Studies focused on maintaining high productivity and stability of artificial ecosystems that reproduce the processes of natural cenoses are relevant and interesting. It seems to be effective to include decomposers, detritivores and vegetative waste in model systems aimed at obtaining products. The use of earthworms as detritivores is promising because they utilize the organic matter as well as enrich the substrates with microflora including those with antagonistic and growth-stimulating activities. The aim of this study was to assess the prospects of preliminary bioconversion of wheat straw by basidiomycetes (Lentinus tigrinus and Pleurotus ostreatus) to increase the productivity of lettuce plants. The work was carried out in laboratory conditions with model systems consisting of a substrate (peat, cattle manure and wheat straw with and without bioconversion), earthworms (Eisenia fetida) and lettuce (Lactuca sativa var. crispa cultivar Credo). The leaf area, the weight of each plant (wet and dry), the productivity of lettuce plants, and the content of the main biogenic elements in the plant tissue and substrate were evaluated. The number and weight of adult worms at the beginning and at the end of the experiment, and the number of juvenile worms at the end of the experiment, the number of cocoons, as well as coprolite weight and yield were considered. A significant phytotoxic effect when straw was added into the substrate was found. The addition of straw processed by basidiomycetes (10%) in the substrate had a favorable effect on the earthworm population. Growing lettuce on substrates with bioconverted straw and with the earthworm introduction increases the content of major macronutrients (nitrogen, phosphorus, potassium) in plants. The introduction of earthworms contributed to a significant decrease in the phytotoxicity of substrates. Thus, it is possible to recommend the inclusion of fungiculture wastes (such as substrates after fruiting bodies obtaining) in green crop production systems together with the introduction of earthworms into substrates.

In this study, we investigated the effectiveness of silica nanoparticle (SiO2NP) suspension for pre-sowing inoculation of spring wheat seeds under soil and climatic conditions of the Western Siberia. We report that SiO2NP suspension at concentrations of 3 × 10−7

The article presents the results of a quantitative determination of the migration and distribution fluxes of plutonium radioisotopes 239 + 240Pu in coastal semiclosed marine ecosystems from a case study example of Sevastopol Bay (Black Sea) to assess the self-purification of water masses from 239 + 240Pu. The assessment was based on a study of the current (2018–2021) levels of the activity concentration of 239 + 240Pu in water, bottom sediments, perennial brown macroalgae, and benthic fish. It has been found that the main 239 + 240Pu removal flux (more than 93

Chemoecological studies were carried out in the water areas of the Kagau and Longtau rivers in the Can Gio Biosphere Reserve (Vietnam). Mass-spectrometry analysis was used to determine the concentrations of 15 microelements (heavy metals and metalloids) in water and bottom sediments. The overall pollution level in the Can Gio rivers was found to be moderate. However, the concentrations of some heavy metals in several cases exceeded the maximum permissible concentration at short-time exposure; also, the limits of safe concentrations at chronic exposure were exceeded for some elements. The concentrations of some heavy elements amount to 30 to 80% of the MPC for water bodies used for fishery. Primarily, these are copper, zinc, arsenic, vanadium, iron, and molybdenum. It was found that, according to the Regulations of Vietnam, the waters of the examined water areas showed concentrations of suspended matter in excess of the standards for category A1 sources, and the concentration of dissolved oxygen in water was below the standard. The obtained results suggest the need to monitor the chemical–ecological conditions of rivers in Can Gio as protected natural objects, which are also used to some extent for social and economic purposes.

The ability of rhizosphere bacteria to induce systemic resistance in plants has been widely described in the literature. Various products of rhizobacteria act as signalling molecules, developing stress-like reactions in the plant. At the same time, the accumulation of peroxidase and other reactive oxygen species in the cell plays a major role, and is one of the most important plant defence mechanisms in response to various stressors. Peroxidase is a polyfunctional enzyme involved in both the generation and the utilization of hydrogen peroxide, and its activity in cells is related to plant resistance to phytopathogens and adverse environmental conditions. We measured the levels of free and weakly bound guaiacol-dependent peroxidase in the roots and leaves of wheat plants both inoculated with Pseudomonas extremorientalis PhS1 and Aeromonas media GS4 and uninoculated, under conditions of high temperatures and low humidity, with and without the phytopathogen Bipolaris sorokiniana. Following inoculation, a 1.4–5.2-fold increase in the severity of plants affected with the phytopathogen was observed. Seed bacterization decreased the number of damaged plants both with and without the phytopathogen by 1.2–2.4 and 3.2–4.7 times, respectively. Seed bacterization increased peroxidase activity in leaves and roots with and without the phytopathogen. Correlation analysis showed a statistically significant (P < 0.05) relationship between the increased activity of peroxidase in wheat leaves and roots and the reduced number of affected plants. The strongest relationship was observed between the enzyme activity in wheat roots and a decrease in the disease severity with the phytopathogen.

