Perspectives for molecular-based phenological modelling: the example of two models developed for sweet cherry bud dormancy

Global climate change is associated with increasing temperatures and therefore strong impacts on the timing of phenology in perennial plants. In particular, the damages caused by late spring frosts and/or incomplete dormancy release are already dramatically impact growth and production and cause tremendous economic losses. These consequences are predicted to increase in the next decades. Therefore, it is key to anticipate these impending changes and to assess the impacts of future climatic conditions on phenology of perennial fruit trees. With the rise of high-throughput genotyping and phenotyping, there is increasing potential to integrate the recent understanding of signaling pathways into phenology models, in order to simulate the impact of environmental conditions on phenophases, especially winter bud dormancy. Here, I present two different modelling approaches developed for sweet cherry bud dormancy based on transcriptomic and metabolomics data: 1) an untargeted modelling approach, i.e. the prediction of dormancy stages based on expression pattern for all expressed genes, without any prior knowledge on the mechanisms involved in dormancy and 2) a targeted modelling approach where candidate genes and signaling pathways have been selected beforehand and are used to build and validate a predictive model for dormancy status. I successfully predicted dormancy stages using a small set of genes. Such integrative approaches are extremely useful for the development of diagnostic tools and a better comprehension of complex phenological processes.