Epigenetics: an innovative lever for grapevine breeding in times of climatic changes

Climate change imposes numerous threats to viticulture. Different strategies have been developed to mitigate these effects that range from innovative vineyard management methods and precision viticulture to the breeding of new varieties and rootstocks better adapted to environmental challenges. Epigenetics refer to heritable changes in genome functioning that are not mediated by DNA sequence variations. The recent discovery that epigenetic memories can mediate acclimation and adaptation of plants to their environment now provides new levers for plant improvement facing climate changes without significant impact on the genetic information. This can be mediated either by using the epigenetic memories of stresses and/ or by creating epigenetic diversity in the form of new epialleles without changing the genetic information. Indeed, grapevine is a perennial grafted clonally propagated plant, and as such, presents epigenetic specificities. These specificities require adapting strategies that have already been developed in model plants but also offer opportunities to explore how epigenetic memories and diversity can be a major source of rapid adaptation to the environment for plants bearing similar properties. Among these strategies, both annual and trans-annual plant priming with different types of elicitors might provide efficient ways to better face (a)biotic stresses. The use of epigenetic exchanges between scion and rootstocks and/or the creation of non-targeted epigenetic variations at a genome-wide scale, or targeted using epigenetic editing, may provide innovative and promising avenues for grapevine improvement to face challenges imposed by climate changes.