2017 and 2018). Averaging the δ13C measurements over such years provided an even better relationship (R2 = 0.85; RMSE 32 mm), which was successfully validated in distant sites on the Languedoc vineyard plain.This work demonstrated that δ13C can be considered as a simple and inexpensive surrogate for estimating SAWC. In addition to considerably increasing the density of SAWC measurements, the use of δ13C would lead to better consideration of the contribution of deep horizons in the case of perennial plants. Application of this isotopic technique to other agro-systems is required to better define the potential areas of use of δ13C.

Vineyards show some of the largest erosion rates reported in agricultural areas in Europe. Reported rates vary considerably under the same land use, since erosion processes are highly affected by climate, soil, topography and by the adopted soil management practices. Literature also shows differences in the effect of same conservation practices on reducing soil erosion from conventional, bare soil based, management. The Revised Universal Soil Loss Equation (RUSLE) is commonly adopted to estimate rates of water erosion on cropland under different forms of land use and management, but it requires proper value of soil cover and management (C) factors in order to obtain a reliable evaluation of local soil erosion rates. In this study the ORUSCAL (Orchard RUSle CALibration) is used to identify the best calibration strategy against long-term experimental data. Afterwards, ORUSCAL is used in order to apply the RUSLE technology from farm based information across different European wine-growing regions. The results suggest that the best strategy for calibration should incorporate the soil moisture sub-factor (Sm) to provide better soil loss predictions. The C factor, whose average values ranged from 0.012 to 0.597, presented a large spatial variability due to coupling with local climate and specific local management. The comparison across the five wine-growing regions indicates that for the soil protection management, permanent cover crop is the best measure for accomplishing sustainable erosion rates across the studied areas. Alternate and temporary cover crops, that are used in areas of limited water resources to prevent competition with vines, failed to achieve sustainable erosion rates, that still need to be addressed. This raises the need for a careful use of C values developed under different environmental conditions., This study was funded by the European BiodivERsA project VineDivers (https://short.boku.ac.at/vinedivers) through the BiodivERsA/FACCE JPI (2013–2014 joint call) for research proposals, with the national funders: Austrian Science Fund (grant numbers I 2044-/I 2043-/I 2042-B25 FWF), French National Research Agency (ANR), Spanish Ministry of Economy and Competitiveness (PCIN-2014-098), Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCDI) and Federal Ministry of Education and Research (BMBF/Germany). Also to the CNR Short Term Mobility Program 2016 for funding a stay at IAS-CSIC during which M.Biddoccu contributed to this study and the SHui project funded by the European Commission (GA 773903), which supported the final steps of the analysis presented in this manuscript.

Until the 15th century, during the medieval optimum, the climate of Mayenne was suitable to the existence of vineyards near towns and abbeys. During the XVI th century, climatic conditions remained suitable for viticulture with some financial return. During the XVII th and XVII th centuries, the Little Ice Age (cold winters, cold and humid springs and summers) appears as a limiting factor for a profitable viticulture except in the SE. The end of grapevine growing due to climate worsening occurs between 1690 and 1750 except in the SE. Global warming of the XX th and XXI st centuries would allow viticulture requiring a change in farming practices and land availability., Jusqu'au XV ème, pendant l'optimum médiéval, le climat permet en Mayenne l'existence de vignobles près des villes et des abbayes. Au XVI ème siècle, le climat encore clément autorise une certaine rentabilité. Aux XVII ème et XVII ème siècles, le PAG (hiver froids, printemps et été froids et humides) apparaît comme un facteur limitant pour une viticulture rentable sauf au SE. La fin des vignobles due à une aggravation du PAG se produit entre 1690 et 1750 sauf au SE. Le réchauffement climatique des XX ème et XXI ème siècles permettrait une viticulture sous réserve d'un changement des pratiques agricoles et de la disponibilité du foncier.

