Search results for "grape"
showing 10 items of 291 documents
Characterization of the aromatic potential of grape berry
2022
IntroductionProbe is a research infrastructure gathering 4 analytical platforms of INRAE and allowing multi-approach and multi-complementarity to be explored and exploited. As a proof of concept, a common study was conducted around the structure and the evolution of the skin of the grape berry and the diffusion of compounds of interest during the winemaking process.Materials and methodsIn this context, the aromatic potential on two Vitis vinifera grape varieties (Carignan and Grenache,) were studied. Berries were harvested at an average potential alcohol of 12% vol. in the vineyard of the Pech Rouge experimental unit (INRAE, Gruissan, France) and separated according to their natural heterog…
Botrytis cinerea strains infecting grapevine and tomato display contrasted repertoires of accessory chromosomes, transposons and small RNAs
2022
Botrytis cinerea stands out for having a wide host range and is qualified as generalist.Nevertheless, recent studies suggest that it actually corresponds to co-existing populationsthat show a certain level of host specialization, as described for the French populations T andG1, specialized on tomato and grapevine, respectively (Mercier et al., 2019, Env. Microbiol.21, 4808–21; Mercier et al., 2021 Phytopathology, 111,2355-66).What are the molecular determinants responsible for such host-specialization? PreviousIllumina sequencing data revealed genes under positive selection encoding cellulases,pectinases and enzymes involved in the oxidative stress response suggesting that theseactivities m…
Impacts of climate change on the performance of an insect pest and associated consequences for tritrophic interactions
2019
Global warming poses a major challenge to living organisms, particularly for ectothermic animals like insects, whose physiology and behaviour are closely related with direct thermal surroundings. This thesis aims at experimentally investigating the impacts of climate change on the overall performance of a major grapevine pest, the European grapevine moth (Lobesia botrana), and the associated consequences for interactions involving this phytophagous insect and adjacent trophic levels, more specifically natural enemies (parasitoids). The experiments conducted focus on three facets of climate change: an increase in mean temperature, an alteration of daily thermal range, and the occurrence of h…
Biodiversité fongique du raisin au vin : impact de l'activité anthropique
2016
The effects of different anthropogenic activities (vineyard, winery) on fungal populations from grape to wine were studied. To characterize these effects, it was necessary to access to the overall diversity of populations (pyrosequencing and spectroscopy FT-IR) but also to intra-specific diversity (FT-IR). Spectroscopy FT-IR has been validated for their ability to characterize the global population and to discriminate the strains for three species of non-Saccharomyces yeasts (NS). For the first time, it is shown that the grape berry is a limited source for NS yeasts while the winery seems to be a significant source; the air is an important vector for dissemination of these yeasts. In additi…
Le goût moisi-terreux du vin : contribution à la caractérisation cinétique et métabolique des moisissures associées à ce défaut organoleptique
2011
Some microorganisms that co-exist on the grapevine may have beneficial effects on the quality of wine whereas others may be at the origin of organoleptic deviations. In the last decade, several mouldy or earthy odors have been highlighted in various wine regions from France. (-)-geosmin was found to be the major compound responsible for this deviation, along with Botrytis cinerea and fungi belonging to the genus Penicillium, since they were frequently isolated from “earthy-musty” odor grapes. The extent of damage on the quality of wines, motivated our study on the caracterisation of grape rot fungi. First of all, the microflora of grapes from Burgundy vineyards was identified (morphological…
Impact of biostimulants on the resistance induction level of grapevine to downy mildew by elicitors
2018
The protection of vineyards against cryptogamic diseases such as downy mildew is mainly ensured by synthetic fungicides, which cause serious environmental and health problems. The induction of resistance by elicitors could allow to reduce their use. However, even if their efficacy is demonstrated in greenhouse conditions, it remains quite variable in field conditions. Indeed, the efficacy of an elicitor depends on the plant’s ability to respond, or more generally, on the latter’s physiological status. In this context, part of the FUI project IRIS+, the aim of this present work is to evaluate whether biostimulants, through their effect on the plant’s physiology, would be able to increase the…
Does leaf position influence induced resistance to grape downy mildew?
2013
National audience; We observed that protection against grape downy mildew achieved by resistance inducers was higher in the adult leaf than in the younger, not fully expanded leaf. Using sulfated laminarin as inducer, this difference of efficacy could be correlated to stronger defense reactions (i. e. H2O2, defense gene expression) in adult leaf as compared to the younger one. These findings should be taken into account in disease control strategies involving induced resistance.
Grape cultivar affects larval and female fitness of the European grapevine moth, Lobesia botrana (Lepidoptera: Tortricidae)
2005
8 pages; International audience
Impact of stresses associated to climate changes on natural and induced grapevine resistance to pathogens
2013
National audience; France is a worldwide leader in grape production and has to face global changes including climate evolution and transitions towards sustainable systems of production. One major problem in viticulture is indeed the high susceptibility of most of the grown cultivars to cryptogamic diseases, such as downy mildew (Plasmopara viticola). Maintaining a satisfactory health status of grapevine currently requires numerous fungicide treatments. However, in an objective of sustainable viticulture, there is increasing societal request, winegrower awareness, and political incitation to reduce this use of pesticides. For these reasons, alternative strategies of protection are currently …
Transcriptomes of compatible and non-compatible gray mold/grapevine interactions compared in search of resistance factors
2012
National audience; Gray mold (Botrytis cinerea) causes significant annual yield and quality losses to viticulture. Comparison of transcriptomes of compatible and non-compatible interaction with Vitis vinifera cv Marselan – on harvesting stage berries or véraison stage berries, respectively – suggest the jasmonic acid pathway is activated in the former, while the salicylic acid pathway is more pronounced in the latter. In addition, in the non-compatible case, reactive oxygen species accumulation seems to be both early and strong, and some genes involved in cell-wall reinforcement are up-regulated.