Gene editing to support breeding in ornamental species

Breeding of ornamental species is primarily focused on creating new cultivars with unique ornamental value, and in recent years, developing resistance to pests and diseases has become increasingly important. Traditional breeding approaches, based on crossing and selection, can be made more efficient using marker-assisted selection. However, for many ornamental species, breeding remains challenging. The emergence of new plant breeding techniques, such as gene editing using CRISPR-Cas, holds great promise for supporting the breeding of ornamental crops. Targeted mutagenesis via gene editing can modify specific ornamental features without altering other unique cultivar characteristics. Additionally, by targeting susceptibility genes, gene editing can provide a new source of disease resistance. To realize these promises, several conditions must be met. For instance, the delivery of gene editing tools into plants depends on the availability of efficient transformation and regeneration methods. Moreover, knowledge of gene function and genomic information in target crop species and genotypes is a prerequisite for the application of gene editing. In this respect the developments in next generation sequencing enabling whole genome sequencing as well as targeted sequencing are supporting the technology deployment of gene editing. This review will explore the possibilities and challenges of applying gene editing in ornamental species. It will also provide examples of gene editing applications in some ornamental crops and discuss the opportunities offered by this technique for breeding new ornamental cultivars with improved resistance to pests and diseases.