terclim by ICS banner
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.

Download the abstract

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

Related articles…

Effects of a new vacuum evaporation method on chemical and sensory properties of must and wine

A new process for vacuum evaporation was developed where evaporation takes place near the inner surface of a vortex produced by a rotor submerged in the liquid. Contrary to the state of the art the Vortex rotor process does not need a vacuum vessel but the rotating liquid creates a geometrically stable low pressure void surrounded by a vortex stabilized by the equilibrium between centrifugal forces and the pressure difference. First tests with water and sugar solutions at concentrations similar to grape must were conducted to verify the theoretical predictions, test the performance under different conditions and study the effect of various process parameters (Rösti et al 2015).

Read More

Impact of oenological tannins on microvinifications affected by downy mildew

AIM: Vine diseases are still responsible for economic losses. Previous study in our laboratory, have shown effects of oenological tannins against Botrytis cinerea1,2. According to this, the aim was to evaluate the wine protection by oenological tannins against an another disease, the downy mildew. METHODS: During the 2020 vintage, infected grapes by downy mildew (Vitis vinifera cv. Merlot) were collected from the dispositive ResIntBio. The 100 kg were crushed, destemmed and dispatch into 10 aluminium tanks. SO2 was added at 3 g/hL. Oenological tannins (grape, quebracho, ellagitannin or gallotannin) were added at 100 g/hL into eight different tanks (4×2 tanks). The two last tanks were considered as control without addition of oenological tannins. Alcoholic fermentation was achieved with Actiflore 33® at 20 g/hL. Malolactic fermentation was achieved with Lactoenos B7at 1 g/hL. Finished wines were sulfited to obtain 45 mg/L of total SO2.

Read More

Non-saccharomyces yeasts in the biocontrol of grape molds in vineyards to reduce the use of pesticides

The wide diffusion of organic cultivation of vineyards and the need to reduce the use of pesticides highlights the urgent need for alternative and sustainable methods of vine protection by pathogen molds.

Read More

Pesticide – Free viticulture: towards agroecological wine-producing socio-ecosystems

Can we cultivate grapevine without pesticides? This is a huge challenge for this emblematic crop, which is one of the largest users of plant protection products. Pesticides are mainly used to protect the vine against leaf diseases (powdery mildew, mildew, black-rot), even in organic farming, which uses copper in particular. What are the research avenues that can help eliminate pesticides today?

Read More

Ten years soil diagnosis in vineyards, with particularly analysis of organic and microbial mass and measuring their evolution

Since 1996, we study the soil in viticulture, specially in the South of France. In the field, we delimit soil units and observe soil profiles and take samples to analyse its physical, mineral, organic and microbial mass composition

Read More