terclim by ICS banner
IVES 9 IVES Conference Series 9 Mgaloblishvili Rpv29 and Rpv31 loci reveal new insights on downy mildew resistance sources in Vitis vinifera

Mgaloblishvili Rpv29 and Rpv31 loci reveal new insights on downy mildew resistance sources in Vitis vinifera

Abstract

Downy mildew, a disease caused by Plasmopara viticola (Berk. et Curt.) Berl. and De Toni, is one of the strongest threats to grapevine (Vitis vinifera L.) production. Recently, sources of resistance to downy mildew were identified among Caucasian germplasm. Among them, the Georgian variety Mgaloblishvili revealed a unique resistance mechanism. A genome wide association study (GWAS) allowed the identification of the genetic bases of Mgaloblishvili resistance, the loci Rpv29, Rpv30 and Rpv31. To dissect the three resistance loci, Mgaloblishvili genome was sequenced using PacBio HiFi reads and assembled. A chromosome-scale diploid genome assembly consisting of ~ 986 Mb and a contig N50 length of 25.8 Mb was obtained. A total of 58,912 protein-coding genes were predicted on the two sets of phased chromosomes. A whole genome comparison with the genome of the susceptible reference accession PN40024 was performed. Mgaloblishvili resistance loci were in-depth analyzed in terms of structure, gene content, gene expression and impact of structural variants (SVs) and SNPs (Single Nucleotide Polymorphisms). Furthermore, using DNA sequencing data of Mgaloblishvili self-cross progeny, resistance haplotypes were identified for Rpv30 and Rpv31. The obtained data highlighted Mgaloblishvili resistant phenotype as a consequence of multiple small SVs and SNPs, that eventually results into differential transcriptional regulation. Altogether, these genetic resources will increase the knowledge about downy mildew-grapevine pathosystem. Moreover, they will be available for breeding programs aiming to develop grapevine resistant varieties.

DOI:

Publication date: June 13, 2024

Issue: Open GPB 2024

Type: Article

Authors

Valentina Ricciardi 1, Andrea Minio 2, Melanie Massonnet 2, Alexander H.J. Wittenberg3, David Maghradze 4,5,6, Silvia Laura Toffolatti 1, Osvaldo Failla 1, Dario Cantù 2*, Gabriella De Lorenzis

1 Department of Agricultural and Environmental Sciences, University of Milan
2 Department of Viticulture and Enology, University of California, Davis (CA), USA
3 KeyGene, Wageningen, The Netherlands
4 Caucasus International University, Tbilisi, Georgia
5 Georgian Technical University, Tbilisi, Georgia
6National Wine Agency of Georgia, Tbilisi, Georgia

Contact the author*

Keywords

Grapevine, biotic stress, QTL, genome, Caucasus

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

PHOTO OXIDATION OF LUGANA WINES: INFLUENCE OF YEASTS AND RESIDUAL NITROGEN ON VSCS PROFILE

Lugana wines are made from Turbiana grapes. In recent times, many white and rosé wines are bottled and stored in flint glass bottles because of commercial appeal. However, this practice could worsen the aroma profile of the wine, especially as regards the development of volatile sulfur compounds (VSCs). This study aims to investigate the consequences of exposure to light in flint bottles on VSCs profile of Lugana wines fermented with two different yeasts and with different post-fermentation residual nitrogen.

Activation of retrotransposition in grapevine

Retrotransposons, particularly of the Ty-Copia and Ty-Gypsy superfamilies, represent the most abundant and widespread transposons in many plant genomes. Grapevine is no exception and it is clear that these mobile elements have played a major role in the evolution of Vitaceae genomes. While speculation abounds around the possible role of transposons in plant genomes, outside of the rather obvious involvement of retrotransposition in fueling genome expansion, there is little clarity of the actual role these elements have in both developing new genetic variation and in modulating epigenetic responses within genomes to changing climate. To this end we have been exploring de-novo assembled Sauvignon blanc and Pinot noir genomes with a view to catalogue retrotransposon loci to determine the structural intactness and thus age of insertion variation across a small number of clonal linages of these 2 varietals in an attempt to identify ‘live’ TE loci.

DNA and type of grain: which factor does better explain sensory differences of sessile and pedunculate oaks?

Sessile oak and pedunculate oak have shown several differences of interest for enological purposes. Tannic and aromatic composition among sessile oak or pedonculate oak has been well studied. Sessile oak is generally more aromatic than pedunculated, while the later is more tannic. This scientific point of view is rarely applied to classify oak in cooperages. Most coopers use the type of grain to distinguish wide and thin grain.

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.

Study of the “Charentes terroir” for wine production of Merlot and Sauvignon: method, installation of the experimental device, first results

Cognac vineyard is mainly dedicated to brandy production. Within the vineyard restructuring context, one part is turned over wine varieties for wine production (about 1,500 ha planted from 1999 to 2005). Today, the new wine producers need technical references about qualitative potential of the « Charentes Terroir », varieties and adapted vineyard management.
In order to answer to this professional request, an observatory of 18 plots of Merlot and 12 plots of Sauvignon have been laid out since 2003 and 2004 on various kinds of pedoclimate.