Prospects for applications of genomic tools in registration testing and seed certification of ryegrass varieties

The ryegrass ( Lolium ) species, perennial ryegrass ( Lolium perenne L.) and Italian ryegrass ( Lolium multiflorum Lam.), are the two most important pasture grass species for global temperate regions and are also useful for amenity purposes. Due to an outbreeding reproductive habit, high levels of genetic heterogeneity are present within cultivated varieties. A continual increase in delivery of new cultivars to the marketplace, along with limited capacity to discriminate on the basis of morphological characteristics in a grow‐out test, has caused difficulties for distinctness, uniformity and stability ( DUS ) testing in the current plant variety protection ( PVP ) system. A range of genomic tools and resources have been generated for ryegrasses, which provide new opportunities and challenges to the current PVP system. In this review, the currently available genomic tools and resources are described, along with prospects for applications to the PVP system and testing for seed certification and purity accreditation.