Hybridization between the locally endangered Rosa spinosissima and Rosa mollis results in the pentaploid Rosa ×sabinii in western Norway.
5 April 2016
Andersen, Heidi; Næss, Samson; Salvesen, Per HaraldRosa spinosissima is an endangered species in Norway, found only within a limited area on the southwestern coast. Presumed hybrid forms between R. spinosissima and rose species within the section Caninae have been recorded from this area since the late 19th century. Here, analyses of such hybrid plants and selected populations of the tentative parent species were performed using AFLP markers, nuclear DNA content, pollen viability and seed germination rates in addition to a more classic morphometric approach. It is established that the hybrid rose represents a single hybrid taxon, referred to as Rosa ×sabinii, formed by recurrent asymmetrical hybridization events between R. spinosissima and Rosa mollis, with the latter being the obligate ovule donor. The evidence presented does not indicate hybridization with other co-occurring rose species, or of introgression from R. mollis into R. spinosissima through backcrossing with R. ×sabinii.