Mutation types and frequency in Nigella damascena L. in the М2 and M3 generation, using ethyl methanesulfonate, nitrosomethylurea and a new derivative of dimethylsulfate, DG-2

Aim. To identify mutations and evaluate the mutation frequency in Nigella damascena L. cultivars (cvs) Bereginya and Charivnytsya (M2 and M3 generation), following treatment of their seeds with ethyl methanesulfonate (EMS), nitrosomethylurea (NMU) and a new derivative of dimethyl sulfate, DG-2. Methods. Treated Nigella seeds of two cvs with the mutagens for 6 and 16 h and in concentrations of 0.01 and 0.5 % for EMS and NMU and 0.05 and 0.5 % for DG-2. Results. A wide range of mutations (59 types) was obtained, that was divided into six groups: five groups with changes in the morphological type and one group with changes in the physiological type. Among the detected mutations, there were both previously known mutations and those obtained in this culture for the first time. The high- est mutation frequency (30 %) affecting synthesis of chlorophyll and structure of stem, shoots and leaves and 20 % for physiological features, was registered for NMU at 16 h and 0.05 % in cv. Bereginya. However, this NMU concentra- tion appeared to be lethal for cv. Charivnytsya. Conclusions. The new mutagen DG-2 proved to be most effective for inducing mutations in the corolla petal color of nigella, namely 4.0 at a 0.5 % concentration of the mutagen and 16h exposure for cv. Bereginya and 4.0 % at the same concentration and exposure for cv. Charivnytsya. DG-2 caused a substantial number of mutations in all six mutation groups affecting morphological and physiological traits. The clas- sic mutagen EMS was also effective across the spectrum of mutation groups in our study; however, it caused mutations at a lower frequency. The maximum mutation frequency under influence of EMC at a concentration of 0.05 % and an exposure of 16 h in cv. Bereginya was 11.0 %, and in cv. Charivnytsya 8.0 %. For all three mutagens used, an increase in the concentration of the active substance and of exposure time led to an increase in the mutation frequency in N. damascena plants. We will select mutants with economically valuable traits, such as tall, lodging-resistant plants and early maturing ones, for further work on the development of new cultivars of N. damascena for industrial cultivation.