Teratogenesis of generative organs of cultivars of Rosa (Rosaceae) in the collection of the M.M. Gryshko National Botanical Garden, National Academy of Sciences of Ukraine

As a result of the observation of 80 varieties of garden roses in the collection of the M.M. Gryshko National Botanical Garden, National Academy of Sciences of Ukraine, during 2018–2022, 11 types of teratomorphs were identified and documented according to the proposed informal classification scheme. The most common anomalies of the generative organs were categorized as follows: double-flowered morphs (96.25%), petalization of stamens and sepals (55%), phyllody of flower elements (47.5%) and petal chorisis (46.25%). Such manifestations of teratogenesis as proliferation, fasciation and polymerization occur less frequently (10% and 12.5%, respectively). Syncarpy, heteromorphism and oligomerization were observed in a small number of varieties (from 1.25% to 3.75%). Sepal phyllody was found in 15 of the studied varieties, i.e. 39.47% of all records of phyllody of generative organs. The varieties 'Leda', 'Lydia', 'F.J. Grootendorst', 'The Sun and the Heart', 'Duftwolke', 'Souvenir de la Malmaison', 'Laguna' were found to be most susceptible to flower teratogenesis. The results of this research, apart from theoretical implication, can be of some interest for rose breeders.