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Jean-michel Mérillon - One of the best experts on this subject based on the ideXlab platform.
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Pinus pinaster Knot: A Source of Polyphenols against Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Marie-france Corio-costet, Tristan Richard, Stéphanie Cluzet, Antonio Palos Pinto, Marie-cécile Dufour, Jean-michel MérillonAbstract:Pine knot extract from Pinus pinaster byproducts was characterized by UHPLC-DAD-MS and NMR. Fourteen polyphenols divided into four classes were identified as follows: lignans (nortrachelogenin, pinoresinol, matairesinol, isolariciresinol, secoisolariciresinol), flavonoids (pinocembrin, pinobanksin, dihydrokaempferol, taxifolin), stilbenes (pinosylvin, pinosylvin monomethyl ether, pterostilbene), and phenolic acids (caffeic acid, ferulic acid). The antifungal potential of pine knot extract, as well as the main compounds, was tested in vitro against Plasmopara viticola. The ethanolic extract showed a strong antimildew activity. In addition, pinosylvins and pinocembrin demonstrated significant inhibition of zoospore mobility and mildew development. These findings strongly suggest that pine knot is a potential biomass that could be used as a natural antifungal product.
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Stilbenes from Vitis vinifera L. Waste: A Sustainable Tool for Controlling Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-e-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
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Stilbenes from Vitis vinifera L. Waste: A sustainable tool for controlling Plasmopara viticola
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-ε-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
Marie-france Corio-costet - One of the best experts on this subject based on the ideXlab platform.
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Pinus pinaster Knot: A Source of Polyphenols against Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Marie-france Corio-costet, Tristan Richard, Stéphanie Cluzet, Antonio Palos Pinto, Marie-cécile Dufour, Jean-michel MérillonAbstract:Pine knot extract from Pinus pinaster byproducts was characterized by UHPLC-DAD-MS and NMR. Fourteen polyphenols divided into four classes were identified as follows: lignans (nortrachelogenin, pinoresinol, matairesinol, isolariciresinol, secoisolariciresinol), flavonoids (pinocembrin, pinobanksin, dihydrokaempferol, taxifolin), stilbenes (pinosylvin, pinosylvin monomethyl ether, pterostilbene), and phenolic acids (caffeic acid, ferulic acid). The antifungal potential of pine knot extract, as well as the main compounds, was tested in vitro against Plasmopara viticola. The ethanolic extract showed a strong antimildew activity. In addition, pinosylvins and pinocembrin demonstrated significant inhibition of zoospore mobility and mildew development. These findings strongly suggest that pine knot is a potential biomass that could be used as a natural antifungal product.
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Stilbenes from Vitis vinifera L. Waste: A Sustainable Tool for Controlling Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-e-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
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Stilbenes from Vitis vinifera L. Waste: A sustainable tool for controlling Plasmopara viticola
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-ε-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
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Fungicide resistance in Plasmopara viticola in France and anti resistance measures
2011Co-Authors: Marie-france Corio-costetAbstract:Grapevine downy mildew (Plasmopara viticola) is a major disease causing widespread destruction in vineyards throughout the world. It was introduced into France in 1878, in the wake of the Phylloxera epidemic, and was discovered by Planchon in vineyards in Coutras (Bordeaux region). This chapter describes the resistance of this pathogen to some fungicides in France, including phenylamides, mitochondrial inhibitors (quinone outside inhibitors and quinone inside inhibitors), cell wall inhibitors (carboxylic acid amide fungicides), cymoxanil, and multi-site and miscellaneous fungicides; and presents several anti-resistance measures.
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Diversity and fitness of Plasmopara viticola isolates resistant to QoI fungicides
European Journal of Plant Pathology, 2011Co-Authors: Marie-france Corio-costet, Marie-cécile Dufour, Jérémy Cigna, Pierre Abadie, Wei-jen ChenAbstract:The effectiveness of Quinone outside Inhibitor (QoI) fungicides against grape downy mildew in European vineyards has significantly decreased in the last decade. One nucleotide polymorphism, G143A in the cytochrome b gene of Plasmopara viticola, is involved in resistance to QoIs. Previous genetic examination on the mitochondrial genomes showed four major haplotypes (IR, IS, IIR, IIS) coexisting in European vineyards. A resistant allele (G143A) was present in IR and IIR haplotypes. The purpose of the present study was to estimate the diversity of the different mitochondrial haplotypes and their distribution in QoI-resistant populations before evaluating the potential cost of the resistant mutation G143A in P. viticola population. From 2000 to 2004, the frequencies of resistant isolates ranged from 0% to 23.25% with an average of 4.64 % among the populations examined. To evaluate the fitness of sensitive and resistant isolates, a comparison of different biological parameters including latent period, spore production and infection frequency was performed, enabling a fitness index (FI) to be determined. Resistant isolates exhibited greater infection frequency than sensitive isolates, whereas no significant difference was found in sporulation ability and latent period between sensitive and resistant isolates. To further investigate competitiveness among isolates, an assay including two resistant isolates in different proportion with a sensitive isolate was conducted on eight asexual growing cycles in the absence of a QoI fungicide. The competitiveness of resistant isolates varied according to their fitness parameters, suggesting that there is no noticeable cost of QoI resistance in controlled conditions in Plasmopara viticola.