International audience

Vineyards in Brittany disappeared in the 20th century as a result of the phylloxera crisis and reappeared at the beginning of the 21st century under the impulse of individuals and associations of wine-lovers. Recently, professionals have been settling in Brittany with the aim of marketing wines. The process of renaissance in which this vineyard is extending is studied through the discourse of viticultural-related actors in Brittany and the regressive history method. If these actors mainly evoke the viticultural history to justify the process of rebirth in this marginal area of French viticulture, they also admit that climate change, and more specifically temperature increase, is beneficial for improving the quality of their production. This article particularly targets the vineyards in the Rance Valley in support of an excursion during this conference., Le vignoble breton a disparu au XXème siècle des conséquences de la crise phylloxérique pour réapparaître au début XXIème siècle sous l'impulsion de particuliers et d'associations passionnés d’oenologie. Depuis peu, des professionnels s'installent en Bretagne dans le but de commercialiser des vins bretons. Le processus de renaissance dans lequel ce vignoble grandit est étudié à travers le discours de quelques acteurs de la culture de la vigne en Bretagne et la méthode d’histoire régressive. Si l'histoire viticole de cet espace de marge de la viticulture française est majoritairement mise en avant par les acteurs interrogés pour expliquer le processus de renaissance, celui-ci s’inscrit dans un contexte de changement climatique avec des acteurs conscients que la hausse des températures permet d’améliorer la qualité de leur production. Cet article cible particulièrement le vignoble en Val de Rance en support d’une excursion lors de ce colloque.

International audience; Based on a review of the literature, the article proposes a state of the art centered on agroecology, a polysemic concept, in order to shed light on its scope for viticulture and its application within the framework of a project research aimed at understanding and building the agroecological transition in vineyards. Agroecology is considered alternately as a scientific discipline offering a systemic analysis by integrating human and social sciences, as a set of practices integrating the principles of ecology in agronomy (working with nature), or as a social movement. The scale of analysis has gradually been broadened from the level of agricultural plots to the level of territories, up to comprehensive approaches to the food system. Vine is a perennial monoculture for which the challenges of agroecological transition are particularly strong, in view of the strong pressure of pesticides applied for phytosanitary protection. This debate, which has become societal, implies an evolution of wine production systems in order to meet environmental and public health issues. In order to be able to construct and evaluate agroecological transition scenarios with professionals in the sector, we carried out a review of the literature which highlighted various agroecological practices in vineyards: preservation of biodiversity, reduction in the use of pesticides by regulation of pests and weeds, conservation of crop quality soils.. It also provides an opportunity to discuss the issues of broadening the meaning of the concept of agroecology in the current context. These elements are essential for identifying evaluation criteria in scenarios construction for the evolution of wine production conventional methods, as part of the ecological transition.; En s’appuyant sur une revue de la littérature, l’article propose un état de l’art centré sur l’agroécologie, concept polysémique, afin d’en éclairer la portée pour la viticulture et son application, dans le cadre d’un projet de recherche destiné à comprendre et construire la transition agroécologique dans les vignobles. L’agroécologie est tour à tour considérée comme une discipline scientifique proposant une analyse systémique en intégrant des sciences humaines et sociales, un ensemble de pratiques intégrant les principes de l’écologie en agronomie (travailler avec la nature), ou un mouvement social. L’échelle d’analyse a progressivement été élargie depuis le niveau de la parcelle agricole vers celui des territoires, jusqu’à des approches globales du système alimentaire. La vigne est une monoculture pérenne pour laquelle les enjeux de la transition agroécologique sont particulièrement importants eu égard notamment à la forte pression des pesticides appliqués en vue de la protection phytosanitaire. Ce débat, devenu sociétal, implique une évolution des systèmes de production viticole afin de satisfaire les enjeux environnementaux et de santé publique. Pour construire et évaluer des scénarios de transition agroécologique auprès des professionnels de la filière, nous avons réalisé une revue de la littérature qui a pu mettre en évidence différentes pratiques agroécologiques dans les vignobles : préservation de la biodiversité, baisse de l’usage des pesticides par une régulation des bioagresseurs et des adventices, conservation de la qualité des sols, adaptation au changement climatique. Elle permet également de discuter des enjeux d’élargissement de l’acception du concept d’agroécologie dans le contexte actuel. Ces éléments sont essentiels à l’identification de critères d’évaluation pour la construction de scénarios d’évolution des modes conventionnels de production viticole dans le cadre de la transition écologique.

