INTRODUCTIONAL POSSIBILITIES OF WOODY PLANTS USED FOR LANDSCAPING IN CENTRAL YAKUTIA

One of the main problems of plant introduction is the preliminary selection of plant species from other climate zones, with sufficient stability in the new conditions of growth. There have been developed many methods for the selection of species. The method of climate analogues X. Myra (the international Association of genocide scholars, 1890, 1909) – one of the first introductions of plants – implied the transfer of plants to identical climatic conditions. In the United States, the dendrologist A. Render (Render, 1947) developed the introduction zonation based on one factor – absolute minimum of air temperature. Followers of the method of climate applied analogical methods with some modifications – A. Pavari (Pavari, 1916), F. Koeppen (Corep, 1923), A. Cajander (Cajander, 1924), G. T. Selyaninov (1937), E. E. Kern (1925, 1934), V. P. Alekseev (1960), I. I. Galaktionov, A. V. By (1963) and others. In the 1980s B. N. Golovkin attempted to introduce the territory of the USSR on the same principle and to evaluate the winter hardiness of woody plants on the American scale of Reader-Women (1986). The ecological-historical method by M. V. Kultiasov (1953), based on the ecological potential of plants, acquired in the course of historical evolution. According to the method of determining selection of species according to the identity of climates (Maleev, 1933; Shlykov, 1963; Vavilov, 1965), Yakutia, having no climatic analogues, is considered as an unpromising region to tap into the culture of an alien plant. The choice of sources of introductions to Yakutia with its unfavourable climate is very difficult. The Yakut Botanical Garden of Institute for Biological Problems of Cryolithozone SD RAS (IBPC SD RAS) develops theoretical and practical issues of planting and ornamental gardening in the Far North since the 1960s. It was recommended to 150 species of ornamental herbaceous annuals and perennials and 35 species of woody plants (Krotova, 1980). Nowadays, 222 species of rees and shrubs, with various geographical origins, pass the test with the introduction of culture (Petrova, Romanova and Nazarova, 2000). However, even after 50 years of preparation of areabased assortments is focused to representatives of local wild flora. According to the current data, the flora of Yakutia has 1,970 species of vascular plants, where dendroflora includes 189 species (Variety..., 2005). Yakutian tree species have one advantage – all kinds of Yakutian trees are very winter-hardy. Therefore, the duration of the selection among them for decorative qualities is reduced by eliminating the need to select frost forms. At the same time, the high polymorphism of features allows you to select the most decorative forms.


Introduction
One of the main problems of plant introduction is the preliminary selection of plant species from other climate zones, with sufficient stability in the new conditions of growth.There have been developed many methods for the selection of species.The method of climate analogues X. Myra (the international Association of genocide scholars, 1890, 1909) -one of the first introductions of plants -implied the transfer of plants to identical climatic conditions.In the United States, the dendrologist A. Render (Render, 1947) developed the introduction zonation based on one factor -absolute minimum of air temperature.Followers of the method of climate applied analogical methods with some modifications -A.Pavari (Pavari, 1916), F. Koeppen (Corep, 1923), A. Cajander (Cajander, 1924), G. T. Selyaninov (1937), E. E. Kern (1925Kern ( , 1934)), V. P. Alekseev (1960), I. I. Galaktionov, A. V.By (1963) and others.In the 1980s B. N. Golovkin attempted to introduce the territory of the USSR on the same principle and to evaluate the winter hardiness of woody plants on the American scale of Reader-Women (1986).The ecological-historical method by M. V. Kultiasov (1953), based on the ecological potential of plants, acquired in the course of historical evolution.According to the method of determining selection of species according to the identity of climates (Maleev, 1933;Shlykov, 1963;Vavilov, 1965), Yakutia, having no climatic analogues, is considered as an unpromising region to tap into the culture of an alien plant.The choice of sources of introductions to Yakutia with its unfavourable climate is very difficult.
The Yakut Botanical Garden of Institute for Biological Problems of Cryolithozone SD RAS (IBPC SD RAS) develops theoretical and practical issues of planting and ornamental gardening in the Far North since the 1960s.It was recommended to 150 species of ornamental herbaceous annuals and perennials and 35 species of woody plants (Krotova, 1980).Nowadays, 222 species of rees and shrubs, with various geographical origins, pass the test with the introduction of culture (Petrova, Romanova and Nazarova, 2000).
However, even after 50 years of preparation of areabased assortments is focused to representatives of local wild flora.According to the current data, the flora of Yakutia has 1,970 species of vascular plants, where dendroflora includes 189 species (Variety..., 2005).Yakutian tree species have one advantage -all kinds of Yakutian trees are very winter-hardy.Therefore, the duration of the selection among them for decorative qualities is reduced by eliminating the need to select frost forms.At the same time, the high polymorphism of features allows you to select the most decorative forms.YASSR, 1973;Gavrilova, 1973).Yakutia is represented by seven floristic regions.We allocated points of input materials for the introduction in central Yakutia and held their evaluation (Table 1).

