Résumé
This chapter presents how epigenetic mechanisms can play a part in the various stages of a selection scheme and contribute to plant improvement, using the example of two agronomic species with very different characteristics: rice and grapevine. The use of epigenetic variations in plant breeding presents the problem of recognizing these variations as a stable trait enabling a new variety to be distinguished. Agronomic, technological and environmental value is another important criterion before a new variety can be registered in the official catalog and marketed. Beyond the regulatory aspect (tested in multilocation trials), the adaptation of a new rice or grape variety to its target environment is an essential aspect for its adoption by rice farmers or winegrowers. Genetics and epigenetics are intimately linked during varietal improvement processes. They must therefore be taken into account as explanatory factors. However, breeders are still reluctant to use epigenetic mechanisms in their day‐to‐day practices.