International audience; The article reports on the prospective forum organized in 2019 by INRAE and InterLoire to explore the possible futures of Loire Valley vineyards in the context of climate change. 90 players in the wine sector expressed their perceptions of the impact of climate change in 2050, voted for an adaptation scénario and proposed levers for action to make it happen. The positions and proposals are analysed and compared with those of the forums held in six other wine regions, showing the specificities of the Loire Valley, in particular on the links with environmental issues.; L'article rend compte du forum de prospective organisé en 2019 par INRAE et InterLoire pour explorer les futurs possibles des vignobles du Val de Loire face au changement climatique. 90 acteurs de la filière ont exprimé leurs perceptions des conséquences du changement climatique en 2050, opté pour un scénario d’adaptation et proposé des leviers d’action pour qu’il se réalise. Les positions et propositions sont analysées et comparées à celles des forums réalisés dans six autres régions viticoles, montrant les spécificités du val de Loire, en particulier sur les liens avec les enjeux d’environnement.

International audience

International audience; Based on a review of the literature, the article proposes a state of the art centered on agroecology, a polysemic concept, in order to shed light on its scope for viticulture and its application within the framework of a project research aimed at understanding and building the agroecological transition in vineyards. Agroecology is considered alternately as a scientific discipline offering a systemic analysis by integrating human and social sciences, as a set of practices integrating the principles of ecology in agronomy (working with nature), or as a social movement. The scale of analysis has gradually been broadened from the level of agricultural plots to the level of territories, up to comprehensive approaches to the food system. Vine is a perennial monoculture for which the challenges of agroecological transition are particularly strong, in view of the strong pressure of pesticides applied for phytosanitary protection. This debate, which has become societal, implies an evolution of wine production systems in order to meet environmental and public health issues. In order to be able to construct and evaluate agroecological transition scenarios with professionals in the sector, we carried out a review of the literature which highlighted various agroecological practices in vineyards: preservation of biodiversity, reduction in the use of pesticides by regulation of pests and weeds, conservation of crop quality soils.. It also provides an opportunity to discuss the issues of broadening the meaning of the concept of agroecology in the current context. These elements are essential for identifying evaluation criteria in scenarios construction for the evolution of wine production conventional methods, as part of the ecological transition.; En s’appuyant sur une revue de la littérature, l’article propose un état de l’art centré sur l’agroécologie, concept polysémique, afin d’en éclairer la portée pour la viticulture et son application, dans le cadre d’un projet de recherche destiné à comprendre et construire la transition agroécologique dans les vignobles. L’agroécologie est tour à tour considérée comme une discipline scientifique proposant une analyse systémique en intégrant des sciences humaines et sociales, un ensemble de pratiques intégrant les principes de l’écologie en agronomie (travailler avec la nature), ou un mouvement social. L’échelle d’analyse a progressivement été élargie depuis le niveau de la parcelle agricole vers celui des territoires, jusqu’à des approches globales du système alimentaire. La vigne est une monoculture pérenne pour laquelle les enjeux de la transition agroécologique sont particulièrement importants eu égard notamment à la forte pression des pesticides appliqués en vue de la protection phytosanitaire. Ce débat, devenu sociétal, implique une évolution des systèmes de production viticole afin de satisfaire les enjeux environnementaux et de santé publique. Pour construire et évaluer des scénarios de transition agroécologique auprès des professionnels de la filière, nous avons réalisé une revue de la littérature qui a pu mettre en évidence différentes pratiques agroécologiques dans les vignobles : préservation de la biodiversité, baisse de l’usage des pesticides par une régulation des bioagresseurs et des adventices, conservation de la qualité des sols, adaptation au changement climatique. Elle permet également de discuter des enjeux d’élargissement de l’acception du concept d’agroécologie dans le contexte actuel. Ces éléments sont essentiels à l’identification de critères d’évaluation pour la construction de scénarios d’évolution des modes conventionnels de production viticole dans le cadre de la transition écologique.

International audience

International audience; The land issue in viticulture has obvious particularities for analysts in the sector. This chapter focuses on the issues of installation of vines, justifying the legal forms that support it. It explains the main mechanisms for setting prices for vinegrowing land and discusses regulatory framework in terms of public support, conditions of access, and financing. The chapter presents details about the institutions and organizations that have emerged from land policy at both national and European levels, determining the price and conditions of purchase. The basic amount of the installation grant for young farmers varies according to three criteria: the agro‐ecological dimension of the project; the difficulties of installation encountered when taking over outside the familial framework; and the project's potential to generate added value and employment. For viticulture, the price of land is a key factor in the establishment of young farmers or the transfer of winegrowing businesses.

