Y. V. Zhurzha, L. A. Koldar
Dendrological park Sofiivka of National Academy of Sciences of Ukraine, Uman, Ukraine
REPRODUCTION RHAMNUS TINCTORIA WALDST. ET KIT. UNDER THE CONDITIONS IN VITRO
Among the general directions of research work of botanical institutions, there is protection of rare, endangered or those that are endangered by the flora of Ukraine. Particular attention is devoted to the development of methods of reproduction. To rare species of Ukraine's natural flora, belongs to Rhamnus tinctoria Waldst. Et Kit. (Dyer's Buckthorn) – Balkan's specie, in the Red Book of Ukraine. The aim of the research was to develop the technology of reproduction of R. tinctoria in culture in vitro using scarification and stratification of seeds. The material for research was the seeds of R. tinctoria. The experimental research have been carried out in the laboratory of the microclonal propagation of plants of the National dendrological park “Sofyivka” of the National Academy of Sciences of Ukraine. Seeds of genus Rhamnus are characterized by a state of organic rest. Therefore, before introduction into the culture in vitro, the seeds of R. tinctoria were subjected to scarification with concentrated sulfuric acid with an exposure of 15 minutes. Stratification (90 days) of untreated seeds introduced into test tubes was carried out at a temperature of +4 °C. Seeds were germinated in biological test tubes on agarized nutrient media of Murashige and Skoog (MS), using five concentrations of 6-benzylaminopurine (BAP), supplemented with vitamins and amino acids. The beginning of germination of scarified seeds was observed on days 11-15, which compared with stratification – 26-29 days and control – 47-50 days, gave the best result. After germination of seeds, the appearance of cotyledons, their deployment and growth, the appearance of the first pair of real leaves, intensive growth in height, root growth. It was found that the seed reproduction of R. tinctoria in vitro depends both on the way of overcoming organic rest, and on the quantitative content of phytohormones in nutrient media. The most effective variant was the scarification of seeds with concentrated sulfuric acid (15 min.) and a nutrient modified medium supplemented with BAP 1.0 mg/L and 1 mg/L NAA, which promoted active release of seeds from the resting state and its germination on the 11th day.
Keywords: Rhamnus tinctoria Waldst. Et Kit., seed propagation, scarify, stratification, phytohormones, in vitro