REGENERATION CAPACITY OF NARROW-LOCALIZED ENDEMIC SPECIES Dianthus hypanicus Andrz. in vitro

Development of effective technology of rare and endangered plant species mass reproduction in vitro is one of the urgent nowadays tasks. Diantus hypanicus Andrz. of the Caryophyllaceae Juss. family belongs to this group of plants. It is an endemic, narrow-localized species listed in the Red Book of Ukraine, the European Red List and the Annex to the Berne Convention. Prospects for the conservation of this species are associated with the study of its viability and require the development of effective reproduction methods. Aim. The purpose of the experiment was to determine the effect of different growth regulators concentrations on the D. hypanicus explants regenerative capacity during in vitro propagation. Methods. For the experiment the seed were used collected from plants of natural habitats and sown on a hormone-free nutrient medium according to the recipe of Murashige and Skoog. For 12–15 days, 4–6 cm long seedlings were obtained which were transferred to nutrient media modified with the content of growth-regulating substances: BAP 0.5–2.0 mg / l, IBA 0.01 mg / l and IAA 0.1 mg / l. Results. Initiation of adventitious buds with subsequent shoot formation was observed for 12–16 days. Each variant plants differed in number, growth activity and intensity, morphometric parameters. After 35–40 days from the explant introduction, conglomerates with well-developed leafy shoots were formed. It was found that, when modifying nutrient media with growth regulators BAP, IBA, IAA of different concentrations, D. hypanicus explants were actively undergoing regeneration processes of different intensity. Conclusions. It was proved that high ability to regenerate was the characteristic of explants cultured on a nutrient medium modified by the addition of BAP – 0.5 mg / l and IAA – 0.1 mg / l, where, on average, 18 ± 0.24 shoots of 2.42 ± 0.17 cm long were formed with a net reproduction of 19.06 ± 0.14. Shoots with 3.0–5.0 pairs of leaves that reached 3.5–6.0 cm were selected and transferred to nutrient media for rooting. Less developed shoots were planted on nutrient media for further reproduction. The next stage of the study is aimed at modifying nutrient media to achieve explants rhizogenesis and obtain a large number of plants necessary for the preservation of this endemic narrow-localized species in culture with subsequent repatriation to natural places of growth.