Botrytis bunch rot (BBR) is a major disease occurring in vineyards worldwide. Its control is still largely based on the use of synthetic fungicide sprayings at predetermined intervals, which often produces negative residues in grapes and wines that may affect the environment and/or human health. To rationalize BBR management, disease risk indicators were developed and evaluated in a set of field experiments carried out between 2010 and 2019 in France and Chile. Key indicators include early grapevine vegetative growth, i.e. ground-based normalized difference vegetation index (NDVI), and the potential berry susceptibility to Botrytis cinerea, which is driven by tannin content in the skin. Under these contrasting weather and cropping conditions, regression analyses, including weather information, showed a highly significant positive correlation between the early NDVI, measured at berry pea size stage, and BBR incidence or severity at harvest, whereas the opposite was demonstrated for tannin content in the berry skin measured at an early herbaceous fruit stage. The exponential relationship between the final disease severity and the early NDVI allowed us to identify a possible threshold NDVI value, i.e. between 0.5 and 0.6, under which the BBR severity should be lower or close to 5% at harvest (BBR tolerance threshold for wine quality). Accordingly, in a leaf-removal vineyard experiment in France, the NDVI level at berry pea size stage was strictly controlled to correspond to three different increasing index values: 0.45, 0.60, and 0.78. Following this increase in NDVI, a significant increase in final BBR severity was noticeable, i.e. 2.4%, 6.6% and 9.9%, respectively. Very interestingly, the NDVI increase was also related to a significant decrease in the tannin content in the skin of herbaceous berries at veraison, from 47 to 22 mg tannin/g skin. All regression analyses explaining BBR development were highly significant, showing the weather conditions before harvest as the primary factor. They also show that some of the disease risk indicators chosen, especially early NDVI, could be used in the future as tools in decision support systems for deciding to spray and/or scheduling optimized fungicide applications during the season.

International audience; This collective work highlights the new challenges facing the French wine industry and the issues that arise from it. Written on the basis of academic work and field studies, conducted by a group of Montpellier academics in Economics and Management Sciences (Groupe Montpellier Vin), this book presents recent and original research results and raises the key issues related to finance, strategy, international management and marketing. Professionals in the sector, academics, students and wine enthusiasts will find up-to-date information, in-depth analyses and above all, an invitation to a stimulating debate on the prospects of this traditional, yet innovative sector.

International audience; The necessity to adapt to climate change is even stronger for grapevine than for other crops, because grape berry composition—a key determinant of fruit and wine quality, typicity and market value— highly depends on “terroir” (complete natural environment), on vintage (annual climate variability), and on their interactions. In the same time, there is a strong demand to reduce the use of pesticides. Thus, the equation that breeders and grape growers must solve has three entries that cannot be dissociated: adaptation to climate change, reduction of pesticides, and maintenance of wine typicity. Although vineyard management may cope to some extent to the short–medium-term effects of climate change, genetic improvement is necessary to provide long-term sustainable solutions to these problems. Most vineyards over the world are planted using vines that harbor two grafted plants’ genomes. Although this makes the range of interactions (scion-atmosphere, rootstock-soil, scion-rootstock) more complex, it also opens up wider possibilities for the genetic improvement of either or both the grafted genotypes. Positive aspects related to grapevine breeding are as follows: (a) a wide genetic diversity of rootstocks and scions that has not been thoroughly explored yet; (b) progress in sequencing technologies that allows high-throughput sequencing of entire genomes, faster mapping of targeted traits and easier determination of genetic relationships; (c) progress in new breeding technologies that potentially permit precise modifications on resident genes; (d) automation of phenotyping that allows faster and more complete monitoring of many traits on relatively large plant populations; (e) functional characterization of an increasing number of genes involved in the control of development, berry metabolism, disease resistance, and adaptation to environment. Difficulties involve: (a) the perennial nature and the large size of the plant that makes field testing long and demanding in manpower; (b) the low efficiency of transformation, regeneration and small size of breeding populations; (c) the complexity of the adaptive traits and the need to define more clearly future ideotypes; (d) the lack of shared and integrative platforms allowing a complete appraisal of the genotype-phenotype-environmental links; (e) legal, market and consumer acceptance of new genotypes. The present chapter provides an overview of suitable strategies and challenges linked to the adaptation of viticulture to a changing environment.

