terclim by ICS banner
IVES 9 IVES Conference Series 9 International Congress on Grapevine and Wine Sciences 9 2ICGWS-2023 9 Identification of loci associated with specialised metabolites in Vitis vinifera

Identification of loci associated with specialised metabolites in Vitis vinifera

Abstract

Secondary (or specialised) metabolites such as terpenes and phenolic compounds are produced by plants for various roles which include defence against pathogens and herbivores, protection against abiotic stress, and plant signalling. Additionally, these metabolites influence grapevine quality traits such as colour, aroma, taste, and nutritional value. However, the biosynthesis of these metabolites is often complex and controlled by multiple genes which in grapevine are predominantly uncharacterised. This study therefore aimed to identify novel loci associated with grapevine volatile organic and phenolic compounds. Chemical analysis of these compound classes was performed via GC-MS and UPLC analysis in a grapevine mapping population, and the quantified metabolites used for quantitative trait loci (QTL) analysis.  Several significant QTLs associated with terpenes and phenolic compounds were identified, and the underlying genomic regions were investigated. For phenolic compounds, a novel locus associated with caftaric acid biosynthesis was identified, and a hydroxycinnamoyltransferase (VvHCT) was investigated as a candidate gene. Several terpene synthases (VvTPSs) co-localised with QTLs associated with monoterpenes and sesquiterpenes. Notably, loci on chromosomes 12 and 13 were shown to be associated with geraniol and cyclic monoterpene accumulation, respectively. The locus on chromosome 12 was shown to contain a geraniol synthase gene (VvGer), while the locus on chromosome 13 contained an a-terpineol synthase gene (VvTer). Further molecular and genomic investigation of VvGer and VvTer found that these genes appear in tandemly duplicated clusters, with high levels of hemizygosity which was further supported by genomic data from recently published diploid grapevine genomes. Interestingly, copy number analysis demonstrated that VvTer gene copy number correlated with both VvTerexpression and the accumulation of cyclic monoterpenes, highlighting the impact of VvTPS gene duplication and copy number variation on terpene accumulation in grapevine.

DOI:

Publication date: October 3, 2023

Issue: ICGWS 2023

Type: Article

Authors

Robin Bosman*1 and Justin Graham Lashbrooke2

1South African Grape and Wine Research Institute, Stellenbosch University, Stellenbosch, South Africa
2 Department of Genetics, Stellenbosch University, South Africa.

Contact the author*

Keywords

terpenes, TPS, grapevine, gene copy number, genomics, QTL, phenolics

Tags

2ICGWS | ICGWS | ICGWS 2023 | IVES Conference Series

Citation

Related articles…

Vertical cordon training system enhances yield and delays ripening in cv. Maturana Blanca

The growing interest in minority grape varieties is due to their potential for adaptation to global warming and their oenological capabilities. However, the cultivation of these varieties has often been limited due to their low economic efficiency. One such example is Maturana Blanca, a recently recovered and authorized minority grape variety in the DOCa Rioja region, known for its remarkable oenological potential but low productivity. This study aimed to increase the yield of Maturana Blanca by implementing the vertical cordon training system, which allowed for a higher number of buds per plant and an increased cluster count per vine.

Applicability of grape native yeasts to enhance regional wine typicity

The universalization in wine production has been restricting the imprint of terroir in regional wines, resulting in loss of typicity. Microbes are the main driving force in wine production, conducting fermentation and originating a myriad of metabolites that underly wine aroma. Grape berries harbor an ecological niche composed of filamentous fungi, yeasts and bacteria, which are influenced by the ripening stage, cultivar and region. The research project GrapeMicrobiota gathers a consortium from University of Zaragoza, University of Minho and University of Tours and aims at the isolation of native yeast strains from berries of the wine region Douro, UNESCO World Heritage, towards the production of wines that stand out in the market for their authenticity and for reflecting their region of origin in their aroma.

Effect of irrigation in cover cropping vineyards

Cover cropping in vineyard is a sustainable and alternative soil management system to conventional tillage that is gaining more and more importance among winegrowers and is being promoted, among other organizations, by the European Union through the eco-schemes of the Common Agricultural Policy.
However, the use of cover crops in Mediterranean viticultural environments is conditioned, to a large extent, by the availability of irrigation water which, in a context of global warming like the one we are experiencing, must be adjusted to savings strategies, supplying to the vine only what it needs in each moment.

Effect of spray with autochthonous Trichoderma strains and its secondary metabolites on the quality of Tempranillo grape

Trichoderma is one of the most widely used fungal biocontrol agents on vineyards due to its multiple benefits on this crop, such as its fungicidal and growth promoting capacity. In this work, we have analyzed the effect on the concentration of nutrients in grapevine leaves and on the quality of the grape must after spraying an autochthonous strain of Trichoderma harzianum and one of the main secondary metabolites produced by this genus, 6-pentyl-α-pyrone (6PP).

Cumulative effect of deficit irrigation and salinity on vine responses

Climate change is increasing water needs in most of the wine growing regions while reducing the availability and quality of water resources for irrigation. In this context, the sustainability of Mediterranean viticulture depends on grapevine responses to the combinations of water and salt stress. With this aim, this work studies the effects of deficit irrigation and salinity on the physiology of the Tempranillo cultivar (Vitis vinifera L.) grafted onto a drought and salinity tolerant rootstock (1103 Paulsen).