Technical Yearbook 2024

FIGURE 3. Diversity of bunch architectures, skin and flesh colours, and pit characteristics observed in the population.

• Differences in berry size and shape. • Differences in skin and flesh colour.

cultivar has originated in South Africa and is widely planted. Although Pinotage already has fantastic attributes that need to be ‘kept’ in new clones, clonal material with a slightly different phenological progression, and specifically ripening progression, favourable wine pH, acid balance, as well as phenolic maturity (to name only a few), could provide valuable options to producers and winemakers in terms of Pinotage production and wine styles. The project’s outcomes would be new plant material, either in the form of novel Pinotage clones, potentially new cultivars (for example, a white Pinotage), or breeding lines with novel characteristics that can be used in the ongoing traditional breeding programme. All of these outputs will directly benefit the wine industry. The South African Pinotage Association supports the project in principle and financially. In addition, they provide all the wines needed to compare the chemical and sensory descriptions of the current Pinotage clones against the new material. The project also supports several postgraduate students participating in the research as part of their research activities towards their degrees. 

• Differences in seed number and appearance. In the irradiated population, individuals showed significant changes to the normal skin and flesh colour, particularly the emergence of fruit with highly pigmented flesh. This could be due to a higher anthocyanin accumulation in the flesh, like that of teinturier grapes. These promising results motivate a more in-depth analysis of the detailed phenology for the population, a time course analysis of the grapes’ ripening progression, and a chemical analysis of the berry ripening indicators. All these aspects form part of the project’s next phase, which is geared at evaluating the population to identify candidate individuals who can be further selected for more in-depth analyses after being grafted and propagated for further study on the plant

and wine level (Figure 1). Significance of the project

More options regarding Pinotage clonal diversity are essential for the South African wine industry since the

References https://www.wineland.co.za/research-update-the-quest-for-new-pinotage-clones/

For more information, contact Melané Vivier at mav@sun.ac.za.

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TECHNICAL YEARBOOK 2024