Nowadays politics, people and environmentalists would like agriculture to reduce its uses of pesticides because they have doubts on their harmlessness for people and environment. Vitis vinifera are sensitive to two main diseases, powdery mildew and downy mildew, that have been imported from the US during the XIX century. To protect the quality of thre grapes and to avoid yield losses winegrower must spray their vineyard several times a year. Recently several tools have been designed to help winegrower in reducing the use of pesticides and few of them have been challenged on Louis Latour’s vineyard in diferent experiments. Optidose adjusts the quantity of pesticide considering the vine leaf volume, the epidemic of the diseases and the sensitivity of the plants. It gives good results in protecting the vineyard and also in reducing the use of pesticides. Decitrait is an other tool that has been tested. Using the meteo data it predicts when the contaminations can happen. The predictions made were good and the tool seems to be efective. More and more supports are available to help winegrower in enhancing the way they produce. Their evaluations are conclusive and show good results in terms of crop protection and to reduce the use of pesticides.; Le contexte actuel, qu’il soit d’ordre politique, sociétal ou bien environnemental, souhaite voir une réduction de l’usage des produits phytopharmaceutiques en agriculture. En effet, ces derniers sont montrés du doigt pour leurs effets néfastes sur la biodiversité ainsi qu’au niveau de la santé publique. Cependant, les Vitis vinifera, vigne européennes plébiscitées dans le monde entier pour la qualité des vins qu’elles produisent, sont sensibles à deux maladies majeures qui ont été importées en Europe au XIXe siècle : le mildiou et l’oïdium. Ces deux maladies, si elles ne sont pas maîtrisées entraînent des pertes à la fois qualitatives et quantitatives sur la récolte. Ainsi, chaque année les viticulteurs sont obligés de mettre en place une lutte fongicide importante contre ces deux pathogènes. Au cours des dernières années, la filière viticole s’est saisie de la question afin d’optimiser les traitements fongicides. Des travaux ont été menés sur le vignoble d’approvisionnement de Louis Latour Ardèche afin d’évaluer la pertinence de certains des nouveaux outils développés. Optidose vise à moduler la dose de fongicide appliquée en fonction : du volume foliaire, de la pression parasitaire et de la sensibilité de la vigne. Cet outil a montré de très bons résultats en termes de réduction de dose et de protection sanitaire. Un deuxième outil, Décitrait, identifie quant à lui les périodes à risque vis-à-vis des maladies cryptogamiques et s’est révélé performant dans la pratique. Ainsi, petit à petit, des solutions opérationnelles deviennent accessible afin d’aider les viticulteurs à réduire leur usage de pesticides.

