Despite its proven high toxicity, unsymmetrical dimethylhydrazine (UDMH) continues to be used in rocket technology and some other areas of human activity. In this work, the ability of plant-bacterial consortia to reduce the genotoxicity of UDMH and its incomplete oxidation products was investigated. Genotoxicity was assessed using a specific lux-biosensor, Escherichia coli MG1655 pAlkA-lux, which emits stronger light when cellular DNA is alkylated. For microbiological biodegradation, the Bacillus subtilis KK1112 strain was isolated from the soil via a two-stage selection process for resistance to high UDMH concentrations exceeding 5000 MAC. This strain's ability to biodegrade UDMH was demonstrated, as treatment of UDMH-polluted medium with KK1112 resulted in reduced DNA alkylation. A synergistic reduction in the DNA-alkylating potency of UDMH oxidation products was studied under the combined application of bacteria KK1112 and plant seedlings: Bromus inermis Leyss, Medicago varia Mart. and Phleum pratense L. The greatest effect was achieved when bacteria were used in combination with B. inermis. KK1112 cells accelerated seedling development and mitigated UDMH-induced growth inhibition. The findings suggest that the consortium of KK1112 and B. inermis has a great potential for remediation of UDMH-polluted soils in arid climatic zones.

Urban grasslands span climates and topography in soils with variable water infiltration and drainage rates that result in occasional waterlogging stress, while data on grass species tolerance to waterlogging stress is scant. Whole plant responses to waterlogging stress among cool-season grass species were quantified in a controlled environment. The following grasses were grown in well-drained vs. waterlogged soil for 55 d: strong creeping red fescue (Festuca rubra ssp. rubra), slender creeping red fescue (F. rubra ssp. littoralis), Chewings fescue (F. rubra ssp. commutata), hard fescue (F. brevipila), tall fescue (F. arundinacea syn. Schedonorus arundinaceus), Kentucky bluegrasses (Poa pratensis), annual bluegrass (P. annua), rough bluegrass (P. trivialis), creeping bentgrass (Agrostis stolonifera), perennial ryegrass (Lolium perenne), and alkaligrass (Puccinellia distans). Five cultivars of each fine fescue (Festuca spp.) taxon were included for comparison. When grown in waterlogged soil compared to well-drained conditions, relative differences generally ranged from -3% to -26% (shoots) and -13% to -33% (roots) for creeping bentgrass, tall fescue, and Kentucky bluegrass indicating higher waterlogging stress tolerance. The relative differences ranged from -18% to -43% in shoots and -3% to -34% in roots for annual bluegrass and perennial ryegrass indicating fair performance under waterlogging stress. Fine fescues, rough bluegrass, and alkaligrass exhibited the poorest performance during waterlogging stress with plant responses ranging from -12% to -64% (shoots) and -17% to -73% (roots). Negative whole plant responses among cultivars of four fine fescue taxa were similar. The selection of grasses tolerant to waterlogging stress will be important in developing resilient landscapes.

In savanna ecosystems, the seasonal effects of nitrogen forms and availability, as well as their utilization by plants, influence the abundance and distribution of herbaceous species in grassland communities. This study examines seasonal effects on nitrogen availability and utilization by native grass species in the Cerrado, a savanna ecosystem in Brazil. Ammonium and nitrate levels in soil, nitrate acquisition and transport, and Nitrate Reductase Activity (NRA) in different plant parts during dry and wet periods were assessed. Results indicated higher soil nitrate availability during the wet period, influenced by precipitation, with leaves showing a higher nitrate content compared to roots. There was seasonal modulation in nitrate reduction, with leaves being the primary site during the dry period and roots during the wet period. The studied grass species exhibited heterogeneous responses to seasonal nitrogen availability, potentially affecting community abundance patterns. Findings suggest that edaphoclimatic seasonality plays a crucial role in nitrogen distribution and utilization capacity by grass plants in the Cerrado, contributing to the understanding of these ecosystems' ecology.

