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Quantifying healthy and degraded inner tissues in plants is of great interest in agronomy, for example, to assess plant health and quality and monitor physiological traits or diseases. However, detecting functional and degraded plant tissues in-vivo without harming the plant is extremely challenging. New solutions are needed in ligneous and perennial species, for which the sustainability of plantations is crucial. To tackle this challenge, we developed a novel approach based on multimodal 3D imaging and artificial intelligence-based image processing that allowed a non-destructive diagnosis of inner tissues in living plants. The method was successfully applied to the grapevine (Vitis vinifera L.). Vineyard's sustainability is threatened by trunk diseases, while the sanitary status of vines cannot be ascertained without injuring the plants. By combining MRI and X-ray CT 3D imaging with an automatic voxel classification, we could discriminate intact, degraded, and white rot tissues with a mean global accuracy of over 91%. Each imaging modality contribution to tissue detection was evaluated, and we identified quantitative structural and physiological markers characterizing wood degradation steps. The combined study of inner tissue distribution versus external foliar symptom history demonstrated that white rot and intact tissue contents are key-measurements in evaluating vines' sanitary status. We finally proposed a model for an accurate trunk disease diagnosis in grapevine. This work opens new routes for precision agriculture and in-situ monitoring of tissue quality and plant health across plant species.

Chimerism is the phenomenon when several genotypes coexist in a single individual. Used to understand plant ontogenesis they also have been valorised through new cultivar breeding. Viticulture has been taking economic advantage out of chimeras when the variant induced an important modification of wine type such as berry skin colour. Crucial agronomic characters may also be impacted by chimeras that aren't identified yet. Periclinal chimera where the variant has entirely colonised a cell layer is the most stable and can be propagated through cuttings. In grapevine, leaves are derived from both meristem layers, L1 and L2. However, lateral roots are formed from the L2 cell layer only. Thus, comparing DNA sequences of roots and leaves allows chimera detection. In this study we used new generation Hifi long reads sequencing, recent bioinformatics tools and trio-binning with parental sequences to detect periclinal chimeras on 'Merlot' grapevine cultivar. Sequencing of cv. 'Magdeleine Noire des Charentes' and 'Cabernet Franc', the parents of cv. 'Merlot', allowed haplotype resolved assembly. Pseudomolecules were built with a total of 33 to 47 contigs and in few occasions a unique contig for one chromosome. This high resolution allowed haplotype comparison. Annotation was transferred from PN40024 VCost.v3 to all pseudomolecules. After strong selection of variants, 51 and 53 'Merlot' specific periclinal chimeras were found on the Merlot-haplotype-CF and Merlot-haplotype-MG respectively, 9 and 7 been located in a coding region. A subset of positions was analysed using Molecular Inversion Probes (MIPseq) and 69% were unambiguously validated, 25% are doubtful because of technological noise or weak depth and 6% invalidated. These results open new perspectives on chimera detection as an important resource to improve cultivars through clonal selection or breeding.

Background and Aims: Condensed tannins, responsible for berry and wine astringency, may have been selected during grapevine domestication. This work examines the phylogenetic distribution of condensed tannins throughout the Vitaceae phylogenetic tree. Methods: Green berries and mature leaves of representative true-to-type members of the Vitaceae were collected before 'véraison', freeze-dried and pulverized, and condensed tannins were measured following depolymerization by nucleophilic addition of 2-mercaptoethanol to the C4 of the flavan-3-ol units in an organic acidic medium. Reaction products were separated and quantified by ultrahigh pressure liquid chromatography/diode array detection/mass spectrometry. Key Results and Conclusions: The original ability to incorporate epigallocatechin (EGC) into grapevine condensed tannins was lost independently in both the American and Eurasian/Asian branches of the Vitaceae, with exceptional cases of reversion to the ancestral EGC phenotype. This is particularly true in the genus Vitis, where we now find two radically distinct groups differing with respect to EGC content. While Vitis species from Asia are void of EGC, 50 % of the New World Vitis harbour EGC. Interestingly, the presence of EGC is tightly coupled with the degree of leaf margin serration. Noticeably, the rare Asian EGC-forming species are phylogenetically close to Vitis vinifera, the only remnant representative of Vitis in Eurasia. Both the wild ancestral V. vinifera subsp. sylvestris as well as the domesticated V. vinifera subsp. sativa can accumulate EGC and activate galloylation biosynthesis that compete for photoassimilates and reductive power.