Julien Gabaston - One of the best experts on this subject based on the ideXlab platform.
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Pinus pinaster Knot: A Source of Polyphenols against Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Marie-france Corio-costet, Tristan Richard, Stéphanie Cluzet, Antonio Palos Pinto, Marie-cécile Dufour, Jean-michel MérillonAbstract:Pine knot extract from Pinus pinaster byproducts was characterized by UHPLC-DAD-MS and NMR. Fourteen polyphenols divided into four classes were identified as follows: lignans (nortrachelogenin, pinoresinol, matairesinol, isolariciresinol, secoisolariciresinol), flavonoids (pinocembrin, pinobanksin, dihydrokaempferol, taxifolin), stilbenes (pinosylvin, pinosylvin monomethyl ether, pterostilbene), and phenolic acids (caffeic acid, ferulic acid). The antifungal potential of pine knot extract, as well as the main compounds, was tested in vitro against Plasmopara viticola. The ethanolic extract showed a strong antimildew activity. In addition, pinosylvins and pinocembrin demonstrated significant inhibition of zoospore mobility and mildew development. These findings strongly suggest that pine knot is a potential biomass that could be used as a natural antifungal product.
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Stilbenes from Vitis vinifera L. Waste: A Sustainable Tool for Controlling Plasmopara viticola.
Journal of agricultural and food chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-e-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
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Stilbenes from Vitis vinifera L. Waste: A sustainable tool for controlling Plasmopara viticola
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Julien Gabaston, Emma Cantos-villar, Benoit Biais, Pierre Waffo-teguo, Elodie Renouf, Marie-france Corio-costet, Tristan Richard, Jean-michel MérillonAbstract:Stilbene-enriched extracts from Vitis vinifera waste (cane, wood, and root) were characterized by UHPLC-MS. Eleven stilbenes were identified and quantified as follows: ampelopsin A, (E)-piceatannol, pallidol, (E)-resveratrol, hopeaphenol, isohopeaphenol, (E)-ε-viniferin, (E)-miyabenol C, (E)-ω-viniferin, r2-viniferin, and r-viniferin. The fungicide concentration inhibiting 50% of growth of Plasmopara viticola sporulation (IC50) was determined for the extracts and also for the main compounds isolated. r-Viniferin followed by hopeaphenol and r2-viniferin showed low IC50 and thus high efficacy against Plasmopara viticola. Regarding stilbene extracts, wood extract followed by root extract showed the highest antifungal activities. These data suggest that stilbene complex mixtures from Vitis vinifera waste could be used as a cheap source of bioactive stilbenes for the development of natural fungicides.
S. Boso - One of the best experts on this subject based on the ideXlab platform.
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Susceptibility to downy mildew (Plasmopara viticola) of different Vitis varieties
Crop Protection, 2014Co-Authors: S. Boso, J.l. Santiago, Virginia Alonso-villaverde, P. Gago, M.c. MartínezAbstract:Abstract The susceptibility of different varieties of Vitis vinifera and other Vitis species to downy mildew (caused by Plasmopara viticola ) in field, greenhouse and laboratory tests was compared over a period of three years. Different degrees of susceptibility were detected. The most susceptible V. vinifera varieties were ‘Treixadura’ and ‘Albarino; ‘Cabernet Sauvignon’, ‘Mencia’ and ‘Chasselas Dore’ were the least susceptible. The non- vinifera varieties showed no symptoms of downy mildew in the field. Surprisingly, in laboratory and greenhouse tests, the rootstock 110-R was much more susceptible to infection than S04. No relationship was seen between susceptibility and berry colour, or the time of sprouting or fruit ripening. Neither was any correlation seen between susceptibility and the condition of being a traditional or introduced variety. Better knowledge of the susceptibility to downy mildew of different varieties would allow for growers and breeders to select those that are more resistant.
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Quantification of Stilbenes in Vitis Genotypes with Different Levels of Resistance to Plasmopara viticola Infection
American Journal of Enology and Viticulture, 2012Co-Authors: S. Boso, Virginia Alonso-villaverde, María-carmen Martínez, Hanns-heinz KassemeyerAbstract:Stilbenic phytoalexins have been associated with disease resistance. In Vitis spp., stilbene synthesis can be induced by UV irradiation, treatment with a variety of substance extracts, and inoculation with Botrytis cinerea or Plasmopara viticola . The aim of the present work was to examine the relationship between stilbene production and the level of resistance of different Vitis genotypes to P. viticola . The ability of different grapevine genotypes ( Vitis vinifera L. cvs. Tempranillo, Touriga Nacional, Pinot noir, and Cabernet Sauvignon and Vitis riparia cv. Gloire de Montpellier) to resist Plasmopara viticola infection was assessed via their potential to accumulate toxic stilbenic phytoalexins. Leaf discs taken from plants belonging to these genotypes were inoculated with P. viticola sporangia and disease severity was determined five days later. Stilbene production was quantified in similar leaf material at 6, 24, 48, and 72 hr postinoculation. After P. viticola infection, the resistant genotype V. riparia showed high production of the phytotoxic stilbenes ɛ- and δ-viniferin, which limited the development of the pathogen and prevented it from producing spores. Indeed, this genotype was associated with the lowest sporulation values. No relationship was observed, however, between resistance and these compounds in the V. vinifera genotypes. Further study is required to define the role of stilbenic phytoalexins in resistance to P. viticola.
