2019 ASHS Annual Conference

Abelia is a genus of flowering woody shrubs with high ornamental and landscape potential. Only a few species and cultivars are available commercially and these are mostly sports of Abelia xgrandiflora. Despite the diversity of the genus and its 174 years of use as an ornamental plant, no genetic information is available and ploidy levels are unknown. Genome sizes were estimated in a CyFlow © Ploidy Analyser (Sysmex ^TM) with propidium iodide as a stain, using Raphanus sativus ‘Saxa’ and Abelia xgrandiflora (2n=32) as internal standards. Genome sizes were estimated in the species Abelia chinensis (three accessions), Abelia engleriana, Abelia floribunda, Abelia xgrandiflora, Abelia schumanii and Abelia serrata, the hybrids 99-1-1 (A. chinensis x A. ‘Edward Goucher’), 99-6-7 (A. ‘Edward Goucher’ x A. chinensis), and 99-6-11 (A. ‘Edward Goucher’ x A. chinensis), and the cultivars A. ‘Edward Goucher’ (A. chinensis x A. schumannii), A. ‘Francis Mason’ (sport of A. xgrandiflora) and A. ‘Raspberry Profusion’ (A. ‘Edward Goucher’ x A. chinensis). Abelia engleriana, A. ‘Edward Goucher’, A. schumannii, Abelia xgrandiflora, A. serrata, A. ‘Francis Mason’, two accessions of A. chinensis, A. ‘Raspberry Profusion’, and the hybrids 99-1-1, 99-6-7, and 99-6-11, have a genome size of approximately 0.89 to 0.93 pg of DNA. One accession of A. chinensis presented inconclusive results. Abelia floribunda has a genome size two times larger, approximately 1.92 pg of DNA, and stomata statistically larger the other Abelia species used in this study, suggesting a ploidy level greater than the other species of the study.