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…

Model-assisted analysis of the root traits underlying RSA genotypic diversity in Vitis: a promising approach for rootstock selection?

By dissecting the root system architecture (RSA) into its underpinning components (e.g. root emission, axial growth, radial growth, branching, root direction or tropism) and identifying the relationships between them, functional-structural 3D root models are promising tools for analyzing the diversity and complexity of root system phenotypes with Genotype × Environment interactions. The model parameters are assumed to be synthetic traits, less influenced by the environment, and consequently with less polygenic architectures than the integrative RSA traits they drive. Root models can serve as a basis for in silico development of root system ideotypes by highlighting the developmental processes and parameters that most likely influence RSA fitness.

The weak role of organic mulches in shaping bacterial communities in grapevine

The interest in sustainable and ecologic agricultural practices in grapevine has grown significantly in recent years in the context of ecological transition. Organic mulches are treatments that support the circular economy and positively affect the soil and the plant. They are an alternative to herbicides and other conventional practices since they may influence soil moisture, erosion, structure and weed control. However, their effects on the soil and must microbiota remain unknown.

Evaluation of the effects of pruning methodology on the development of young vines 

Grapevine pruning is one of the most important practices in the vineyards. Winegrowers use it to provide the vines the shape needed, or to maintain it once achieved, and also to balance vegetative growth and fruit production. In the last decades, careless pruning has been blamed, among other factors, as responsible of the vineyard decay that is been observed even in young vines. However, to our knowledge, there is a lack of systematic research trying to elucidate to which extent the pruning method used affects plant development or its susceptibility to grapevine trunk diseases (GTD). Within this context, the aim of this work is to study the influence of different pruning method strategies on the development of field-planted young vines.

The potential of some native varieties of Argentina for the production of sparkling wines. Effect of lees contact time 

Grapevine varieties from South-America, commonly known as criollas, originated because of the natural crossbreeding of grapevine varieties brought by the Spaniards. The objective of this work was to evaluate the potential of some varieties to produce sparkling wines considering the effect of lees contact time. The following varieties were used: Moscatel Rosado, Criolla Chica, Pedro Gimenez, Blanca Oval, Canelón, and the European variety Chardonnay (control), planted in the ampelographic collection of EEA Mendoza INTA (Argentina). Pilot-scale vinifications were carried out to obtain the base wines, in 20 L glass containers. The second fermentation was performed through the traditional method.

Yeast mannoprotein characterization and their effect on Oenococcus oeni and malolactic fermentation

Mannoproteins are released at the end of alcoholic fermentation due to yeast autolysis [1]. It has been described a positive effect of these molecules on lactic acid bacteria growth [2]. The main objective of this work was the characterization of different mannoproteins extracted from active dry yeast (ADY) and the assessment of their effect on Oenococcus oeni and malolactic fermentation (MLF).