In many areas of the world, maintaining grapevine production will require adaptation to climate change. While rigorous evaluations of adaptation strategies provide decision makers with valuable insights, those that are published often overlook major constraints, ignore local adaptive capacity, and suffer from a compartmentalization of disciplines and scales. The objective of our study was to identify current knowledge of evaluation methods and their limitations, reported in the literature. We reviewed 111 papers that evaluate adaptation strategies in the main vineyards worldwide. Evaluation approaches are analyzed through key features (e.g., climate data sources, methodology, evaluation criteria) to discuss their ability to address climate change issues, and to identify promising outcomes for climate change adaptations. We highlight the fact that combining adaptation levers in the short and long term (location, vine training, irrigation, soil, and canopy management, etc.) enables local compromises to be reached between future water availability and grapevine productivity. The main findings of the paper are three-fold: (1) the evaluation of a combination of adaptation strategies provides better solutions for adapting to climate change; (2) multi-scale studies allow local constraints and opportunities to be considered; and (3) only a small number of studies have developed multi-scale and multi-lever approaches to quantify feasibility and effectiveness of adaptation. In addition, we found that climate data sources were not systematically clearly presented, and that climate uncertainty was hardly accounted for. Moreover, only a small number of studies have assessed the economic impacts of adaptation, especially at farm scale. We conclude that the development of methodologies to evaluate adaptation strategies, considering both complementary adaptations and scales, is essential if relevant information is to be provided to the decision-makers of the wine industry.

Les enjeux du changement climatique sont souvent présentés à l'échelle globale, alors que l'adaptation nécessite des connaissances sur ses impacts à une échelle locale. Cet article propose une démarche originale combinant modélisation numérique et démarche participative au sein d'un bassin viticole méditerranéen. Elle a pour objectifs (i) d'utiliser les projections climatiques avec des acteurs, (ii) de quantifier les impacts du changement climatique selon les systèmes de production, et (iii) d'engager des réflexions sur les adaptations à mettre en oeuvre. Les résultats de simulation ont montré une vulnérabilité accrue des systèmes viticoles à haut rendement, comparés aux systèmes en AOP. Cependant, des incertitudes subsistent concernant l'occurrence des évènements extrêmes et l'effet de températures élevées. Les adaptations envisagées s'appuient sur ces résultats et sont enrichies des connaissances expertes.

Grapevine is one of the most economically important fruit crops due to the high value of its fruit and its importance in winemaking. The current decrease in grape berry quality and production can be seen as the consequence of various abiotic constraints imposed by climate changes. Specifically, produced wines have become too sweet, with a stronger impression of alcohol and fewer aromatic qualities. Potassium is known to play a major role in grapevine growth, as well as grape composition and wine quality. Importantly, potassium ions (K+) are involved in the initiation and maintenance of the berry loading process during ripening. Moreover, K+ has also been implicated in various defense mechanisms against abiotic stress. The first part of this review discusses the main negative consequences of the current climate, how they disturb the quality of grape berries at harvest and thus ultimately compromise the potential to obtain a great wine. In the second part, the essential electrical and osmotic functions of K+, which are intimately dependent on K+ transport systems, membrane energization, and cell K+ homeostasis, are presented. This knowledge will help to select crops that are better adapted to adverse environmental conditions.

Grapevine breeding needs to address two main issues over the next few years: reducing pesticide use and adaptating to climate change. If the selection of new resistant grapevine cultivars has been accelerated, breeding remains a long and costly process for a perennial species such as grapevine. That is why I tested and compared different methodologies for optimizing the breeding of new grapevine varieties. The first is genomic prediction (GP), which relies on the use of molecular markers to train a model to predict genetic values. The second is phenomic prediction (PP), which relies on the use of spectra measured on plant tissues, which is cheaper and more high-throughput than genotyping. I used GP and PP under different configurations to evaluate their interest in breeding programs. For that, I used three grapevine populations with contrasted relatedness, both genotyped and phenotyped. First, I compared univariate and multivariate GP models in a bi-parental population (N=188), on 14 traits related to drought. Multivariate methods did not perform better than univariate ones, and ranking between methods depended on the genetic architecture and heritability of the trait. Secondly, I tested across-population GP (a more applicable configuration for breeding) for 15 traits, by training the prediction model in a diversity panel (N=277) and using 10 bi-parental families of a half-diallel (N=622) as validation sets. For that, I first predicted the average genetic value of each family (for the first selection step of future crosses to be made) and then the genetic values of individuals within each family (for the second selection step of offspring within crosses once they have been realized). Prediction accuracy for these two steps appeared to be satisfying for the application of GP in breeding programs, compared to within-population prediction accuracy. Finally, I tested for the first time the application of PP in grapevine, by using near-infrared spectra measured on wood a

Les enjeux du changement climatique sont souvent présentés à l'échelle globale, alors que l'adaptation nécessite des connaissances sur ses impacts à une échelle locale. Cet article propose une démarche originale combinant modélisation numérique et démarche participative au sein d'un bassin viticole méditerranéen. Elle a pour objectifs (i) d'utiliser les projections climatiques avec des acteurs, (ii) de quantifier les impacts du changement climatique selon les systèmes de production, et (iii) d'engager des réflexions sur les adaptations à mettre en oeuvre. Les résultats de simulation ont montré une vulnérabilité accrue des systèmes viticoles à haut rendement, comparés aux systèmes en AOP. Cependant, des incertitudes subsistent concernant l'occurrence des évènements extrêmes et l'effet de températures élevées. Les adaptations envisagées s'appuient sur ces résultats et sont enrichies des connaissances expertes.

