The microclonal propagation protocol including initiation, propagation, rootage, and adaptation in the premises of the Botanical Garden-Institute FEB RAS was developed for the first time for a vulnerable endemic species of Primorye Territory Leontopodium palibinianum (Palibin's edelweiss). It was shown that the medium's mineral composition as well as changes in the concentration of exogenous growth regulators under the same light and temperature conditions had a substantial impact the processes

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... of growth and morphogenesis of Palibin's edelweiss. Optimal components of the microclonal propagation medium of the species were full strength Murashige and Skoog medium. Reducing in the salt amount leads to a slowdown and arrest of in vitro culture growth. Adding 2 mg/l of 6-BAP to the full strength MS medium led to mass production of plant material with the propagation factor of 9.8. It should be noted that GK3 has a positive effect on the Palibin's edelweiss culture development in vitro when used together with low concentrations of 6-BAP. When 2.4-D was used at the concentration of 1 mg/l in the medium, direct organogenesis was observed after 14 days of cultivation and further accompanied by formation of additional plant shoots. Also, addition of 1 mg/l 2iP to the MS medium had the same effect. The growth regulators caused a low propagation factor (2.4), which in turn led to production of 2–3 regenerative plants. The IBA concentration of 2 mg/l stimulated formation of the root system capable of positively withstanding acclimatization under unsterile conditions, but lowering the IBA concentration to 1 mg/L of the medium also contributed to formation of such root system, with a slower pace. During acclimatization to ex vitroconditions plant survival did not depend on the types of mixtures being used. After the acclimatization plants are stretched in height and produced additional shoots on 20–25th day.