Vineyard monoculture poses a threat to biodiversity by occupying key habitats and simplifying ecological communities. Landscape simplification is known as a cause of insect and disease outbreaks for a few decades now. Changes that will not radically modify the monoculture nature of agrosystems may moderate negative impacts temporarily. Though, for real resiliency and durable benefits, radical agroecological measures are needed to strengthen farming resiliency. Diversification of agrosystems in the form of biodiversity-wise designed systems such as agroforestry are such measures. In vineyard systems, cover crop is often the only biodiversity feature part of the farming strategy. A broader range of Green Infrastructure (GI, non-vine vegetation and water-systems) such as insectaries and hedgerows would be necessary for a systemic approach to better-balanced agrosystems, using predatorial insects to fight pest and shrubs for regulating airflow.While a great deal is known about the benefits of incorporating more biodiversity to mitigate negative impacts of monocultural farming, and to provide an increase of ecosystem services (ES), little study of its implementation within vineyards exists. Nor much study about whether vineyard owners purposely design for greening and how. Biodiversity as a tool does not seem to be part of the planting process even in new wine regions.Semi-structured long interviews and GI mapping are used in Waipara Valley wine region to understand how winegrowers make decisions about the incorporation of GI in vineyards and to locate them. Also, to increase farmer awareness, results will be shared in a comprehensive and informative way with the interviewees.The study shows vineyard design process doesn't include GI, and the use of farm maps is very limited. GI presence is low and mainly limited to areas that aren't suitable for production. Properties show three types of design: conventionally designed homogeneous vineyards, conventionally designed farms with the use of hedgerow and more diverse vineyard farms. The cellar door or Airbnb presence on properties increases the GI whereas certification or vineyard size are not major factors. Providing managers with a personal map and a biodiversity assessment as feedback is aiming at increasing their awareness on their biodiversity and give them a designing tool. As patches on each property are too limited to support a real biodiversity network, it would be good to work on a landscape scale with the involvement of regional and wine organisations to bind neighbouring properties together and build a biodiversity network based on waterways.; La monoculture viticole menace la biodiversité en occupant des habitats clés et en simplifiant les communautés écologiques. La simplification des paysages est reconnue comme étant une raison des invasions d'insectes ou de maladies depuis plusieurs dizaines d'années maintenant. Des changements qui ne modifient pas radicalement la nature monoculturale des agrosystèmes peuvent temporairement réduire les impacts négatifs, mais pour une réelle résilience et des bénéfices durables, des mesures agro-écologiques radicales sont nécessaires. La diversification réfléchie des écosystèmes incluant un design de la biodiversité comme l'agroforesterie est un exemple. Dans les systèmes viticoles, l'utilisation de plantes de couverture est souvent le seul outil de management basé sur la biodiversité. Un plus large panel d’Éléments de Biodiversité (végétation autre que la vigne ainsi que le réseau d’eau, appelées Green Infrastructure (GI) en anglais), comme des réserves d’insectes ou haies, doit être utilisé comme outil de travail pour une approche systémique allant vers des agrosystèmes plus équilibrés, utilisant des insectes prédateurs pour combattre les parasites et des buissons pour réguler les flux d'air.Alors que les connaissances sont nombreuses sur les bénéfices de l'incorporation de plus de biodiversité pour diminuer les impacts négatifs de la monoculture, ainsi que pour fournir des services écosystémiques, seulement peu d'études existent sur sa mise en place dans les vignobles. De même, très peu d'études cherchent à comprendre si le design de la biodiversité dans les vignes résulte d'une action volontaire ou alors, si et comment, il est planifié. La biodiversité en tant qu'outil ne semble pas faire partie du processus de plantation même dans les régions viticoles récentes.Des interviews longues semi-structurées ainsi que la cartographie des GI sont les méthodes utilisées dans la région viticole de Waipara pour comprendre comment les vignerons choisissent la localisation de la biodiversité et pour identifier les GI présentes dans les vignes. Aussi, pour augmenter la prise de conscience sur le sujet, les résultats seront diffusés de façon compréhensive et informative avec les interviewés.Cette étude montre que le processus de design des vignobles n'inclut pas l'incorporation de GI et l'utilisation de cartes des vignobles est très limitée. La présence de GI est faible et principalement limitée à des zones non exploitables pour une production viticole. Trois types de design ont été identifiés : des vignobles conventionnels homogènes, des fermes conventionnelles utilisant des haies, et des fermes plus diversifiées. La présence d'un caveau de dégustation ou d'un Airbnb sur la propriété augmente la présence de biodiversité alors que la certification ou la taille du vignoble n'est pas un facteur explicatif majeur. Fournir des cartes et une évaluation personnalisée de la biodiversité sur les domaines vise à augmenter la conscience des vignerons vis-à-vis de leur biodiversité et à leur donner des outils de planification. Puisque la biodiversité présente sur chaque propriété est insuffisante pour former un réel réseau, il serait judicieux de travailler à l’échelle des paysages avec l’implication d’acteurs régionaux ainsi que d’institutions viticoles, pour lier les propriétés voisines entre elles et construire un réseau de végétation basé sur les cours d’eau.