There are concerns about the negative consequences of non-native livestock grazing of sagebrush communities, especially since these communities are experiencing unpreceded threats from invasive annual grasses, altered fire regimes, and climate change. The narrative around grazing often focuses on the effects of heavy, repeated growing season use that were common historically but now are rare or localized (e.g., near water sources). At the same time, the potential for ecological benefits of strategically applied grazing is often overlooked, limiting management options that may promote desired outcomes. To improve management in the face of unprecedented threats, we synthesized the literature to investigate and identify potential ecological benefits of strategically applied livestock grazing in sagebrush communities. We found that grazing can be used to modify fine fuel characteristics in ways that decrease fire probability and severity in sagebrush communities. Pre-fire moderate grazing may be especially important because it decreases fire severity and, thereby, promotes biodiversity and reduces postfire annual grass invasion, fire-induced mortality of native bunchgrasses, and fire damage to soil biocrusts. Grazing can create and maintain fine fuel breaks to improve firefighter safety and fire suppression efficiency. Strategic grazing can also be used to promote desirable plant community composition. Grazing can be a valuable tool, that is currently underutilized, for achieving desired management outcomes in the sagebrush and likely other ecosystems. Improper grazing can generate severe negative consequences; therefore, successful application of grazing to achieve desired outcomes will require careful attention to plant community response and balancing management objectives with community constraints.

This review examines natural pests, competitors of the Heracleum sosnowsky. Special attention is paid to the role of mutualism in the invasiveness of hogweed. the parsnip yellow spot virus, larvae of the weevil ( Lixus iridis (Olivier, 1807)), agromyzid flies ( Phytomyza pastinacae (Hendel, 1923)), umbrella moth ( Epermenia chaerophyllella (Goeze, 1783)), scoops ( Dasypolia temple (Thunberg, 1792)), depressariids ( Depressaria radiella (Goeze, 1783)), celery fly ( Euleia heraclei (Linnaeus, 1758)), lamellate beetles ( Oxythyrea funesta (Poda, 1761)), caterpillars of the Kamchatka Swallowtail ( Papiliomachaon (Linnaeus, 1758)) significantly damaged Heracleum sosnowsky. Thrips vulgatissimus (Haliday, 1836) feeds on the sap, while Lixus iridis eat leaves and stems of the above mentioned hogweed. Phoma complanate (Tode) (= Calophoma complanate) is a phytopathogenic fungi that damage Heracleum sosnowsky. Powdery mildew, ascochitosis and cylindrosporosis are most common fungal diseases of the giant hogweed. Shellfish farming and livestock grazing curb the spread of hogweed. Due to the lack of competition in the environment, the importance of its artificial creation is discussed. The fast-growing perennial grasses create dense turf that prevents germinating of hogweed seeds. Poapratensis L., Alopecuruspratensis L., Bromus inermis Leyss., Festuca rubra L., Phlumpratense L., Loliumperenne L., Helianthus tuberosus L., and Galega orientalis Lam. are among them. Replacement crops, such as Picea abies (L.) Karst. and Pinus sylvestris L., can compete in vacant lots and abandoned lands. The success of the hogweed populations introduction depends on the presence of pollinators, the spread of its seeds by animals and humans; symbiosis with fungi and bacteria. The possibility of limiting the spread of hogweed through the absence of species that improve its adaptability is discussed. It was concluded that biological control agents are promising to use and additional studies is needed to reduce the number of Heracleum sosnowsky and eliminate negative consequences for the environment.

Relevance. The need to dispose ash and slag waste from CHPP-1 and CHPP-2 in Ulan-Ude, which have a negative impact on the environment. A promising way to eliminate environmental damage is the biological reclamation of ash dumps. Its result is manifested in greening dumps and reducing ash deflation. Aim. To study ash and slag wastes from thermal power plants in Ulan-Ude and establish the possibility of reclamation of ash dumps to reduce the negative impact on the environment. Objects. Ash and slag wastes from the ash dumps of CHPP-1 (ASW-1) and CHPP-2 (ASW-2) in Ulan-Ude. Methods. Chemical, X-ray phase, granulometric, microscopic methods of analysis. Results. The authors have determined chemical, mineralogical and grain compositions of ash and slag wastes from thermal power plants. It was established that they have a high content of silicon, aluminum and a low content of calcium and magnesium. Ash and slag contain vitreous, crystalline and organic components. In the waste, to a greater extent, there is a crystalline phase containing silica, mullite, hematite, magnetite and, to a lesser extent, a glass phase, represented mainly by minerals of the orthoclase group. In terms of granulometric composition, the waste from CHPP-1 is dominated by a finer fraction compared to CHPP-2. Laboratory studies of soil mixtures based on ash and slag waste and local ameliorants (sewage sludge, lignin and chicken manure) were carried out. The optimal ratio of soil components was determined, equal to 4:1:1:1. A beneficial effect of sewage sludge was revealed, as well as a negative effect of high doses of bird droppings on growth and development of plants. Pure ash and slag from CHPP-1 and CHPP-2 without introduction of ameliorants can act as an independent substrate for perennial grasses.