In many areas of the world, maintaining grapevine production will require adaptation to climate change. While rigorous evaluations of adaptation strategies provide decision makers with valuable insights, those that are published often overlook major constraints, ignore local adaptive capacity, and suffer from a compartmentalization of disciplines and scales. The objective of our study was to identify current knowledge of evaluation methods and their limitations, reported in the literature. We reviewed 111 papers that evaluate adaptation strategies in the main vineyards worldwide. Evaluation approaches are analyzed through key features (e.g., climate data sources, methodology, evaluation criteria) to discuss their ability to address climate change issues, and to identify promising outcomes for climate change adaptations. We highlight the fact that combining adaptation levers in the short and long term (location, vine training, irrigation, soil, and canopy management, etc.) enables local compromises to be reached between future water availability and grapevine productivity. The main findings of the paper are three-fold: (1) the evaluation of a combination of adaptation strategies provides better solutions for adapting to climate change; (2) multi-scale studies allow local constraints and opportunities to be considered; and (3) only a small number of studies have developed multi-scale and multi-lever approaches to quantify feasibility and effectiveness of adaptation. In addition, we found that climate data sources were not systematically clearly presented, and that climate uncertainty was hardly accounted for. Moreover, only a small number of studies have assessed the economic impacts of adaptation, especially at farm scale. We conclude that the development of methodologies to evaluate adaptation strategies, considering both complementary adaptations and scales, is essential if relevant information is to be provided to the decision-makers of the wine industry.

Grapevine is one of the most economically important fruit crops due to the high value of its fruit and its importance in winemaking. The current decrease in grape berry quality and production can be seen as the consequence of various abiotic constraints imposed by climate changes. Specifically, produced wines have become too sweet, with a stronger impression of alcohol and fewer aromatic qualities. Potassium is known to play a major role in grapevine growth, as well as grape composition and wine quality. Importantly, potassium ions (K+) are involved in the initiation and maintenance of the berry loading process during ripening. Moreover, K+ has also been implicated in various defense mechanisms against abiotic stress. The first part of this review discusses the main negative consequences of the current climate, how they disturb the quality of grape berries at harvest and thus ultimately compromise the potential to obtain a great wine. In the second part, the essential electrical and osmotic functions of K+, which are intimately dependent on K+ transport systems, membrane energization, and cell K+ homeostasis, are presented. This knowledge will help to select crops that are better adapted to adverse environmental conditions.

Le mildiou de la vigne est causé par Plasmopara viticola, un oomycète parasite obligatoire, originaire de l’Amérique du Nord. Ce pseudochampignon se développe sur tous les organes verts en croissance de la vigne et ne s’attaque pas aux tissus aoûtés. Lorsque les conditions sont favorables, les épidémies du mildiou de la vigne entraînent des destructions partielles ou totales des feuilles et des baies, l’avortement ou le dessèchement des fleurs et l’affaiblissement des ceps. Plusieurs méthodes de lutte ont été utilisées contre cette maladie, mais la plus efficace à nos jours reste les applications de fongicides chimiques couplées aux outils d’aides à la décision. Ces outils d’aide à la décision reposent sur une bonne compréhension de l’interaction entre la plante, l’agent pathogène et l’environnement. Il existe 5 clades de P. viticola à travers le monde. Seulement deux des 5 clades sont prévalents dans l’est du Canada. Des études préliminaires ont permis de déterminer que les épidémies du mildiou de la vigne causée par le clade riparia débutent 2-3 semaines avant celles du clade aestivalis et que les concentrations aériennes saisonnières des sporanges du clade aestivalis sont supérieures à celle du clade riparia. Avec ces nouvelles informations, il devient judicieux de se poser les questions suivantes : est-ce que ces deux clades ont la même épidémiologie ? Est-ce que les programmes de gestion du mildiou de la vigne devraient être adaptés à chacun des clades ? Ce projet de doctorat avait pour objectif de comparer l’épidémiologie des deux clades de Plasmopara viticola (clade riparia et clade aestivalis) prévalents dans l’est du Canada, dans le but de comprendre et d’expliquer pourquoi les épidémies du clade riparia débutent avant celles du clade aestivalis alors que les concentrations aériennes saisonnières des sporanges du clade aestivalis sont supérieures à celles du clade riparia. Pour atteindre cet objectif, l’influence de la température sur l’agressivité des deux

