terclim by ICS banner
IVES 9 IVES Conference Series 9 Molecular characterization of a variegated grapevine mutant cv Bruce’s Sport

Molecular characterization of a variegated grapevine mutant cv Bruce’s Sport

Abstract

Variegation, a frequently observed trait in plants, is characterized by the occurrence of white or discoloured plant tissue. This phenomenon is attributed to genetic mosaicism or chimerism, potentially impacting the epidermal (L1) and subepidermal (L2) cell layers. In grapevine, variegation manifests as white or paler leaf, flower, or berry tissues, often leading to stunted growth and impeded development. Despite its prevalence, variegation in grapevines remains understudied. Notably, a natural mutant derived from Sultana, namely Bruce’s Sport, exhibits colour variegation in the leaves, although this occurrence only appears later in the growing season. Conversely, the flowers and berries are always variegated and are paler in colour. Furthermore, studies have observed that Bruce’s Sport displays a lower berry yield compared to the Sultana variety, along with reduced polyphenol oxidase (PPO) activity in the variegated tissues. This study aims to investigate the genetic basis of variegation in Bruce’s Sport and its effects on plant growth and development. To this extent, a transcriptomic analysis was employed comparing data obtained from flower tissue of Sultana and Bruce’s Sport. Additionally, differentially expressed genes were confirmed, aiding in the identification and characterization of genes associated with variegation in the Vitis genome, potentially uncovering candidates for future functional studies.

DOI:

Publication date: June 14, 2024

Issue: Open GPB 2024

Type: Poster

Authors

Clara Holm1*, Nina Wiese1, Manuela Campa1, Johan Burger1, Justin Lashbrooke1

1 Genetics Department, Stellenbosch University, South Africa

Contact the author*

Keywords

variegation, grapevine, polyphenol oxidase activity, gene expression

Tags

IVES Conference Series | Open GPB | Open GPB 2024

Citation

Related articles…

Rapid optical method for tannins estimation in red wines

In this work, an innovative analytical method has been proposed for fast and reliable in-line analysis of tannins in wines; the method is fast, does not require sample preparation and is based on the selective reactivity of tannins in a mixture containing proteinaceous matter (i.e. gelatin), under pH 3.5, resulting in the formation of white cloudiness.

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.

Variety specific thresholds for plant-based indicators of vine nitrogen status

Aim: Several plant-based indicators of vine N status are reported in the literature. Among these, yeast assimilable nitrogen in grape must (YAN) and total N concentration of petiole and leaf blades are considered to be reliable indicators and so is the chlorophyll index, measured with a device called N-tester. The N-tester index is used to measure the intensity of the green colour of the leaf blade, and therefore to estimate its chlorophyll content.

Relationships between vine isohydricity and changes of fruit growth and metabolism during water deficit

The frequency of water deficits is increasing in many grape-growing regions due to climate change.

The real sour grapes: genetic Loci, genes, and metabolic changes associated with grape malate levels

Insufficient levels of malate and lack of acidity in commercial grape cultivars (V.vinifera) hinders the quality of fruit grown in warm climates. Conversely, excessive levels of malate and sourness in wild Vitis grape, leads to unpalatable fruit and complicates the introgression of valuable disease resistant alleles through breeding. Nonetheless, albeit decades of research, knowledge regarding the molecular regulation of malate levels in grape remains limited.