RVVS 2013

Stratégies de lutte contre le charançon rouge du palmier

La communauté scientifique internationale (source : publication FAO d’avril 2017) s’accorde sur l’importance de la combinaison des mesures de lutte en fonction des niveaux d’infestation par le charançon rouge du palmier. Plusieurs mesures de lutte sont disponibles ou envisageables : assainissement mécanique, application d’insecticides à titre préventif ou curatif, piégeage de masse et biocontrôle (lutte biologique sensu stricto). Il est à noter que plusieurs expérimentations sur le biocontrôle sont en cours.Dans la perspective d’améliorer les stratégies de lutte contre le charançon rouge du palmier, il est demandé : 1) d’identifier les stratégies de lutte (en tant que combinaison de différe…

Identification and characterization of the grapevine flagellin receptor vvfls2

International audience

Anti-Cancer Activity of Resveratrol and Derivatives Produced by Grapevine Cell Suspensions in a 14 L Stirred Bioreactor

International audience; In the present study, resveratrol and various oligomeric derivatives were obtained from a 14 L bioreactor culture of elicited grapevine cell suspensions (Vitis labrusca L.). The crude ethyl acetate stilbene extract obtained from the culture medium was fractionated by centrifugal partition chromatography (CPC) using a gradient elution method and the major stilbenes contained in the fractions were subsequently identified by using a (13)C-NMR-based dereplication procedure and further 2D NMR analyses including HSQC, HMBC, and COSY. Beside δ-viniferin (2), leachianol F (4) and G (4'), four stilbenes (resveratrol (1), ε-viniferin (5), pallidol (3) and a newly characterized…

Characterization of the role of flagellin in the innate immunity triggered by the endophytic pgpr burkholderia phytofirmans in arabidopsis and grapevine

International audience

Changes in carbohydrate metabolism in Plasmopara viticola-infected grapevine leaves.

International audience; The oomycete Plasmopara viticola is responsible for downy mildew, a severe grapevine disease. In infected grapevine leaves, we have observed an abnormal starch accumulation at the end of the dark period, suggesting modifications in starch metabolism. Therefore, several complementary approaches, including transcriptomic analyses, measurements of enzyme activities, and sugar quantification, were performed in order to investigate and to understand the effects of P. viticola infection on leaf starch and-to a larger extent-carbohydrate metabolism. Our results indicate that starch accumulation is associated with an increase in ADP-glucose pyrophosphorylase (AGPase) activit…

How Plasmopara viticola is able to alter grapevine leaf physiology

National audience

The grapevine flagellin receptor VvFLS2 differentially recognizes flagellin-derived epitopes from the endophytic growth-promoting bacterium Burkholderia phytofirmans and plant pathogenic bacteria.

International audience; The role of flagellin perception in the context of plant beneficial bacteria still remains unclear. Here, we characterized the flagellin sensing system flg22-FLAGELLIN SENSING 2 (FLS2) in grapevine, and analyzed the flagellin perception in the interaction with the endophytic plant growth-promoting rhizobacterium (PGPR) Burkholderia phytofirmans. The functionality of the grapevine FLS2 receptor, VvFLS2, was demonstrated by complementation assays in the Arabidopsis thaliana fls2 mutant, which restored flg22-induced H2O2 production and growth inhibition. Using synthetic flg22 peptides from different bacterial origins, we compared recognition specificities between VvFLS2…

Cultivar- and Wood Area-Dependent Metabolomic Fingerprints of Grapevine Infected by Botryosphaeria Dieback

International audience; Botryosphaeria dieback is one of the most significant grapevine trunk diseases that affects the sustainability of the vineyards and provokes economic losses. The causal agents, Botryosphaeriaceae species, live in and colonize the wood of the perennial organs causing wood necrosis. Diseased vines show foliar symptoms, chlorosis, or apoplexy, associated to a characteristic brown stripe under the bark. According to the susceptibility of the cultivars, specific proteins such as PR-proteins and other defense-related proteins are accumulated in the brown stripe compared with the healthy woody tissues. In this study, we enhanced the characterization of the brown stripe and …

Transcriptomic and metabolomic responses of the nodulated pea root system during rewatering