Mondialement, la culture de la vigne (Vitis spp.) revêt une grande importance tant au niveau économique que social. En 2018, avec approximativement 7,4 millions d’hectares et 77,8 millions de tonnes métriques de raisins, il s’agit d’une des plus grandes cultures fruitières au monde. Au Canada seulement, l’industrie du vin a rapporté 9 milliards de dollars et créée 37 000 emplois en 2015. Près de cent agents intra-cellulaires infectieux sont retrouvés chez la vigne: virus (86), viroïdes (6), phytoplasmes (8), et bactéries transmises par un insecte via le xylème (1). Cela en fait la culture avec le plus grand nombre de pathogènes intracellulaires. Ces infections peuvent causer une diminution du rendement, de la qualité du raisin ainsi que de la vigueur des plants de vignes. En outre, la production de raisins engendre l’une des plus grandes consommations de pesticides dans l’agriculture mondiale. Des nématicides et des insecticides sont utilisés pour contrôler les vecteurs viraux. De nos jours, les principales stratégies pour contrôler la propagation virale sont la sélection sanitaire, l’élimination des virus et les programmes de certification. Cependant, ces stratégies ont un impact limité. En effet, pour une grande partie de ces virus, le vecteur n’est pas connu et l’efficacité des produits chimiques pour contrôler la dynamique des vecteurs est nulle pour les nématicides et est remise en question pour les insecticides. Actuellement, la diversité virale et le contrôle phytosanitaire sont biaisés en faveur des virus causant des infections symptomatiques sur les plantes cultivées. Les virus latents, cryptiques ou asymptomatiques représentent respectivement 7% et 4% de ceux classifiés pour les plantes. Selon des recherches en métagénomique, les infections asymptomatiques semblent plus courantes qu’initialement imaginées. Développer une technique de caractérisation du virome (ensemble des virus qui peuplent un environnement donné) robuste contribuerait à solidifier les pr

The trait‐based approach can address questions in order to understand how the functioning of organisms scales up to that of ecosystems and controls some of the services they deliver to humans, including in agriculture. However, the importance of interspecific vs the intraspecific trait variability (ITV) for classifying species according to their traits in agrosystems on a large diversity of pedoclimatic situations and cropping systems remains still open. Here, we addressed three questions: How do measured traits vary across years and seasons? Are species rankings conserved across years and season? And which traits and species are the more stable and repeatable for sown and spontaneous species? We conducted a two‐year experiment in a vineyard, and we measured four leaf and plant functional traits of 14 sown species and 43 spontaneous species that grew among sown species. Traits were measured at two key phenological stages for grapevine: budburst and flowering during two successive years with contrasted rainfall (2017 and 2018). We studied seasonal and interannual trait variations, rankings between species, and variance partitioning. The species factor explained the greatest part of trait variations across years and seasons. Sown and spontaneous species traits varied in the same way, and traits related to plant dry matter contents were the more stable across periods. Moreover, species rankings were conserved across years and seasons for all traits except plant height. Sown species showed better ranking conservation than spontaneous species overall. The trait‐based approach seems promising for the comparison of various cropping systems involving sown and spontaneous species, and may help identifying service crop species related to specific agroecosystem services. Further research is needed to bring more knowledge on trait variations under a diversity of agrosystems, and to improve theoretical frameworks that would help the design of sustainable agrosystems that provide

Potassium (K+) nutrition is of relevant interest for winegrowers because it influences grapevine growth, berry composition, as well as must and wine quality. Indeed, wine quality strongly depends on berry composition at harvest. However, K+ content of grape berries increased steadily over the last decades, in part due to climate change. Currently, the properties and qualities of many fruits are also impacted by environment. In grapevine, this disturbs berry properties resulting in unbalanced wines with poor organoleptic quality and low acidity. This requires a better understanding of the molecular basis of K+ accumulation and its control along grape berry development. This mini-review summarizes our current knowledge on K+ nutrition in relation with fruit quality in the context of a changing environment.

Among all causes of grapevine decline, Grapevine Trunk Diseases (GTDs) are major concerns for grape growers. This paper reviews knowledge and proposes hypotheses on two major GTDs, esca and Botryosphaeria dieback, and assembles a conceptual model. The objective was to collect information into a sequence, from grapevine nursery propagation processes, through foliar symptom expression, to plant death in mature vineyards. Pathogen infection and colonization steps in woody vine tissues, and the hypotheses that have been formulated to explain the outburst of foliar symptoms, are reported and discussed. Factors that could aggravate or repress GTD symptoms and incidence expansion are also addressed. Vine physiology and pathology together could expand understanding of these diseases. Knowledge and hypotheses that need validation are summarized, and a conceptual model is proposed to explain the occurrence of symptoms and the influencing factors. The model could be useful to cope with the complexity of GTDs, and as a starting point for research to unravel knowledge gaps and suggest new disease management strategies.

