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…

Sensory profile of wines obtained from disease-resistant varieties in La Rioja

The European wine industry is facing multiple challenges derived from climate change and the pressure of different fungal diseases that are compromising the production of traditional varieties. A sustainable alternative maybe the adoption of resistant varieties.
In this study, we have evaluated the enological potential of 9 resistant varieties (5 white and 4 red varieties) in La Rioja. Microvinifications were carried out with three biological replications. Oenological parameters were very diverse with acid content varying from 2.6 g/L to 6.6 g/L.

Understanding the impact of rising temperatures due to climate change on aromatic compositions in Malbec wines from Mendoza, Argentina

Mendoza is one of Argentina’s most important and outstanding wine regions producing the renowned Malbec wines due to its optimal soil and weather conditions. However, the effects of 21st-century climate change would negatively impact Malbec wines quality. This study investigated the effect of temperature increase and the impact of plant hormone abscisic acid (ABA) used to mitigate the negative effect of temperature increase on Malbec wines aromatic composition through GC-MS. Four treatments were applied on vines at field condition: Control, Control + 3 ºC, ABA and ABA + 3 ºC.

is the overall ecological awarness among Spanish winemakers related to their attitudes towards natural wines?

The Agenda 2030 of the EU sets out the main guidelines for transitioning towards a resilient, green and safe economy. To this regard, the wine sector is experiencing an ecological transition in different ways such as increasing the production of ecological crops, or promoting the production of wines under more environmental-friendly and healthier (i.e., lower levels of SO2) products. These alternatives to conventional production are a smaller proportion of wines, in constant growth and demand, and follow alternative and minority practices, which range from sustainable to deeply philosophical thoughts. Among these methods there are organic, biodynamic and, more recently, natural wines.

Drought responses of grapevine cultivars under different environments

Using grapevine genetic diversity is one of the strategies to adapt viticulture to climate change. In this sense, assessing the plasticity of cultivars in their responses to environmental conditions is essential. For this purpose, the drought tolerance of Grenache, Tempranillo and Semillon cultivars grafted onto SO4 was evaluated at two experimental vineyards, one located in Valencia (Spain) and the other in Bordeaux (France). This was done by assessing gas exchange parameters, water relations and leaf hydraulic traits at the end of the season.

Tackling the 3D root system architecture of grapevines: a new phenotyping pipeline based on photogrammetry

Plant roots fulfil important functions as they are responsible for the acquisition of water and nutrients, for anchorage and stability, for interaction with symbionts and, in some cases, for the storage of carbohydrates. These functions are associated with the Root System Architecture (RSA, i.e. the form and the spatial arrangement of the roots in the soil). The RSA results from several biological processes (elongation, ramification, mortality…) genetically determined but with high structural plasticity.