Insights into the genetic and epigenetic regulation of budbreak in grapevine

Supervisor: prof.ssa Rachele Falchi
Co-tutor: prof. Emanuele De Paoli

In grapevine, phenological development is strongly affected by seasonal temperature fluctuations and environmental stimuli, making global warming one of the main factors threatening modern viticulture. Higher winter temperatures and warm spells lead to early budbreak, causing an anticipation of all developmental stages as well as the exposure of vulnerable tissues to spring frost events. Grapevine varieties show different budbreak timings but, due to their genetic adaptation to geographic regions, this variability is not enough to ensure effective responses to rapid and extreme environmental changes. Understanding the molecular regulation of dormancy and budbreak is therefore essential to direct breeding efforts towards the selection of cultivars better suited to the changing climate conditions. Previous transcriptome analysis highlighted the reactivation, during budbreak, of genes involved in epigenetic processes such as DNA methylation and histone modifications. Thus, the project proposes the implementation of complementary approaches, including RNA and chromatin sequencing carried out on buds at different developmental stages, to explore the landscape of genetic and epigenetic changes involved in the regulation of dormancy and budbreak, and to relate them to the observed variability between early- and late-budbreak varieties.