Après avoir annoncé la disparition des droits de plantation à la fin de l'OCM-vin 2008, la Commission européenne fait marche arrière : les droits seront sauvés sous l'OCM-vin 2013, mais sous la forme d'autorisations de plantations à partir du 01/01/2016, ce que n'est pas la même chose. Ces droits, présents en France depuis 1936, régulent le potentiel de production viticole, car cette dernière est bien particulière en raison de la nature pérenne de la vigne. En effet, des conditions climatiques trop favorables peuvent engendrer de la surproduction qui impactera le marché du vin, car la demande est incapable de l'absorber ; celle-ci est en baisse en France depuis les années soixante. Notre thèse vise à comprendre les changements qu'amène le passage des droits aux autorisations pour mesurer l'impact économique. Dans cette analyse économique nous sommes guidées par deux fils conducteurs, qui sont à la base de nos hypothèses de recherche : l'évolution de la stratégie de croissance des exploitations viticoles et le devenir de la régulation du potentiel de production sous la nouvelle OCM. La particularité de notre travail est la prise en compte de la réglementation foncière qui régule l'accès au foncier viticole et crée des distorsions sur l'application des OCM-vins. Or ce règlement foncier évolue lui aussi avec l'introduction de la LAAAF et son application simultanée le 01/01/2016. Ainsi nous étudions l'impact économique de cette double évolution en prenant compte la dynamique du droit et son effectivité.

The trait‐based approach can address questions in order to understand how the functioning of organisms scales up to that of ecosystems and controls some of the services they deliver to humans, including in agriculture. However, the importance of interspecific vs the intraspecific trait variability (ITV) for classifying species according to their traits in agrosystems on a large diversity of pedoclimatic situations and cropping systems remains still open. Here, we addressed three questions: How do measured traits vary across years and seasons? Are species rankings conserved across years and season? And which traits and species are the more stable and repeatable for sown and spontaneous species? We conducted a two‐year experiment in a vineyard, and we measured four leaf and plant functional traits of 14 sown species and 43 spontaneous species that grew among sown species. Traits were measured at two key phenological stages for grapevine: budburst and flowering during two successive years with contrasted rainfall (2017 and 2018). We studied seasonal and interannual trait variations, rankings between species, and variance partitioning. The species factor explained the greatest part of trait variations across years and seasons. Sown and spontaneous species traits varied in the same way, and traits related to plant dry matter contents were the more stable across periods. Moreover, species rankings were conserved across years and seasons for all traits except plant height. Sown species showed better ranking conservation than spontaneous species overall. The trait‐based approach seems promising for the comparison of various cropping systems involving sown and spontaneous species, and may help identifying service crop species related to specific agroecosystem services. Further research is needed to bring more knowledge on trait variations under a diversity of agrosystems, and to improve theoretical frameworks that would help the design of sustainable agrosystems that provide

Potassium (K+) nutrition is of relevant interest for winegrowers because it influences grapevine growth, berry composition, as well as must and wine quality. Indeed, wine quality strongly depends on berry composition at harvest. However, K+ content of grape berries increased steadily over the last decades, in part due to climate change. Currently, the properties and qualities of many fruits are also impacted by environment. In grapevine, this disturbs berry properties resulting in unbalanced wines with poor organoleptic quality and low acidity. This requires a better understanding of the molecular basis of K+ accumulation and its control along grape berry development. This mini-review summarizes our current knowledge on K+ nutrition in relation with fruit quality in the context of a changing environment.

Grenache Noir and Syrah are two of the grapevine (Vitis vinifera L.) cultivars used to a great extent worldwide. They have very different leaf morphologies from an ampelographic (botanical) point of view. This might also be related to differences in the anatomy and micro-morphology of their leaves. The goal of the present work was to compare these cultivars' leaf anatomy and morphology. Adult leaves from both cultivars were characterised using a range of microscopy techniques. Grenache Noir had a significantly smaller leaf surface area, but a significantly thicker leaf blade, than Syrah. It also had significantly larger stomata and a larger stomatal index than Syrah. The distribution of mesophyll tissues was similar in both cultivars, but the upper epidermis was significantly thicker in Grenache Noir, and the palisade parenchyma cells were longer in Syrah. The mesophyll tissues of both cultivars contained abundant idioblasts carrying crystals of calcium oxalate and mucilage. This work reveals quantitative and qualitative differences in the anatomy and morphology of mature Grenache Noir and Syrah leaves. Further work is needed to determine how these anatomical and morphological differences may be connected with different responses at the functional level.

Grapevine downy mildew (GDM) is a severe disease of grapevines. Because of the lack of reliable information about the dates of GDM symptom onset, many vine growers begin fungicide treatments early in the season. We evaluate the extent to which such preventive treatments are justified. Observational data for 266 untreated sites for the years between 2010 and 2017 were used to estimate the timing of GDM onset on vines and bunches of grapes in South West France (Bordeaux region) through survival analyses. The onset of GDM was not apparent on vines and bunches before early to mid-May, and the rate of GDM symptom appearance was highly variable across years. Depending on the year, 50% of the plots displayed symptoms between mid-May and late June for vines. For several years, our statistical analysis revealed that the proportion of plots with no symptoms was high in early August on vines (27.5 and 43.7% in 2013 and 2016) and on bunches (between 23 and 79% in 2011, 2013, and 2016). We found a significant effect of the amount of rainfall in spring on the date of symptom appearance. These results indicate that preventive fungicide application is unjustified in many vineyards, and that regional disease surveys should be used to adjust fungicide treatment dates according to local characteristics, in particular according to rainfall conditions in spring.