National audience; In pea (Pisum sativum), as in other legumes, nitrogen nutrition relies on two different sources: soil mineral nitrogen supply via roots and and symbiotic atmospheric N2 fixation within root nodules. However symbiotic nitrogen fixation is very sensitive to abiotic stresses, especially drought, which is becoming increasingly frequent in the current context of climate change. Although the ability of a crop to recover after a drought period can determine both its survival and its yield at harvest, little is known about the physiological and molecular mechanisms occurring during recovery. In this work, we aimed at characterizing the kinetics of growth and nitrogen acquisition …

Effect of water and heat stresses on the physiology of Ugni blanc infected by Neofusicoccum parvum

International audience; Botryosphaeria dieback is one of the most widespread and prevalent grapevine trunk diseases (GTDs) in Europe. Symptoms include necrosis of perennial organs of grapevine while external symptoms include bud necrosis, leaf discoloration and dead arms although incidence and severity vary from year to year. The causal agents of this disease are Botryosphaeriaceae species with Neofusicoccum parvum being one of the most prevalent. Their aggressiveness were reported to be influenced by environmental factors particularly temperature increasing disease severity. Thus, our study investigated the influence of heat and water stress on the grapevine / N. parvum interaction. Cuttin…

Biocontrol and biofertilizer activities of the Streptomyces anulatus S37: an endophytic actinomycete with biocontrol and plant-growth promoting activities

International audience

Bacterial rhamnolipids are novel MAMPs conferring resistance to Botrytis cinerea in grapevine

International audience; Rhamnolipids produced by the bacteria Pseudomonas aeruginosa are known as very efficient biosurfactant molecules. They are used for a wide range of industrial applications, especially in food, cosmetics and pharmaceutical formulations as well as in bioremediation of pollutants. In this paper, the role of rhamnolipids as novel molecules triggering defence responses and protection against the fungus Botrytis cinerea in grapevine is presented. The effect of rhamnolipids was assessed in grapevine using cell suspension cultures and vitro-plantlets. Ca2+ influx, mitogen-activated protein kinase activation and reactive oxygen species production form part of early signalling…

Cytotoxicity of Labruscol, a New Resveratrol Dimer Produced by Grapevine Cell Suspensions, on Human Skin Melanoma Cancer Cell Line HT-144

IF 2.861; International audience; A new resveratrol dimer (1) called labruscol, has been purified by centrifugal partition chromatography of a crude ethyl acetate stilbene extract obtained from elicited grapevine cell suspensions of Vitis labrusca L. cultured in a 14-liter stirred bioreactor. One dimensional (1D) and two dimensional (2D) nuclear magnetic resonance (NMR) analyses including ¹H, 13C, heteronuclear single-quantum correlation (HSQC), heteronuclear multiple bond correlation (HMBC), and correlation spectroscopy (COSY) as well as high-resolution electrospray ionisation mass spectrometry (HR-ESI-MS) were used to characterize this compound and to unambiguously identify it as a new st…

Principaux effets de l’arsénite de sodium sur la physiologie de la vigne

National audience; Dans le cadre du projet CASDAR V1301, l’impact d’un traitement à l’arsénite de sodium sur la physiologie de la vigne a été étudié chez le Chardonnay. Deux approches complémentaires, transcriptomique et métabolomique, ont été réalisées sur différents organes (tiges herbacées et tronc en distinguant le bois sain et la zone d’interaction bois sain / bois altéré) de ceps non traités sans symptômes foliaires (témoins), non traités avec symptômes foliaires et traités (n’exprimant donc plus les symptômes et qualifiés de « guéris »). Les échantillons ont été prélevés 6 mois après le traitement (avant vendanges). Parmi les principaux résultats, l’analyse transcriptomique montre qu…

Caractérisation du mode d’action des rhamnolipides dans la défense des plantes et l’induction d’une résistance contre des agents phytopathogènes biotrophes et nécrotrophes

National audience; Les rhamnolipides (RL) sont des glycolipides amphiphiles produits par différentes bactéries notamment du genre Pseudomonas et Burkholderia. Les RL comprennent généralement une chaîne d’acides gras couplée à un ou plusieurs rhamnoses. Il sont impliqués dans la formation de biofilms, dans la mobilité bactérienne et constituent, pour certaines bactéries, des facteurs de virulence (Vatsa et al. 2010). Nous avons montré que les RL sont perçus en tant qu’éliciteurs par les cellules de vigne et que cette reconnaissance provoque un influx de Ca2+, l’activation de plusieurs MAPK (Mitogen-Activated Protein Kinase), la production de formes actives de l’oxygène ainsi que l’expression…