Species of plants in Odesa School of Horticulture (XIX–XX centuries) (based on MSUD materials)

Landscaping of the South of Ukraine was and remains a topical issue, as it helps to solve a wide range of long-term or local problems: from economic to environmental. Both amateurs and, historically, professional institutions (nurseries, arboretums, botanical gardens, etc.) play a huge role in leveling the demand for trees, shrubs, and beautiful flowering herbs. Information about their work can be obtained from various sources, in particular — on the basis of collections of various institutions (including herbariums). Regional herbariums, due to the direction and capabilities of collectors, contain information on the appearance of new species and assortment of plants, including cultivated ones. This is important information, because a certain segment of plant species can become naturalized and spread outside the areas of cultivation, be a threat to the biodiversity of natural ecotopes. The object of research, in the Herbarium of ONU named after I.I. Mechnikov (MSUD) were herbarium sheets, the labels of which contained the inscription «School of Horticulture». It existed in Odesa for a certain time: from 1886 to (according to indirect information) 1929. There are 116 herbarium sheets for 88 species. The collectors were G.Y. Potapenko (meetings of 1917, 1923) and A. Kratinov (1919, 1920). For the authorship of G.Y. Potapenko currently has 101 ha. with 78 species from 36 families. For the species Vitis vinifera L., 20 h.a. are presented. with materials of different grades. The largest number of species and genera is found in the following families: Rosaceae, Fabaceae, Salicaceae, Aceraceae, Pinaceae. 22 families are monospecific. Among the life forms, the distribution is presented: 49 phanerophytes, 22 chamephytes, four species with transitional forms, three species — herbaceous plants. Sozophytes, with the category «exotic» are Ginkgo biloba L., Taxus baccata L. Only 19 species (24.36%) are adventive: one evapophyte, two ephemerophytes, five agrophytes, 11 ergasiophytes. According to the chronotype, chenophytes (16 species) prevail. According to the frequency of occurrence of tree–shrub species, currently in the flora of Odessa, the species are divided: 13 species occur «alone»; 14 — «occasionally», 24 — «often», 18 — «massively». There are also two herbarium sheets with an invasive species of North American origin, Acer negundo L., which has overcome the F-barrier on the territory of Ukraine. The gatherings of A. Kratinov are presented by 15 h.a. and 13 species from 11 families. Only two families (Oleaceae and Vitaceae) are represented by two species and genera each. Other families are monospecific. The spectrum of life forms includes three phanerophytes, one species with a transitional form, four chamephytes, and five types of herbaceous plants. 30.80% of species are synanthropic species: one agrophyte and evapophyte, two ergasiophytes. Herbarium materials contain valuable information, in particular for the introduction of new species in the regions, help predict aspects of the existence of new synanthropic species in the region