terclim by ICS banner
IVES 9 IVES Conference Series 9 EVALUATION OF A SEAWEED EXTRACT OF RUGULOPTERYX OKAMURAE AGAINST ERYSIPHE NECATOR IN GRAPEVINE

EVALUATION OF A SEAWEED EXTRACT OF RUGULOPTERYX OKAMURAE AGAINST ERYSIPHE NECATOR IN GRAPEVINE

Abstract

Powdery mildew, caused by Erysiphe necator, is a widespread disease that causes high economical losses in viticulture. The main strategy to control the disease is the recurrent application of sulphur based phytochemical compounds. However, in order to reduce their accumulation in the environment and promote the sustainability of the sector, the European Commission has applied restrictions to the number of pesticide treatments and the maximum quantity of fungicides to be applied in viticulture. Seaweeds, in particular macroalgae, are marine resources rich in sulphated polysaccharides with bio-protective potential for the plant, representing an environmentally-friendly alternative approach for sustainable wine production.

In the current work we investigated the antifungal efficacy of the brown invasive macroalgae Rugulopteryx okamurae against Erysiphe necator. Rugulopteryx was collected from Algeciras coast (South Spain) and an aqueous extract was developed using a water /ethanol extraction protocol. A foliar spraying (6 gr/L) of Rugulopteryx okamurae extract was applied to Tempranillo and Cabernet Sauvignon plants grown in a green-house facility and the antifungal activity of the extract was tested by monitoring disease symptoms after fungi infection. Results showed that while the incidence of powdery mildew was similar in treated than in control plants (water treated), the disease severity was 1.7 fold lower for treated plants in comparison to controls. Further research by exploring grapevine resistance/defence mechanisms is necessary to explain this extract´s mode of action.

Evidencing the efficacy of Rugulopteryx okamurae as a biostimulant/fungicide is a finding of major importance, as it would be a first step towards its inclusion in a circular scheme, reducing its accumulation on the coast and at the same time benefiting the wine sector.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

Anthony Pébarthé-Courrouilh1,2, Stéphanie Cluzet1,2, Iratxe Zarraonaindia3,4, Emma Cantos-Villar5*

1. Univ. Bordeaux, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33140 Villenave d’Ornon, France
2. Bordeaux Sciences Agro, Bordeaux INP, INRAE, OENO, UMR 1366, ISVV, F-33170 Gradignan, France
3. Department of Genetics, Physical Anthropology and Animal Physiology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa (Bizkaia), Spain.
4. IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
5. IFAPA Rancho de la Merced, Consejería de Agricultura, Pesca, Agua y Desarrollo Rural, Junta de Andalucía, 11471 Jerez de la Frontera, Cádiz, Spain.

Contact the author*

Keywords

sustainability, Fungicides, seaweed, circular economy

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

A NEW STRATEGY AND METHODOLOGY FOR THE CHARACTERIZATION OF POLYPHENOLS IN FINING PRECIPITATE

Polyphenols are secondary metabolite widely distributed in plant kingdom such as in fruits, in grapes and in wine. During the winemaking process, polyphenols are extract from the skin and seed of the berries. Fining is an important winemaking step just before bottling which has an impact on wine stabilization and clarification. Most the time, fining agent are animal or vegetal protein while some of them can be synthetic polymer like PVPP or natural origin like bentonite.

DOES LIGNIN AN ACCEPTABLE MARKER OF GRAPESEED MATURATION AND QUALITY?

Usually the winemaker consider polyphenols from the grape berry as an actor of the wine quality. There are frequently consider as a marker of grape maturity. It is commonly known that winemaker consider tannins and anthocyanins as main polyphenol actors for winemaking practices and wine quality. Here we will focus on the characterisation of lignins in grape seeds. Previous studies suggest that the seed is lignified [1], which could explain the change in colour of the seed when it reaches maturity and thus provide a reliable indicator for describing the maturity stage in the seed.

MOUSY OFF-FLAVOURS IN WINES: UNVEILING THE MICROORGANISMS BEHIND IT

Taints and off-flavours are one of the major concerns in the wine industry and even if the issues provoked by them are harmless, they can still have a negative impact on the quality or on the visual perception of the consumer. Nowadays, the frequency of occurrence of mousy off-flavours in wines has increased.
The reasons behind this could be the significant decrease in sulphur dioxide addition during processing, the increase in pH or even the trend for spontaneous fermentation in wine. This off-flavour is associated with Brettanomyces bruxellensis or some lactic acid bacteria metabolisms.

A synthesis approach on the impact of elevated CO2 on berry physiology and yield of Vitis vinifera

Besides the increase in global mean temperature the second main challenge of a changing climate is the increase in atmospheric carbon dioxide (CO2) in relation to physiology and yield performance of grapevines. The benefits of increasing CO2 levels under greenhouse environment or open field studies have been well investigated for various annual crops. Research under free carbon dioxide enrichment on field-grown perennial plants such as grapevines is limited to a few studies. Further, chamber and greenhouse experiments have been conducted mostly on potted vines under eCO2 conditions.

OENOLOGICAL STRATEGIES FOR THE REMOVAL OF PINKING IN WHITE WINE

The pinking of in white wine is the turning of color from yellow to salmon hue. White wines obtained from certain grape varieties (e.g. Chardonnay, Sauvignon blanc, Riesling, Trebbiano di Lugana) showed to be susceptible to pinking [1] that has been evaluated by an assay providing the addition of hydrogen peroxide. Even if its appearance does not seem to affect the sensory properties [2], strategies are necessary for its removal. Nowadays, the treatment with polyvinylpolipirroline (PVPP) was reported to significantly decrease the pink color [3].