How do invasive pests affect interactions between members of pre-existing agrosystems? The invasive pest Drosophila suzukii is suspected to be involved in the aetiology of sour rot, a grapevine disease that otherwise develops following Drosophila melanogaster infestation of wounded berries. We combined field observations with laboratory assays to disentangle the relative roles of both Drosophila in disease development. We observed the emergence of numerous D. suzukii, but no D. melanogaster flies, from bunches that started showing mild sour rot symptoms days after field collection. However, bunches that already showed severe rot symptoms in the field mostly contained D. melanogaster. In the laboratory, oviposition by D. suzukii triggered sour rot development. An independent assay showed the disease increased grape attractiveness to ovipositing D. melanogaster females. Our results suggest that in invaded vineyards, D. suzukii facilitates D. melanogaster infestation and, consequently, favours sour rot outbreaks. Rather than competing with close species, the invader subsequently permits their reproduction in otherwise non-accessible resources and may cause more frequent, or more extensive, disease outbreaks.

How do invasive pests affect interactions between members of pre-existing agrosystems? The invasive pest Drosophila suzukii is suspected to be involved in the aetiology of sour rot, a grapevine disease that otherwise develops following Drosophila melanogaster infestation of wounded berries. We combined field observations with laboratory assays to disentangle the relative roles of both Drosophila in disease development. We observed the emergence of numerous D. suzukii, but no D. melanogaster flies, from bunches that started showing mild sour rot symptoms days after field collection. However, bunches that already showed severe rot symptoms in the field mostly contained D. melanogaster. In the laboratory, oviposition by D. suzukii triggered sour rot development. An independent assay showed the disease increased grape attractiveness to ovipositing D. melanogaster females. Our results suggest that in invaded vineyards, D. suzukii facilitates D. melanogaster infestation and, consequently, favours sour rot outbreaks. Rather than competing with close species, the invader subsequently permits their reproduction in otherwise non-accessible resources and may cause more frequent, or more extensive, disease outbreaks.

[Aims] To investigate the relationships between the anthocyanin content of Vitis vinifera L. cvs. Tempranillo and Graciano grapes, determined in the vineyard and in the winery by a non-invasive fluorescence sensor, and the final wine color and phenolic traits., [Methods and results] Grape anthocyanin and phenol measurements were conducted with a hand-held, non-destructive fluorescence-based proximal sensor, in the vineyard (on clusters hanging on the vine) and at the winery (on harvested clusters in boxes) in two seasons. The anthocyanin fluorescence indices, ANTHRG and FERARI, were found to significantly correlate with the wine color density (R2 ranged from 0.51 to 0.82) and total phenol index (R2 ranged from 0.44 to 0.87), regardless that the measurements were made in the vineyard or in the winery. Similarly, the CIELAB parameters defining lightness (L*), hue angle (h*) and coordinate b* (yellow-blue component of the wine tonality) also showed significant relationships (R2 ranged from 0.55 to 0.74) with ANTHRG and FERARI indices in very young wines., [Conclusion] This preliminary study showed that satisfactory estimation of the final wine color and phenolic characteristics can be obtained from fast, non-destructive measurements in grapes, using a fluorescence-based sensor, either in the vineyard or in the winery., [Significance and impact of the study] This is the first work showing the capabilities of the chlorophyll fluorescence of grapes to estimate the final wine color and phenolic traits. This information could help the wine industry make more informed decisions regarding selective harvest and winemaking in a fast and cost-effective way. © Vigne et Vin Publications Internationales (Bordeaux, France).

