terclim by ICS banner
IVES 9 IVES Conference Series 9 Exogenous dsRNA applications to identify novel candidate susceptibility genes to downy mildew

Exogenous dsRNA applications to identify novel candidate susceptibility genes to downy mildew

Abstract

One of the major threats to viticulture is represented by fungal pathogens. Plasmopara viticola, an oomycete causinggrapevine downy mildew, is one of the principal causes of grape production losses. The most efficient management strategies are represented by a combination of agronomical practices, fungicides’ applications, and use of resistant varieties. Plant resistance is conferred by the presence of resistance (R) genes. Opposed to them, susceptibility (S) genes are encoded by plants and exploited by pathogens to promote infection. Loss or mutation of S genes can limit the ability of pathogens to infect the host. By exploiting post-transcriptional gene silencing, known as RNA intereference (RNAi), it is possible to knock-down the expression of S genes, promoting plant resistance. Gene silencing is induced upon exogenous application of dsRNA, which can interfere with protein synthesis. With the aim of identifying new candidate genes to be employed in breeding programs, three novel candidate S genes to downy mildew, VviLBDIf7, VviAS1 and VviB3, have been identified. Candidates’ validation was carried out through RNAi on the susceptible cultivar Pinot noir. Disease severity was estimated by experimental inoculation of P. viticola on leaves sampled at different timepoints after the treatment with dsRNA, while gene expression was evaluated by real time RT-PCR. Successful downregulation of candidate genes resulted in a significant reduction of plants susceptibility to downy mildew, suggesting our candidates as downy mildew S genes, leading to the possibility of employing an RNAi-based strategy as a more sustainable alternative to conventional management strategies.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Elisabetta Sergi1*, Giuliana Maddalena1, Valentina Ricciardi1, Demetrio Marcianò1, Beatrice Lecchi1, Osvaldo Failla1, Silvia Laura Toffolatti1, Gabriella De Lorenzis1

1 Affliliation Department of Agricultural and Environmental Sciences, via G. Celoria 2, 20133 Milan (Italy)

Contact the author*

Keywords

S genes, RNAi, gene silencing, Plasmopara viticola, Vitis vinifera

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Evolution of oak barrels C-glucosidic ellagitannins

During oak wood contact, wine undergoes important modifications that modulate its organoleptic quality and complexity, including its aroma, structure, astringency, bitterness and color. Vescalagin and castalagin are the two main C-glucosidic ellagitannins found in oak wood used for wine aging wood but lyxose/xylose derivatives (grandinin and roburin e) and dimeric forms (roburins a,b, c and d) are also present. The presence of several hydroxyl groups in the ortho-positions at the periphery of the structure of the ellagitannin isomers allows these molecules to undergo oxidation or condensation reactions with other compounds.

Identification of compounds produced by reactions of flavonoids and acetaldehyde in wine

During aging, wine consumes small amounts of oxygen. This oxygen intake triggers a series of reactions that lead to flavonoid elongation, which is known to reduce bitterness and astringency while enhancing color stability.

Towards more coherent rules for alcohol labelling in the European Union

In its 2020 beating cancer plan, the european commission announced plans for mandatory warning signs for alcoholic beverages. However, no concrete legislative proposal has been put forward so far. Instead, ireland passed national legislation in 2023 that requires warning signs for all alcoholic beverages from 2026. Despite significant effects for the common market, the eu commission did not this challenge this law in the so-called tris notification procedure. We argue that the commission’s inaction is consistent with the case law of the european court of justice: in the absence of harmonized rules, member states have a large margin of discretion to enact national health measures.

THE EFFECT OF BENTONITE FINING ON THE VOLATILE AND NON-VOLATILE PROFILE OF ITALIAN WHITE WINES

Marselan wines have an unusual high proportion of seed derived tannins from grapes having high proportions of skins, which are rich in tannins. But the causes behind this characteristic have not yet been identified. In vintage 2023 wines were made at experimental scale (9 kg by experimental unit) from Arinarnoa, Marselan and Tannat Vitis vinifera grape cultivars by traditional maceration, and by techniques aimed to increase the wine content in skin derived tannin: addition of extraction enzymes, addition at vatting of grape-skin enological tannins, or by extended maceration, known to increase the seed derived tannin contents of wines. Macerations were of 7 days, except in the extended macerations that were of 15 days.

Gestión de la mitigación por las empresas vitivinícolas: combinar sostenibilidad y rentabilidad

The transition to a decarbonized economy requires companies to adopt mitigation measures. The wine sector is one of the most affected by climate change and, therefore, interested in its mitigation. The question is how this process develops. To address this, we build on a previous study [1], which identified different types of Spanish wineries based on their sustainability approach.