Pesticides have been associated with various pathologies, and there is growing evidence of pesticide presence in domestic environments. However, most available studies focused on a limited number of pesticides or households, and few have been conducted in Europe. We aimed to assess indoor pesticide contamination by screening the prevalence of 276 pesticides and ten pesticide metabolites, in French households from different agricultural and urban areas. We sampled indoor dust from 239 households in 2012, proximate to orchards (n = 69), cereals (n = 66) and vineyard (n = 68) crops, or from urban area (n = 36). we used cellulose wipes moistened with isopropanol and polypropylene dust traps to collect recent (7 and 30 days, respectively) and settled dust (6 months). Overall, 125 pesticides and piperonyl butoxide were detected at least once in households, mostly at low prevalence: 97 in recent dust, and 111 in settled dust. In recent dust, the most prevalent compounds were o-phenylphenol (168 households, 70%), pentachlorophenol (86, 36%), and piperonyl butoxide (82, 34%). In addition to agricultural pesticides, we found a high proportion of domestic and banned compounds in recent and settled house dust. Several pesticides were identified in house dust, from different pesticide groups and sources. Our results suggest that domestic usage and persistence of banned pesticides may contribute substantially to indoor pesticide contamination. Graphical abstract 97 pesticides detected in households' recent indoor dust.

International audience; The effect of soil on wine composition and flavor is controversially discussed in viticulture. Mineral nutrition of the grapevine is one possibility for an influence of soil chemistry on winemaking. However, effects of soil chemistry are difficult to isolate from other physical and biological factors.Here two winegrowing plots in the Soave region (Italy) were investigated, lying side by side on contrasted soil types. Factors that influenced soil formation and characterize soil chemistry and mineralogy were determined. The influence of soil type on the elemental composition (Mg, Al, P, S, K, Ca, Mn, Fe, Cu, Zn, Sr, Mo and Ba) of leaves and grapes was studied. Carbon isotope ratios were measured to evaluate water stress. Radiogenic Sr and stable Cu isotope ratios were studied to identify the influence of different bedrocks and better understand the mechanisms involved in the soil-to-grape continuum.Even though the morphology of soils is different, chemical characteristics are similar in both vineyard plots. Nevertheless, Sr isotope ratios of horizons of both soils show influence of different bedrocks on their genesis. The composition of grapevine plants is similar between both plots even though there is a tendency for higher elemental contents on more calcareous soil. Finally, isotope ratios show that different mechanisms control Cu and Sr in plant: Cu seems to be controlled by regulation mechanisms of the plants whereas Sr is absorbed in ratios similar to the soil, reflecting the different geological origins.

BACKGROUND Plasmopara viticola control in organic viticulture requires copper-based fungicides with harmful effects on health and the environment. Plant extracts represent a biorational eco-friendly alternative to copper. The aim of this study was to evaluate the potential of stilbenoid-rich grape cane extract (GCE) against downy mildew on three cultivars over 3 years following natural downy mildew infection. RESULTS Over all field trials, GCE treatments showed an average reduction in disease incidence of -35% and -38% on leaves and clusters, respectively. The average reduction in disease severity was -35% and -43% on leaves and clusters, respectively. Under artificial downy mildew infection, GCE efficacy corresponded to 1 g L-1 of copper. Neither phytotoxicity nor adverse effects on auxiliary fauna were observed after treatment with GCE. CONCLUSION Because few or no biocontrol agents are active alone against P. viticola, GCE is a promising alternative to copper-based fungicides. Grape canes, an abundant by-product of viticulture, have great potential for valorization as a biocontrol agent for sustainable viticulture. © 2018 Society of Chemical Industry.

International audience; Viticultural byproducts are known to contain high-value compounds such as stilbenes. The wine sector in Savoie Mont Blanc region (France) generates a great amount of waste, including grape canes and grapevine stocks that remain unvalued. Herein, the potential of the most widespread grapevine varieties in the Savoie Mont Blanc territory, Jacquère and Mondeuse, as sources of two stilbenes, trans-resveratrol (Rsv) and trans-ε-viniferin (Vf), was investigated for the first time. Using the reported extraction technique, the present work focused on several pre-extraction parameters influencing the extraction efficiency, including grapevine variety, age of vines, time of material storage, and particle size of the woody material. This work revealed important Rsv and Vf contents in Jacquère residues of 1681–6124 and 1620–6667 mg·kgdw–1, respectively, whereas for the Mondeuse variety, the targeted molecule yields were 1724–4636 and 1713–5322 mg·kgdw–1, respectively. These results are promising when compared with the well-known high stilbenes levels in Pinot Noir and Gewurztraminer varieties but also highlight a considerable variability depending on the applied pre-extraction parameters.