ASHS 2015 Annual Conference

The Hamamelidaceae includes many popular horticultural species of woody shrubs and trees, including witch hazel (Hamamelis), winter hazel (Corylopsis), Persian ironwood (Parrotia), Fothergilla, and Loropetalum. Along with representing many ornamental species, the family also has importance to conservation. Both Loropetalum and Fothergilla include threatened or endangered species, and Parrotia has only one extant species, which could soon face endangerment. Microsatellite markers were developed from Fothergilla ×intermedia to establish loci capable of distinguishing species and cultivars, to assess genetic diversity for use by ornamental breeders, and for cross-transfer to other genera in the Hamamelidaceae. A small insert genomic library enriched for microsatellites was sequenced and 12 polymorphic microsatellite loci were characterized on accessions from five genera. The number of detected alleles per locus ranged from four to nine across the five genera included in the study. A total of 128 alleles were identified, with 90 of them unique to single genera. One locus only amplified Fothergilla, making it unique to the genus, while five loci amplified across all genera. Ten loci amplified in Corylopsis, ten in Hamamelis, nine in Parrotia, and five in Loropetalum. All 12 loci amplified in Fothergilla, as expected from the hybrid library. Shannon’s information index among markers ranged from 0.07 to 0.14. The microsatellite loci provide molecular tools to be used in evaluation of genetic diversity in natural and horticultural collections. They can also be used by ornamental plant breeders for cultivar identification and relationships for five popular genera of woody ornamental plants.