Aromatic and medicinal plants diversity in the Nikita Botanical Gardens.
Preservation of plant biological diversity is an integral part of the work of botanical gardens, consisting in the creation and expansion of gene pool collections of plants by methods of introduction and selection. In the period 2015-2017 in the Nikita Botanical Gardens (NBG), through expedition trips, replenishment of gene pool collections with new species and cultivars was carried out. The aim of the work is to preserve and expand the biodiversity of aromatic and medicinal plants to create a biological basis for breeding of highly productive cultivars and forms of essential oil and medicinal crops for the south of Russia. Of the natural flora and botanical gardens of central China (Beijing), the Caucasus, and the Crimea, 166 samples of 119 species of aromatic and medicinal plants from 85 genera were brought in and planted in the NBG. Habitat in the new conditions in the southern coast of the Crimea, 104 samples of 79 plant species from 62 genera and 28 families, as well as 15 cultivars of foreign breeding that is 63% of the total number of plants brought. The primary introductory study was carried out and included in the collection of 89 samples of 63 species from 52 genera belonging to 24 plant families, representing 54% of the total number of introduced species. New species for the gene pool collection of aromatic and medicinal plants of the NBG were species of the natural flora of the Caucasus and the Crimea: Helleborus caucasicus A. Br., Periplo cagraeca L., Dioscorea caucasica Lipsky, Betonica macrantha C. Koch., Phlomis tuberosa (L.) Moench., Polygonum carneum C. Koch, etc. Over the three years of operation, the species diversity of the collection was expanded by 19%, generic diversity by 47%, cultivar diversity by 23%. In 2017, a collection of aromatic and medicinal plants totaled 389 species and forms belonging to 162 genera belonging to 48 families. The collection includes 82 cultivars of aromatic and medicinal crops, 40 of which are the NBG's breeding. Among the introduced species, promising species and cultivars have been identified as sources of biologically valuable substances, as well as for introduction into the culture and in the breeding process: Dioscorea caucasica Lipsky, Saturea laxiflora K. Koch, Phlomis tuberosa (L.) Moench, Prunella grandiflora L., Prunella vulgaris L., Perovskia × hybrida Hort. cultivar 'Blue Gaz', and Rosmarinus oficinalis L.