Olga Victorovna Gladkova

Ornamental plants are widely used in horticulture and urban greening. However, when plants are used in urban greening, it is necessary to select varieties with increased tolerance to urban conditions. Copper is one of the most toxic metals to plants, so the assessment of plant resistance to copper is important for urban environments. High sensitivity of the studied plants to copper was shown. Godetia grandiflora is the most resistant to copper among the species studied. Agrostis stolonifera and Centaurea cyanus had comparable resistance to copper. The effect of copper on calli of Agrostis stolonifera was also studied.

Heavy metals and flooding are among the primary environmental factors affecting plants and microorganisms. This review separately considers the impact of heavy metal contamination of soils on microorganisms and plants, on plant and microbial biodiversity, and on plant–microorganism interactions. The use of beneficial microorganisms is considered one of the most promising methods of increasing stress tolerance since plant-associated microbes reduce metal accumulation, so the review focuses on plant–microorganism interactions and their practical application in phytoremediation. The impact of flooding as an adverse environmental factor is outlined. It has been shown that plants and bacteria under flooding conditions primarily suffer from a lack of oxygen and activation of anaerobic microflora. The combined effects of heavy metals and flooding on microorganisms and plants are also discussed. In conclusion, we summarize the combined effects of heavy metals and flooding on microorganisms and plants.

Petroleum is the most common global fossil fuel. It is a complex multi-component system mainly composed of various hydrocarbons such as alkanes, cycloalkanes, mono-, bi- and polyaromatic compounds, resins and asphaltenes. In spite of humanity’s need for petroleum, it negatively affects the environment due to its toxicity. The ecological problem is especially serious at petroleum mining sites or during petroleum transportation. Since it is not possible to replace petroleum with less toxic fuel, ways to reduce the toxic impact of petroleum hydrocarbons on the environment need to be developed. This review addresses bioremediation, a biological approach to petroleum degradation, which is mainly performed by microbes. The pathways of degradation of alkanes, alkenes and aromatic hydrocarbons are presented in detail. The effects of temperature, aeration and the presence of biogenic elements on microbial degradation of petroleum are discussed. Plant–microbe interactions involved with the bioremediation of petroleum-polluted soils are specifically addressed. The data presented in this review point to the great potential of bioremediation practices for cleaning soils of petroleum.

Cell selection was used to obtain copper-resistant plants. Developed technologies for obtaining copper-resistant plants Agrostis stolonifera and Chrysanthemum carinatum can be applied to other plant species. We obtained copper-resistant plants Festuca rubra, Brachycome iberidifolia and Linum perenne. The concept of obtaining plants resistant to copper has been developed. This concept consists of two methods. The first method is applicable when calli is highly sensitive to copper. The second method is applicable when calli are moderately sensitive to copper.

Urban sciences can be divided into three directions: Natural, Humanities and Engineering. Within the fields of urban natural and urban engineering (technical) sciences, chemical and chemico-biological research take an important place. We propose using the new term "urban chemistry" (i.e. chemistry of the urban environment) focusing on the chemical aspects of the atmosphere, water bodies, and soil of cities. Urban chemistry is interconnected with urban ecology, toxicology and urban biology, and among the biological disciplines, it is particularly related to urban botany. Urban chemistry can be seen as a separate direction of urban natural sciences, which will significantly contribute to sustainable development of cities.

Soil salinization is an important ecological problem in urban ecosystems and agro-ecosystems. Salinization has direct adverse effects on plants. Sodium chloride showed greater toxicity than bischofite to Festuca rubra. We used cell selection to increase the salt tolerance of the plants. We used sodium chloride in all stages of cultivation. We have obtained salt-tolerant Festuca rubra plants. Most Festuca rubra regenerants showed increased salt tolerance. Thus, biotechnological methods can be used to obtain lawn grasses that are resistant to salinity.

Deicing reagents are priority soil pollutants in urban ecosystems. Sodium chloride is one of the priority deicing reagents. Sodium chloride is limiting the spread of lawn grass. We first showed the possibility of using environmental biotechnology in urban greening to obtain lawn grasses tolerant of sodium chloride. We have developed a cell selection technology to obtain salt-tolerant lawn grasses. A cell selection scheme with 1% sodium chloride was used. Most of the tested regenerants were more tolerant to NaCl than original plants. The descendants of the studied regenerants demonstrated the preservation of salt resistance. Most of the descendants of the regenerants Agrostis stolonifera retained high decorative qualities under salinity conditions. The tolerance remained in the next five generations. The descendants of the most salt-tolerant clones Agrostis stolonifera demonstrated resistance to 1% sodium chloride concentration in soil. These plants can serve as the basis for the creation of new salt-tolerant varieties.