Polyploid wild service tree: first record of a triploid Sorbus torminalis (Rosaceae) in Britain

摘要

The genus Sorbus L. is known for its complex taxonomy involving many polyploid species. However, Sorbus torminalis (L.) Crantz has long been assumed to be uniformly diploid. An analysis of DNA content using flow cytometry revealed a triploid individual within 0.5 km of tetraploid S. devoniensis E.F. Warb. at South Tawton, Devon. The leaf morphology suggests the novel Sorbus to be a spontaneous S. torminalis triploid rather than the result of interspecific hybridisation.