[EN] The use of consensus chloroplast microsatellites primers for dicotyledonous chloroplast genomes revealed the existence of intra and interspecific length variation within the genus Vitis. Three chloroplast microsatellite loci were found to be polymorphic in samples of Vitis vinifera, Vitis berlandieri, Vitis riparia, and Vitis rupestris out of a total of 10 consensus primer pairs tested. These polymorphisms were always due to a variable number of mononucleotide residues within A and (or) T stretches in the amplified regions. Chloroplast microsatellite polymorphisms were used to demonstrate the maternal inheritance of chloroplast in V. vinifera and to characterise the chloroplast haplotypes present in wine grape cultivars of this species grown in Spain and Greece. The different distribution of haplotype frequencies in the two ends of the Mediterranean growth area suggests the existence of independent domestication events for grapevine.Key words: Vitis, grapevine, chloroplast microsatellites, chloroplast haplotypes, chloroplast inheritance, grapevine domestication., [ES] L’emploi d’amorces consensus pour l’ADN chloroplastique chez les dicotylédones révèle la présence de variabilité intra- et interspécifique au sein du genre Vitis. Trois locus microsatellites chloroplastiques se sont avérés polymorphes chez le Vitis vinifera, le Vitis barlandieri, le Vitis riparia et le Vitis rupestris parmi un ensemble de dix amorces consensus employées. Ces polymorphismes étaient presque toujours dus à un nombre variable de nucléotides A ou T au sein d’une suite mononucléotidique dans la région amplifiée. Les polymorphismes de l’ADN chloroplastique ont été employés pour démontrer l’hérédité maternelle du chloroplaste chez le V. vinifera et pour caractériser les haplotypes chloroplastiques présents chez les cépages à vin cultivés en Espagne et en Grèce. La distribution différente quant à la fréquence des haplotypes aux deux extrémités de la zone méditerranéenne de culture suggère des événements indé- pendants de domestication de la vigne.

Des études récentes ont identifié dans l'enherbement du vignoble une réponse possible aux objectifs de durabilité et de qualité que se doit de s'approprier la viticulture de demain. Pourtant, la concurrence hydrique qu'il induit est un frein à son adoption dans les vignobles méditerranéens. Ce travail vise à évaluer une approche à réservoir pour modéliser le bilan hydrique de l'association vigne-culture intercalaire. Il est une première étape vers l'obtention d'un outil d'évaluation de ces pratiques. Le choix s'est porté sur STICS qui a l'avantage d'avoir déjà été paramétré pour une vigne et de proposer un formalisme relativement élaboré de modèle de sol à réservoirs. Ce travail de modélisation s'appuie sur 4 campagnes de mesures réalisées sur des parcelles viticoles du Languedoc. Sur ces parcelles, les teneurs en eau du sol et la densité apparente ont été suivies à différentes profondeurs. D'autres éléments ont été mesurés qui permettent de paramétrer le modèle. L'association vigne-enherbement, présente sur une seule de ces situations, a fait l'objet d'une étude plus complète avec une observation de son système racinaire et des flux hydriques. Outre ces données recueillies, le paramétrage du modèle a fait appel à un précédent paramétrage réalisé sur un vignoble de Côtes-du-Rhône et à des références trouvées dans la bibliographie. L'évaluation du modèle sur la réserve hydrique du sol pour une vigne en sol nu en conditions méditerranéennes s'est avérée globalement satisfaisante. Les formalismes introduits dans STICS permettent une amélioration sensible de la qualité de la simulation par rapport à un modèle plus simple comme celui de Riou et al (1994), notamment pour l'évaporation et le ruissellement. L'étude de l'association culturale semble justifier d'essayer de modéliser l'association culturale en compartimentant le sol en deux réservoirs étanches, un pour chaque culture. L'évaluation de cette hypothèse montre cependant que le réservoir dédié à la vigne ne peut pa

Des études récentes ont identifié dans l'enherbement du vignoble une réponse possible aux objectifs de durabilité et de qualité que se doit de s'approprier la viticulture de demain. Pourtant, la concurrence hydrique qu'il induit est un frein à son adoption dans les vignobles méditerranéens. Ce travail vise à évaluer une approche à réservoir pour modéliser le bilan hydrique de l'association vigne-culture intercalaire. Il est une première étape vers l'obtention d'un outil d'évaluation de ces pratiques. Le choix s'est porté sur STICS qui a l'avantage d'avoir déjà été paramétré pour une vigne et de proposer un formalisme relativement élaboré de modèle de sol à réservoirs. Ce travail de modélisation s'appuie sur 4 campagnes de mesures réalisées sur des parcelles viticoles du Languedoc. Sur ces parcelles, les teneurs en eau du sol et la densité apparente ont été suivies à différentes profondeurs. D'autres éléments ont été mesurés qui permettent de paramétrer le modèle. L'association vigne-enherbement, présente sur une seule de ces situations, a fait l'objet d'une étude plus complète avec une observation de son système racinaire et des flux hydriques. Outre ces données recueillies, le paramétrage du modèle a fait appel à un précédent paramétrage réalisé sur un vignoble de Côtes-du-Rhône et à des références trouvées dans la bibliographie. L'évaluation du modèle sur la réserve hydrique du sol pour une vigne en sol nu en conditions méditerranéennes s'est avérée globalement satisfaisante. Les formalismes introduits dans STICS permettent une amélioration sensible de la qualité de la simulation par rapport à un modèle plus simple comme celui de Riou et al (1994), notamment pour l'évaporation et le ruissellement. L'étude de l'association culturale semble justifier d'essayer de modéliser l'association culturale en compartimentant le sol en deux réservoirs étanches, un pour chaque culture. L'évaluation de cette hypothèse montre cependant que le réservoir dédié à la vigne ne peut pa

