title: Towards development of new ornamental plants: status and progress in wide hybridization.
abstract: The present review provides insights into the key findings of the hybridization process, crucial factors affecting the adaptation of new technologies within wide hybridization of ornamental plants and presents perspectives of further development of this strategy. Wide hybridization is one of the oldest breeding techniques that contributed enormously to the development of modern plant cultivars. Within ornamental breeding, it represents the main source of genetic variation. During the long history of wide hybridization, a number of methods were implemented allowing the evolution from a conventional breeding tool into a modern methodology. Nowadays, the research on model plants and crop species increases our understanding of reproductive isolation among distant species and partly explains the background of the traditional approaches previously used for overcoming hybridization barriers. Characterization of parental plants and hybrids is performed using molecular and cytological techniques that strongly facilitate breeding processes. Molecular markers and sequencing technologies are used for the assessment of genetic relationships among plants, as the genetic distance is typically depicted as one of the most important factors influencing cross-compatibility in hybridization processes. Furthermore, molecular marker systems are frequently applied for verification of hybrid state of the progeny. The flow cytometry and genomic in situ hybridization are used in the assessment of hybridization partners and characterization of hybrid progeny in relation to genome stabilization as well as genome recombination and introgression. In the future, new research and technologies are likely to provide more detailed information about genes and pathways responsible for interspecific reproductive isolation. Ultimately, this knowledge will enable development of strategies for obtaining compatible lines for hybrid production. Recent development in sequencing technologies and availability of sequence data will also facilitate creation of new molecular markers that will advance marker-assisted selection in hybridization process.
authors.affiliation: Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Højbakkegård Allé 9-13, 2630, Tåstrup, Denmark. kku@plen.ku.dk.
authors.forename: Katarzyna
authors.identifier: http://orcid.org/0000-0002-6246-4797
authors.initials: K
authors.lastname: Kuligowska
authors.affiliation: Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Højbakkegård Allé 9-13, 2630, Tåstrup, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Lütken
authors.affiliation: Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Højbakkegård Allé 9-13, 2630, Tåstrup, Denmark.
authors.forename: Renate
authors.initials: R
authors.lastname: Müller
mesh_terms: D003116:Color; D035264:Flowers / Q000033:anatomy & histology / Q000235:genetics*; D006823:Hybrid Vigor / Q000235:genetics; D006824:Hybridization, Genetic; D010641:Phenotype; D010858:Pigmentation / Q000235:genetics; D000069600:Plant Breeding / Q000379:methods*; D018515:Plant Leaves / Q000033:anatomy & histology / Q000235:genetics*; D010944:Plants / Q000033:anatomy & histology / Q000235:genetics*
keywords: Flow cytometry; Genetic distance; Genomic in situ hybridization; Hybrid verification; Molecular markers; Reproductive barriers