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…

Effect of polysaccharide extracts from grape pomace on the oxidative evolution of hydroxycinnamic acids

Phenolic acids are especially sensitive to oxidation, so they can greatly impact wine sensory characteristics and stability [1]. Furthermore, extracts derived from grape pomace have been previously postulated as possible oenological adjuvants for wine protection [2].

The role of climate/soil of different zones/terroirs on grape characteristics

According to the different concern of the ‘traditional’ and the ‘new’ wine-producing Countries, a variable importance is recognized to the climate/soil and to grapevine cultivars as factors affecting the wine quality. However, the viticultural experience can state that, within each area, climate and soil plays an incontestable role in affecting grape quality, and consequently wine quality, as well as the genetic characteristics of the cultivar.

Identification of key-odorants in Sauternes Wines

The aim of the present work was to investigate Sauternes wines aromas. The flavor profiles of two wines (vintages 2002 and 2003) were investigated. Key-odorants have been determined by AEDA applied to Amberlite XAD-2 resin extracts. Various complementary techniques were used to identify the compounds (pHMB extraction, chemical synthesis of non-commercial standards, co-injections on two capillary columns, odor description at the sniffing port, GC-MS and GC-PFPD).

Multi-trait selection in ancient grapevine varieties

The selection of ancient grapevine varieties aims to achieve genetic gains in several important traits that can make the variety more interesting for the objectives of the producers. Traditionally, yield and quality traits of the must have been considered for selection, but many others can be taken into account. Linear mixed models are fitted to the data to predict the empirical best linear unbiased predictors (EBLUPs) of genotypic effects for each evaluated trait, which will be the basis for selection.

Quantification of newly identified C8 aroma compounds in musts and wines as an analytical tool for the early detection of Fresh Mushroom Off-Flavor

The Fresh Mushroom Off-Flavor (FMOff) is a concerning undesirable aroma in wine specific of certain vintages, characterized by a typical button mushroom aroma. The appearance of this off-flavor is linked to the presence of certain fungus on the grape [1-3].