Breeding cereal rye (Secale cereale) for quality traits

Cereal rye (Secale cereale) is a multi-purpose crop, harvested for grain (for food, feed, and other products) as well as used as a forage or cover crop. The functionality of rye across these spheres is due to its abiotic and biotic stress tolerance and unique phytochemical composition. In this review, we focus on the current state and prospects of breeding rye for quality traits, where we define quality traits as grain, feed, or forage quality. Rye grain for human consumption has numerous healthful compounds, notably high dietary fiber content in grain and unique flavors that contribute to the signature properties of rye baked products and distilled spirits. As a forage, rye is useful in marginal environments and has high quality, including high crude protein, and is thus valuable for livestock production. While yield remains a major focus of breeding efforts, due to recent improvements in rye genomic and phenotypic resources, there are now opportunities for increased attention on breeding high-quality ryes for multiple end uses. Through genetic improvement of quality traits, cereal rye has the potential to expand and serve multiple markets as a climate-resilient crop.