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The Course of Colonization of Two Different Vitis Genotypes by Plasmopara viticola Indicates Compatible and Incompatible Host-Pathogen Interactions.
Phytopathology, 2007Co-Authors: Sabine Unger, S. Boso, Claudia Büche, Hanns-heinz KassemeyerAbstract:Unger, S., Buche, C., Boso, S. and Kassemeyer, H.-H. 2007. The course of the colonization of two different Vitis genotypes by Plasmopara viticola indicates compatible and incompatible host–pathogen interactions. Phytopathology 97:780-786. The course of colonization of leaf mesophyll by the causal agent of grapevine downy mildew, Plasmopara viticola, in a susceptible and a resistant grapevine genotype was examined in order to characterize the development of the pathogen in compatible and incompatible host–pathogen interactions. Within a few hours after inoculation, the pathogen was established in the susceptible Vitis vinifera cv. Muller-Thurgau and formed primary hyphae with a first haustorium. No further development occurred in the following 10 to 18 h. The next step, in which the hyphae grew and branched to colonize the intercellular space of the host tissue, was observed 1.5 days after inoculation. After 3 days, the intercostal fields were entirely filled with mycelium and sporulation was abundant under favorable environmental conditions. The first infection steps were essentially the same in the resistant V. rupestris. However, the invasive growth of P. viticola was delayed, and further development ceased before the intercostal fields were filled with mycelium. Additional keyword: resistance.
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Resistance of eight different clones of the grape cultivar Albariño to Plasmopara viticola
Plant disease, 2004Co-Authors: S. Boso, J.l. Santiago, M.c. MartínezAbstract:Resistance to downy mildew (Plasmopara viticola) was studied in eight clones of the grape (Vitis vinifera) cultivar Albarino (confirmed as such by DNA and ampelographic analysis) growing at the Mision Biologica de Galicia, Spain. Resistance to downy mildew was quantified using an image processor. Some clones (CSIC-10 and CSIC-11) were more resistant than others to leaf infection by P. viticola. However, the susceptibility of grape clusters did not differ significantly among the clones.
Alain Pugin - One of the best experts on this subject based on the ideXlab platform.
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Changes in carbohydrate metabolism in Plasmopara viticola-infected grapevine leaves.
Molecular Plant-Microbe Interactions, 2011Co-Authors: Magdalena Gamm, Sophie Trouvelot, Marie-claire Héloir, Richard Bligny, Nathalie Vaillant-gaveau, Gérard Alcaraz, Patrick Frettinger, Christophe Clément, Alain Pugin, David WendehenneAbstract: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) activity and modifications in the starch degradation pathway, especially an increased α-amylase activity. Together with these alterations in starch metabolism, we have observed an accumulation of hexoses, an increase in invertase activity, and a reduction of photosynthesis, indicating a source-to-sink transition in infected leaf tissue. Additionally, we have measured an accumulation of the disaccharide trehalose correlated to an increased trehalase gene expression and enzyme activity. Altogether, these results highlight a dramatic alteration of carbohydrate metabolism correlated with later stages of P. viticola development in leaves.
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Stomatal deregulation in Plasmopara viticola-infected grapevine leaves
New Phytologist, 2007Co-Authors: Mathilde Allegre, Sophie Trouvelot, Xavier Daire, Marielle Adrian, Marie-claire Héloir, Laurence Mercier, Alain PuginAbstract:In grapevine, the penetration and sporulation of Plasmopara viticola occur via stomata, suggesting functional relationships between guard cells and the pathogen. This assumption was supported by our first observation that grapevine (Vitis vinifera cv. Marselan) cuttings infected by P. viticola wilted more rapidly than healthy ones when submitted to water starvation. • Here, complementary approaches measuring stomatal conductance and infrared thermographic and microscopic observations were used to investigate stomatal opening/closure in response to infection. • In infected leaves, stomata remained open in darkness and during water stress, leading to increased transpiration. This deregulation was restricted to the colonized area, was not systemic and occurred before the appearance of symptoms. Cytological observations indicated that stomatal lock-open was not related to mechanical forces resulting from the presence of the pathogen in the substomatal cavity. In contrast to healthy leaves, stomatal closure in excised infected leaves could not be induced by a water deficit or abscisic acid (ABA)treatment. However, ABA induced stomatal closure in epidermal peels from infected leaves, indicating that guard cells remained functional. • These data indicate that the oomycete deregulates guard cell functioning, causing significant water losses. This effect could be attributed to a nonsystemic compound, produced by the oomycete or by the infected plant, which inhibits stomatal closure or induces stomatal opening; or a reduction of the back-pressure exerted by surrounding epidermal cells. Both hypotheses are under investigation.