Interactive Effects of Drought and Saline Aerosol Stress on Morphological and Physiological Characteristics of Two Ornamental Shrub Species

Effects of drought and aerosol stresses were studied in a factorial experiment based on a Randomized Complete Design with triplicates on two ornamental shrubs. Treatments consisted of four levels of water container (40%, 30%, 20%, and 10% of water volumetric content of the substrate) and, after 30 days from experiment onset, three aerosol treatments (distilled water and 50% and 100% salt sea water concentrations). The trial was contextually replicated on two species: Callistemon citrinus (Curtis) Skeels and Viburnum tinus L. ‘Lucidum’. In both species, increasing drought stress negatively affected dry biomass, leaf area, net photosynthesis, chlorophyll a fluorescence, and relative water content. The added saline aerosol stress induced a further physiological water deficit in plants of both species, with more emphasis on Callistemon. The interaction between the two stress conditions was found to be additive for almost all the physiological parameters, resulting in enhanced damage on plants under stress combination. Total biomass, for effect of combined stresses, ranged from 120.1 to 86.4 g plant−1 in Callistemon and from 122.3 to 94.6 g plant−1 in Viburnum. The net photosynthesis in Callistemon declined by the 70% after 30 days in WC 10% and by the 45% and 53% in WC 20% and WC 10% respectively after 60 days. In Viburnum plants, since the first measurement (7 days), a decrease of net photosynthesis was observed for the more stressed treatments (WC 20% and WC 10%), by 57%. The overall data suggested that Viburnum was more tolerant compared the Callistemon under the experimental conditions studied.

SHRUBS AS AN ELEMENT OF THE PARK ENVIRONMENT

Ornamental shrubs are one of the elements of the formation of the park environment and an integral part of urban landscaping. The paper presents the results of studying the species diversity of shrubs in park plantations in the city of Voronezh. The range includes more than 30 species, decorative forms and varieties of plants. Deciduous species are predominant, while coniferous species account for not much more than 10 %. Deciduous shrubs growing in the parks of the city of Voronezh belong to 14 families. Among them, there are beautiful flowering and decorative deciduous species, as well as plants with attractive fruits. Coniferous species belong to two families-pine and cypress. The cypress family is characterized by the greatest species (form, variety) diversity. The most popular types and varieties of coniferous trees are Western thuja "Smaragd", Western thuja "Danika", Cossack juniper, Cossack juniper"Tamariscifolia". The main types of shrub plantings in park stands are hedges and row plantings. The most common hedges are made of brilliant dogwood and Wanguttaspirea. Less often, groups and tapeworms are used in park plantings. The analysis of the geographical origin of shrubs showed that the largest number of species are introduced − their participation is more than 90%, the share of local species is less than 10%.

Assortment and condition of flower beds at the Soborniy district of Dnipro city

The assortment and condition of flower beds at the Soborniy district of Dnipro city were researched. 513 flower beds were identified on the territory of 18 objects (10 streets, 4 boulevards and 4 park zones). 151 flower beds, 21 ridges, 322 containers, 5 mixborders, 7 borders, 1 rockery, 6 near-barrel tree circle decorated with flowers were identified. The total area of flower beds is 7844.3 m2, of which almost 80 % falls on flower beds, about 10 % - on ridges, other types of flower beds make up an insignificant part. The assortment of flowering plants is represented by 15 species of annuals and 33 species of perennials. The leaders in the frequency of use in flower beds among annuals can be called brilliant salvia, marigolds erect and rejected, hybrid petunia, ever-flowering begonia. Garden roses, irises, stonecrops, hosts, perennial heliopsis prevail among perennial flowers. Analysis of the flower beds condition showed that landscaping objects located on boulevards look best. More than half of them are in good condition, the rest are in satisfactory condition. Flower gardens located in parks and squares are in poor condition. Only 5,7 % of flower beds were found in good condition - mainly on the territory of Shevchenko Park. Almost 40 % of flower beds are in poor condition, often completely overgrown with weeds. The flower beds located in the highways are also in most unsatisfactory condition due to the lack of regular professional care. Marigolds, ever-flowering begonia, hybrid petunia, rock alyssum retain the best condition among annuals by the end of the season. The most decorative during the season among perennials remained various types of sedum and hosta lancifolia. It is undesirable to use plants that quickly lose their decorative effect: irises, perennial heliopsis, whitewashed cornflower. Combined flower beds look best with the involvement of annual and perennial flowering plants, as well as ornamental shrubs.

