Axillary buds of in vitro microshoots were successfully frozen at –196 °C by the one-step freezing method using the protective vitrification solution 2 (PVS2). Microshoots were taken from 11 transgenic lines and three wild type lines. Influence of different explant pretreatments were analyzed from the point of their influence towards recovery after cryopreservation. It was found out that the use of axillary buds as explants after removal of the apical one increases recovery on average by 8%. The cultivation on growth medium of higher density insignificantly raises the regenerants survival rate. Pretreatment of the osmotic fluid (OF) shows the greatest influence on the survival rate. It leads to the increase in survival rate by 20%. The cryopreservation technology providing regenerants average survival rate of 83% was developed. It was based on the experimental results obtained with explant pretreatment. Incubation time in liquid nitrogen did not affect the explants survival rate after thawing. After six months cryostorage of samples their genetic variability was analyzed. Six variable simple sequence repeat (SSR) loci were used to analyze genotype variability after the freezing-thawing procedure. The microsatellite analysis showed the genetic status identity of plants after cryopreservation and of the original genotypes. The presence of the recombinant gene in the transgenic lines after cryostorage were confirmed so as the interclonal variation in the growth rate under greenhouse conditions. The developed technique is recommended for long-term storage of various breeding and genetically modified lines of aspen plants, as it provides a high percentage of explants survival with no changes in genotype.

The creation of urban agglomerations of green forest belts is one of the conditions for the sustainable development of society. The cities of forest parks' green belts help to form the ecological framework of the territories, thereby increasing the level of quality of life of the population. The data obtained allow us to substantiate the need to create a forest-park green belt for a large urban agglomeration (Voronezh city) and to identify clear criteria for the selection of sites that will be included in it. Keywords-green park belt, ecosystem functions, ecological frame sustainable development, quality of life.I.

No abstract

The creation of forest-park green belts is defined by chapter IX.1 of the Federal Law "On Environmental Protection" for the purpose of limiting mode of nature use and management and conservation of natural ecological systems. Forest-park green belts are a new form of realization of the right of urban residents to a favourable environment. In the forest-steppe zone, important bioclimatic and environmental requirements are imposed on the formation of forest-park green belts: in winter – protection from adverse winds; in summer – protection from dust storms, dry winds, from excessive insolation, fastening of slopes, ravines, soils. Forest-park green belts should carry a significant ecosystem load. The most important indicator of the successful functioning of forest-park green belt is its placement, configuration and size. It is scientifically justified to use four criteria for determining priority areas for inclusion in the forest-park green belt. The localization criterion, which is the basis for the inclusion of the site in the forest-park green belt, reflects the remoteness of the site (proximity) from the urban agglomeration. The criterion of "ecosystem load" reflects the fulfilment of the ecological functions by the site. The criterion "Site type" serves to determine the origin of the site and evaluate its distinctive features. The criterion "Existence of encumbrances" serves as an indicator of the incompatibility of the site with the goals of creating a forest-park green belt. The selection of sites for inclusion in the forest-park green belt is carried out taking into account the opinion of experts on the results of their questioning. The proposed methodical approach to identifying sites for inclusion in the forest-park green belt can be used at all levels of forest management by regional executive authorities to justify management decisions to create a "green shield" of the territories.