Collection "Flora of Siberia" in the Main Botanical Garden of RAS (Russia).
The exposition "Flora of Siberia" exists since the creation of the Main Botanical Garden of Russian Academy of Sciences and covers an area of 0.045 km2. More than 100 species from 42 families and 84 genera of plants are cultivated on this territory. 65% species are successfully renewed, 80% species have been cultivated for more than 35 years. Meadow-forest plant species and species from lower mountain belt are most widely represented (31% and 23% respectively). The specifity of introduction in the climatic conditions of the centre of European Russia for many years were studied for some rare species - Melica altissima, Dasiphora fruticosa, Sibiraea laevigata etc. For a number of species from introduction populations characterised by an increase in the size of vegetative organs and an increase in the number of flowers in comparison with individuals of the same species from the natural phytocenoses of Siberia. The cultivation of new species is closely related to the problem of biological invasions. At the time ofthe foundation of the collection, in 1950s, the invasive species Sorbaria sorbifolia had not yet begun its expansion into natural phytocenoses of European Russia, and represented introductory value as a decorative species withan Asian area, but now there is strict monitoring of the number and area of the introduction population of Sorbaria sorbifolia at the exposition "Flora of Siberia". Currently, the collection is actively enriched, to include in its composition plant species from the botanical garden of the M.K. Ammosov North-Eastern Federal University in Yakutsk, seeds of several rare and protected species in many regions of Siberia were obtained: Alfredia cernua, Allium ramosum, Artemisia dracunculus, Filifolium sibiricum, Oxytropis pilosa, Draba sibirica, Silene amoena. Seeds of these species were germinated in three variants of conditions - with preliminary moist or dry cold stratification and without stratification. Our research has shown that Allium ramosum, Artemisia dracunculus and Silene amoena are most promising for seed introduction with a preliminary cold stratification.