Assessment of the ecological and biological features of the development of shrub introduced species in the conditions of the Central Black Earth Region

In the course of research, the authors analyzed the results of the introduction of shrub plants of different taxonomic groups in the conditions of the Central Black Earth Region. Most of the representatives of the collections under consideration (a collection of deciduous shrubs, a collection of ornamental shrubs, a collection of coniferous shrubs) showed significant adaptive capabilities in the conditions of the region under consideration. Recommendations on the possibility of using introduced shrubs in green urban construction are given, and species and forms that are not suitable for this purpose are identified. The authors have developed a methodology for assessing the results of introduction tests of shrub plants using the example of the Central Black Earth Region, which can be used in other regions of the Russian Federation and countries of the world to conduct similar tests. This technique is quite simple, but it allows you to create a complete picture of the adaptive capabilities of introduced species, since is based on basic indicators of plant vitality (drought resistance, winter hardiness, average annual growth, observation of flowering and seed production).

Spring phenology of some ornamental species, as an indicator of temperature increase in the urban climate area

The aim of this study is to provide information on the phenology of urban spring season, of some species of ornamental trees and shrubs, in the light of climate changes occurred over the recent decades. Ten species of ornamental shrubs and trees cultivated in two areas of a town located in southwestern Romania were studied. It was found that the spring season phenology of the studied species is dependent on the climatic year, in recording differences between the number of days from November 1 and the beginning of each spring phenophase, both from one species to another and from one climatic year to another, and also from one area to another; the spring phenology starting earlier in the urban area regardless of the species and the climatic year. Higher temperatures, rising from one year to another, are speeding-up the onset and development of spring phenology, regardless of species, and the urban climate through the effect of urban heat island leads to even earlier onset of spring phenophases and shortening of the growing season, so that by phenological differences existing within the species from one climatic year to another and from one climatic zone to another, spring season phenology can be considered an indicator of temperature rise.

The Technology Of Creating Topiary Compositions With The Participation Of Ornamental Shrubs - Frame Topiary In The “Green Art” Style

To create a unique design on your sites, in parks, recreation centers, playgrounds, to create amazing entrance groups, you can use landscape figures - topiary. Using decorative figures, depending on your wishes and fantasies, you can create fabulous corners for children using the figures of fabulous characters; picturesque corners with animals, creating whole compositions: for example, using a family of bears, rabbits or roe deer, you get an exceptional view of your site, which will delight you and your guests throughout the whole season; cozy corners with benches, etc. The fashion for ornamental gardens, ponds and rocky slides will never disappear from our garden plots. Cutting shrubs and trees in the form of various shapes is now in vogue. Interest in topiary art today is starting to gain momentum more and more, exhibitions of landscape art cannot do without elements of topiary compositions.

Phenology of Pentaphylloides representatives in the Mari El Republic

Representatives of the genus Pentaphylloides are low ornamental shrubs that are valued for long abundant flowering, compact size and unpretentiousness to growing conditions. P. fruticosa is a valuable plant that has not only decorative value, but also food, medicinal, soil protection. For medicinal purposes, young flowering shoots are used, harvested during budding and flowering. The article presents the results of phenological observations in 2018-2020. The objects of the study were plants of 8 kinds of Pentaphylloides in the collection of the Botanical Garden-Institute of Volga State University of Technology (Yoshkar-Ola, Mari El Republic). The studied plants undergo most phases of seasonal development, with the exception of the mass end of shoot growth, complete lignification of shoots, mass ripening of fruits, mass leaf fall. Species and cultivars vegetated from the end of April – the beginning of May to the end of October in a short time. The vegetation period was 177-182 days. There was no significant difference in the timing of the passage of phenophases between the taxa. Plants of Р. × friedrichsenii and P. mandschurica passed most of the phenophases earlier than the average dates for the genus, and 'Goldfinger' and 'Klondike' – later. The earliest and longest flowering was characterized by P. friedrichsenii (65 d.), the latest and shortest – P. fruticosa (28 d.). All plants of P. fruticosa cultivars bloomed for a longer period than the species. After mass flowering, single flowers were observed in representatives of Pentaphyloides until mid-October.

Present and perspective cultivars of Syringa L. for greening the city of Novosibirsk

There is a need to correct a historical imbalance of ornamental shrubs and, in particular, hybrids and cultivars of genus Syringa L. in the city of Novosibirsk. Recent ambitious projects of reconstruction of the present green areas and creating the new ones have enhanced the relevance of testing the cultivars which have been conducted at the CSBG SB RAS for 35 years. In order to study further the features of biology and freeze resistance under continental climate of the south of West Siberia, CSBG’s collection was completed with 54 new samples of cultivars of genus Syringa from 5 botanical institutions and nursery gardens located in the different climatic zones.