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.

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…

Effect of Botrytis cinerea and esca on phenolic composition of berries and wines

This study showed that Botrytis cinerea could degrade the phenolic compounds by its enzymatic activity. It led to a diminution of skin’s anthocyanins from 20 % to 50 % and an increase level up to 40 % of individual proanthocyanins, 30 % of the %G and 25% of the %P.

IMPACT OF FINING WITH K-CARRAGEENAN, BENTONITE, AND CHITOSAN ON PROTEIN STABILITY AND MACROMOLECULAR COMPOUNDS OF ALBARIÑO WHITE WINE PRODUCED WITH AND WITHOUT PRE-FERMENTATIVE SKIN MACERATION

Pre-fermentative skin maceration is a technique used in white wine production to enhance varietal aroma, but it can increase protein concentration, leading to protein instability and haze formation [1]. To prevent protein instability, wine producers typically use fining agents such as bentonite, before wine bottling, which can negatively impact sensory characteristics and produce waste [2,3]. The aim of this study was to understand the impact of alternative techniques such as the application of polysaccharides (k-carrageenan and chitosan) on protein stability and on the wine macromolecular composition.

The impact of sustainable management regimes on amino acid profiles in grape juice, grape skin flavonoids, and hydroxycinnamic acids

One of the biggest challenges of agriculture today is maintaining food safety and food quality while providing ecosystem services such as biodiversity conservation, pest and disease control, ensuring water quality and supply, and climate regulation. Organic farming was shown to promote biodiversity and carbon sequestration, and is therefore seen as one possibility of environmentally friendly production. Consumers expect organically grown crops to be free from chemical pesticides and mineral fertilizers and often presume that the quality of organically grown crops is different or higher compared to conventionally grown crops. Integrated, organic, and biodynamic viticulture were compared in a replicated field trial in Geisenheim, Germany (Vitis vinifera L. cv. Riesling). Amino acid profiles in juice, grape skin flavonoids, and hydroxycinnamic acids were monitored over three consecutive seasons beginning 7 years after conversion to organic and biodynamic viticulture, respectively. In addition, parameters such as soil nutrient status, yield, vigor, canopy temperature, and water stress were monitored to draw conclusions on reasons for the observed changes. Results revealed that the different sustainable management regimes highly differed in their amino acid profiles in juice and also in their skin flavonol content, whereas differences in the flavanol and hydroxycinnamic acid content were less pronounced. It is very likely that differences in nutrient status and yield determined amino acid profiles in juice, although all three systems showed similar amounts of mineralized nitrogen in the soil. Canopy structure and temperature in the bunch zone did not differ among treatments and therefore cannot account for the observed differences in favonols. A different light exposure of the bunches in the respective systems due to differences in vigor together with differences in berry size and a different water status of the vines might rather be responsible for the increase in flavonol content under organic and biodynamic viticulture.

Histoire des Vitis depuis leurs origines possibles sur la Pangée jusqu’aux cépages cultivés : un exemple de résilience liée à la biodiversité des espèces

The first forms of life on earth were bacteria and single-celled blue-green algae. They evolved into land plants around 500 million years ago, developing mechanisms for surviving on land, such as roots, stems and leaves. This evolution also led them to coexist with other organisms, such as insects and animals, for pollination and seed dispersal, as well as to resist environmental factors such as drought and disease.

Elucidating contributions by vineyard site on volatile aroma characteristics of pinot noir wines

Correlations between vineyard site and wine have, historically, been limited due to lack of uniformity in scion and rootstock clone and lack of controlled pilot-scale winemaking conditions, particularly temperature