Materials and Methods
The division into zones was developed in the United States Department of Agriculture (USDA), but then became universal for gardeners in other countries (Table 2).Russia also sticks to it, because many plants are exported from foreign nurseries, and we should focus on the conditions of their cultivation.The map of climatic zones based on the minimum temperature in winter is in fact a map of hardiness or hardiness of plants.The scale has 12 climatic zones (0 to 12), from northern latitudes (zero zone, the cold) to the equator.The description of winter hardiness of species of plants and new varieties is based on this scale.In Russia there are 10 hardiness zones, from zero to nine.
Winter hardiness was determined using a scale developed in the Main Botanical garden of Academy of Sciences of Russia (Lapin and Sidneva, 1973).According  IN URBAN AREAS AND LANDSCAPE to this scale, the points of stability are defined as follows: I -plants are not frosted over, II -frosting not more than 50% of the length of annual shoots, III -frosting from 50 to 100% of the length of annual shoots, IV -freeze with older shoots, V -frosting the aboveground part to the snow cover, VI -frosting the whole aboveground part, VII -the plant dies entirely.
Trulevich N. allocates 4 groups of introduction of plant resistance and gives the following justification.
I -Unstable plants.They do not undergo a complete annual cycle of development of shoots, rhythmic processes are damaged, life as year after year, often dying in the early stages of ontogenesis (obtained from a seed) or in the first years of planting (transplanted).
Their life expectancy is up to 5 years.II -weakly stable plants.Plants are one-year development cycle shoots irregularly, life as compared to the plants natural habitats weakened, the life form often varies considerably, not independently resume the pace of ontogeny often less accelerated or slowed.In the collection of live 5-10 years.III -Resistant plants.They have a full cycle of development of shoots, rhythmic processes are stable, adapted to local climatic conditions, life as high on productivity, the size of these plants meets or exceeds their natural life form is preserved, self-seeding, not form, but successfully reproduce by artificial means.Held in the collection of up to 20 years.
IV -highly resistant plants.They develop fully as the previous ones, but multiply rapidly, often form a selfseeding or able to vegetatively samboteanu, expanding footprint and stored in a collection after 20 years.
Phenological observations of woody plants were carried out according to the "Guidelines for phenological observations in the botanical gardens of the USSR ", developed in 1975 at the Main Botanical Garden of Academy of Sciences.The degree of adaptation of the form was determined as the ratio of the actual amount of points to the maximum amount of possible points.This ratio is called the adaptation coefficient and expressed by the equation: Ka = S1 / S* × 100, where Ka -adaptation coefficient; S1 -actual points sum; S* -fully adapted plants points sum.All figures are determined on 5 score-scale where the highest score means a high degree of feature.
Taxa in the rank of families and genera are given by A.L. Takhtadzhyan (1987), generic and specific names are given by S.K. Cherepanov (1995), in some cases the names are used from different reports (Trees and shrubs of the USSR, 1949USSR, -1962)).
Data on plant phenology was processed by mathematical statistics methods using the software STATGRAPHICS Plus-Printing, NIRSMAIN and EXCEL.

Results and Discussion
About 5,000 samples of seeds were tested in Central Yakutia for 40 years.The choice of plant assortment was carried out using species of both local flora and from various botanical and geographical regions of Russia.
The species of the Yakut flora make up more than 50% (94 species, about 22 families).This group includes various uses: food, medical, technical.Many types in addition to these qualities are also decorative.
One of the criteria of introductory stability of plants is the fullness of plants' phenological phases.In conditions of culture, all woody species bloom and bear fruit annually, form the seeds, and their biological productivity increases.All this testifies their high ductility and high capacity of introduction.
Comparative analysis of phenological biorhythms allowed dividing plants into groups with different rhythmotypes.The fenorhythmotype concept combines plants with similar duration and timing of the beginning and end of the growing season, and with the same direction of the main phenological shifts states: vegetation and quiet.Timing of flowering and fruiting are considered.The growing season is determined by the number of days between the dates of onset and termination of average daily temperatures above 5 °C.Species, vegetation completed before the end of the growing season, attributed to the early growing season -ending (Ee), after the end of the growing season to late (Le)-ending vegetation.
Early rhythmotype is when vegetation starts in the first half of May, with accumulation of amount of active  (Bulygin and Firsov, 1995).
In a "green building", it is important to know decorative properties of woody plants, the conditions of their maximum development.During the observation, 168 exotic species bloomed and fruited (Korobkova, Sabaraykina, Pavlova and Ushnitskaya, 2001).The investigated types are divided into three phenological groups by time and duration of flowering (Table 3).Siberian species dominate over exotic species.Their hardiness is estimated at 1.2 points (on the scale of GBS).The analysis of the causes of unsuccessful introductions showed that for berry species migrating from Siberia (Berdsk, Novosibirsk, Barnaul) and the Northern European part of Russia (Ufa, Syktyvkar, Petrozavodsk, Michurinsk), the most important is the minimum winter temperature and the amount of average daily temperatures above 10 °C.The main type of damage is freezing off.When this value is not only the extreme minimum temperatures, but also the duration of their exposure.There is repeatability of extremely cold

Table 1
Climatic characteristics of the regions under of woody plants species growing.

Table 2
Data on the winter hardiness zones of the plants Source: Hofman H.A. 1998.Raveslot "Winterhardheid van boornkwekeriioewassen" Korobkova, T.S. -Sabaraikina, S.M. | Introductional Possibilities of Woody Plants Used For Landscaping... Plants in Urban areas and landscaPe | 2018 | pp.45-50 Among the species beginning vegetation at this time, you can select a group by timing of flowering and fruiting: with early flowering and fruiting (A v E fl E fr ), with an average flowering and fruiting (A v A fl A fr ), and late flowering and fruiting (A v L fl L fr ).The types with late rhythmotype (L v ): the beginning of vegetation is observed in the third decade of May, the amount of active temperature is 284.8 degrees, for bloom is 613 ˚C for native species are not represented.The plants of the phenogroups E v E fl E e , A v E fl A e , A v A fl E e are most adapted to local climatic rhythm and therefore more perspective for introduction in Yakutia.

Table 3
Number of species with different duration of flowering E -early; L -late; A -average Korobkova, T.S. -Sabaraikina, S.M. | Introductional Possibilities of Woody Plants Used For Landscaping... Plants in Urban areas and landscaPe | 2018 | pp.45-50