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…

Screening of hydroxytyrosol and tyrosine related metabolites in commercial wines by an UHPLC/MS validated method.

Hydroxytyrosol (HT) is a bioactive phenolic compound with antioxidant activity. Yeast synthetise tyrosol from tyrosine by the Ehrlich pathway which is subsequently hydroxylated to HT. The aim of the present work is to develop and validate an UHPLC–HRMS method to assess the metabolites involved in this pathway as well as to screen Spanish commercial wines for HT bioactive compound.

Which heat test can realistically estimate white wine haze risk?

Different heat tests are used to predict the dose of bentonite necessary to prevent wine haze after bottling. The most used tests are 60-120 min. at 80°C. Nevertheless, there is a lack of information about the relationship between these tests and the turbidities observed in the bottles after the storage/transport of the wines in realistic conditions, when temperatures reach 35-42°C during 3-12 days.

Effect of pH and ethanol on Lactiplantibacillus plantarum in red must fermentation: potential use of wine lees

Wine is the result of the alcoholic fermentation (AF) of grape must. Besides AF, wine can also undergo the malolactic fermentation (MLF) driven out by lactic acid bacteria (LAB). Among LAB, Oenococcus oeni and Lactiplantibacillus plantarum are the dominant species in wine. Even if O. oeni is the most common LAB undergoing MLF in wine, due to its high tolerance to wine conditions, L. plantarum can be used to undergo MLF in must. The moderate tolerance of L. plantarum to low pH and ethanol, may compromise the fermentative process in harsh wines.

Winter physiology in a warmer world: Cold hardiness and deacclimation sensitivity drive variation in spring phenology

As the climate warms, the focus of concern in viticulture often turns to how higher temperatures may shift growing regions, change the character of AVAs, and alter fruit quality. However, climate warming is increasing most quickly during the winter dormancy cycle, a critical and often underappreciated portion of the grapevine life cycle. In response to decreasing temperatures and decreasing daylength, grapes initiate a series of physiological changes to enter dormancy, acquire freeze resistance, and time spring phenology such that the growing season begins after threat of frost.

Specificities of red wines without sulfites: which role for acetaldehyde and diacetyl? A compositional and sensory approach.

Sulfur dioxide is the most commonly used additive in oenology to protect wine from oxidation and microorganisms. Once added to wine SO2 is able to react with carbonyl compounds to form carbonyl bisulfites what affects their reactivity.