Le gel hivernal au Québec est l'un de facteurs déterminants qui influence la survie et le rendement de la vigne. La connaissance du mode d'action de ce facteur climatique présente un grand intérêt pour les agronomes et les praticiens qui se préoccupent de la protection de la vigne. Plusieurs types de protection de la vigne contre le gel hivernai i.e. [hivernal] sont utilisés (buttage surtout et enfeuillage) ou expérimentés (la toile de géotextile et le cône de polystyrène). Afin d'évaluer la qualité de différents types de protection du Seyval nous avons mené une recherche au vignoble Sous les Charmilles à Rock Forest de décembre 1997 à octobre 1998. Des données de températures au sol, sous différents abris (butte de terre, butte de feuilles, neige raportée et neige naturelle) et de l'air ambiant sont enregistrées à l'aide de thermocouples reliés à un système automatique d'acquisition de données.

[ES] Una política adecuada en recursos genéticos requiere la correcta identificación de las accesiones conservadas en los Bancos de Germoplasma. En la vid, la estimación del número real de variedades disponibles se torna difícil por la existencia de numerosas denominaciones que corresponden a sinonimias y homonimias. La caracterización mediante marcadores moleculares de cuarenta accesiones de vid, correspondientes a variedades minoritarias existentes en La Rioja y a variedades de otras procedencias postuladas como sinonimias de las variedades anteriores, constituyó el objetivo principal de esta Tesis. Las variedades que se estudiaron, pertenecientes a las colecciones de los Bancos de Germoplasma de Logroño (La Rioja) y El Encín (Madrid), integraron cinco grupos de estudio., [FR] Une politique adéquate en ressources génétiques exige la bonne identification des accesions conservées dans les Banques de Germoplasme. Dans la vigne, l'estimation du nombre réel de variétés disponibles se rend difficile a cause de l'existence de nombreuses appelations qui correspondent a des synonymies et des homonymies. La caractérisation grace aux marqueurs moléculaires de quarante accessions de vigne, correspondantes a des variétés minoritaires existentes dans La Rioja et a des varietés d'autres origines postulées comme synonymies des variétés précédentes, ont constitué le but principal de cette These. Les variétés qui ont été étudiées, appartenant aux collections des Banques de Germoplasme de Logroño (La Rioja) et El Encín (Madrid), ont compris cinq groupes d'étude., [EN] A policy for genetic resources requires the correct identification of accessions preserved in the Germplasm Banks. In grapevines, estimation of the actual numbers of varieties available becomes difficult because of the existence of numerous denominations corresponding to synonymies and homonymies. Characterization by means of molecular markers of forty vme access1ons corresponding to thinly scattered varieties existing in La Rioja and to varieties of other origins postulated as synonymies of the former varieties, constitute the principal objective of this Thesis. The varieties studied, belonging to the collections of the Germplasm Banks of Logroño (La Rioja) and El Encín (Madrid), formed five study groups.

Les premiers résultats de production de la vigne de table à la Guadeloupe sont encourageants. Les essais variétaux ont mis en évidence les qualités du Muscat d'Alexandrie

Les premiers résultats de production de la vigne de table à la Guadeloupe sont encourageants. Les essais variétaux ont mis en évidence les qualités du Muscat d'Alexandrie

Synthèse trilingue (français, anglais, espagnol) des communications présentées lors de la réunion annuelle sur les vergers tropicaux. Une place importante est accordée aux agrumes et aux mangues. Accent mis aussi bien sur l'agroéconomie, les technologies post-récolte et les transformations, la défense des cultures, l'écophysiologie, la génétique et les biotechnologies..

Synthèse trilingue (français, anglais, espagnol) des communications présentées lors de la réunion annuelle sur les vergers tropicaux. Une place importante est accordée aux agrumes et aux mangues. Accent mis aussi bien sur l'agroéconomie, les technologies post-récolte et les transformations, la défense des cultures, l'écophysiologie, la génétique et les biotechnologies..

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Référence bibliographique : Leroy-Crèvecoeur, 431, Appartient à l’ensemble documentaire : FranceJp0, Diplôme

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Référence bibliographique : Leroy-Crèvecoeur, 188, Appartient à l’ensemble documentaire : FranceJp0, Couverture

Référence bibliographique : Leroy-Crèvecoeur, 171, Appartient à l’ensemble documentaire : FranceJp0, Couverture

Appartient à l’ensemble documentaire : GTextes1, Contient une table des matières, Avec mode texte

Appartient à l’ensemble documentaire : GTextes1

Appartient à l’ensemble documentaire : GTextes1, Contient une table des matières, Avec mode texte

Appartient à l’ensemble documentaire : GTextes1, Contient une table des matières, Avec mode texte

Appartient à l’ensemble documentaire : GTextes1, Contient une table des matières, Avec mode texte

Appartient à l’ensemble documentaire : GTextes1, Avec mode texte