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IVES 9 IVES Conference Series 9 Open-GPB 9 Open-GPB-2024 9 Flash - Biotic interactions 9 Mining microbiome data to identify antagonists of grapevine downy mildew (Plasmopara viticola)

Mining microbiome data to identify antagonists of grapevine downy mildew (Plasmopara viticola)

Abstract

Vineyards are home to a myriad of microorganisms that interact with each other and with the vines. Some microorganisms are plant pathogens, such as the oomycete Plasmopara viticola, causing grapevine downy mildew. Others have a positive effect on vine health, such as disease biocontrol agents. These beneficial plant-microbe and microbe-microbe interactions have gained more attention in recent years because they could represent an alternative to the use of fungicides in viticulture. The aim of the present study is to identify bacterial and fungal taxa naturally present in vineyard soil and grapevine leaves and significantly more abundant in plots with low susceptibility to downy mildew (DM), susceptibility being defined by the intensity and frequency of DM symptoms over several years. Seven pairs of vineyard plots with contrasting susceptibility to DM were selected on the basis of a long-term epidemiological survey conducted in the Bordeaux region by the IFV. In each plot, we sampled young leaves (at phenological stage of 2-3 spreading leaves) and surface soil (top 5 cm) before the first fungicide treatments of the growing season. We used metabarcoding approaches to explore the entire microbial community of the samples. Up to 1974 and 769 taxonomic units of bacteria and fungi respectively were identified. Using differential abundance analyses, we could identify taxa that were significantly more abundant in plots of vines with low susceptibility to DM. As perspectives, the antagonistic activity of these taxa will be studied experimentally to develop microbial biocontrol of downy mildew and move viticulture towards pesticide-free viticulture.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Paola Fournier1,2,3*, Lucile Pellan1, Aarti Jaswa1,4, Jessica Vallance1, Emilie Chancerel2, Olivier Bonnard2, Marc Raynal5, Christian Debord5, Simon Labarthe2, Laurent Deliere1, François Delmotte1, Patrice This3, Corinne Vacher2

1INRAE, Bordeaux Sciences Agro, ISVV, SAVE, 33140 Villenave-d’Ornon, France
2INRAE, Univ Bordeaux, BioGeCo, 33610 Cestas, France
3INRAE, CIRAD, Univ Montpellier, Institut AGRO, AGAP institut, 34398 Montpellier, France
4Univ Bordeaux, UMR oenologie, INRAE, Bx INP, Bordeaux Sciences Agro, ISVV, 33882 Villenave d’Ornon ,France
5IFV, 33290 Blanquefort, France

Contact the author*

Keywords

Plasmopara viticola, phyllosphere, pest management, sustainable viticulture, grape-associated microorganisms

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

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