Technical Yearbook 2024

FIGURE 1. An overview of the Pinotage Diversity Project and a timeline of completed, current and future stages of the project.

compared to non-irradiated vines was observed in the early stages of the season, although there were differences between clones. • The ripening period of the grapes was significantly altered, with some individuals showing earlier and later ripening periods than the commercially available clones. • The population showed many phenotypic differences. The first bunch and berry characteristics observed point to an interesting mix of potentially valuable phenotypes, particularly regarding bunch architecture (looser bunches), bunch and berry sizes, as well as berry skin and flesh colours (Figures 2 and 3) and the overall growth and fruitfulness of the plants. • Overall, increased variation was observed in most parameters analysed in the irradiated populations. • The data obtained corroborate existing literature that indicates that gamma irradiance can be an effective mechanism to induce mutations in plants. The phenotypic differences observed included: • Very large or very small canopies. • Very bushy or very upright growth habits. • Loose to very compact berry clusters.

FIGURE 2. An example of differences in berry size observed.

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TECHNICAL YEARBOOK 2024