The Sevastopol Bay located in the northern Black Sea was exposed to radioactive contamination by anthropogenic radionuclides, inter alia 238,239+240Pu, and to other types of anthropogenic load. One of them was the construction of breakwaters at the bay mouth in 1975–1986, which resulted in a change in the hydrological regime. The aim of this work was to assess the change in 238Pu and 239+240Pu sedimentation fluxes into the bottom sediments of the Sevastopol Bay mouth in the period before and after the Chernobyl NPP accident (1962–1986 and 1986–2013, respectively). Plutonium in sediments was determined by the radiochemical method, followed by measurement of the activity of radioisotopes with an alpha spectrometer. The sedimentation rate was defined by geochronological dating of sediment layers, accessing the change in 238Pu/239+240Pu activity ratio in the bottom sediment core. Then, the mass accumulation rate in the bottom sediments was calculated. As established, in the period after 1986, the mean annual sedimentation rate and mass accumulation rate in the bay mouth increased by 63 and 70 %, respectively. Assessment of 238,239+240Pu sedimentation fluxes during two research periods showed as follows: after 1986, 238Pu and 239+240Pu fluxes into the bottom sediments increased by 150 and 49 %, respectively. The increased 238Pu percentage in plutonium sedimentation flux after 1986 indicates Chernobyl origin of plutonium in the bottom sediment layers above 11 cm. In the post-Chernobyl period, the cumulative effect of an increase in 238,239+240Pu sedimentation flux into the bay mouth results both from an increase in the radioactive fallout intensity after the Chernobyl NPP accident and an effect of breakwaters on the regime of sedimentation processes in the water area (an increase in the mass accumulation rate).

Relevance of monitoring heavy metals content in the water of the Atlantic sector of the Antarctic is due to the need for a current assessment of quality of the marine environment for making responsible decisions on the conservation of marine living resources in this unique area of the World Ocean. The aim of the study was to obtain new data on levels and spatial distribution of concentrations of trace elements, mainly heavy metals, in surface water. Sampling of surface seawater was carried out during the Antarctic expedition of the 79th cruise of the RV “Akademik Mstislav Keldysh” at 21 stations in the area of the Drake Passage, the Bransfield Strait, and the Antarctic Sound, as well as in Weddell and Scotia seas. Extracting and concentrating of dissolved form of 13 trace elements (Be, Se, Sb, Tl, V, Pb, Cd, Cu, Zn, Ni, Mo, Co, and Fe) were performed using sodium diethyldithiocarbamate and carbon tetrachloride (CCl4). The elements were measured by mass spectrometry. Among all trace elements content, only Mo concentration in seawater at 9 stations, located in the Drake Passage, the Bransfield Strait, northern Weddell Sea, and off the southern coast of Tierra del Fuego Island, exceeded 1.2–2.8 times maximum permissible concentration of trace elements in fishery water bodies of the Russian Federation (MPCF). According to international regulatory legal acts, such as “Dutch sheets”, there were single cases of exceeding MPC (maximum permissible concentration under short-term exposure) for Cd and Zn, as well as exceeding TV (target value under chronic exposure) for Cu, Pb, Cd, Zn, Se, and Co at several stations. The research has shown as follows: despite limited anthropogenic pressure on this area of the Southern Ocean, in seawater of some regions of the Atlantic sector of the Antarctic, increased concentrations of several trace elements, inter alia heavy metals, are recorded. Further study of the sources of trace elements intake and the peculiarities of their distribution in seawater of the Atlantic sector of the Antarctic is required in order to account for ongoing processes, take measures for rational management, and provide ecologically acceptable use of natural resources in the Antarctic.

The article is devoted to studing of the features of sedimentation on the bottom of the northwestern shelf and western deep-water area of the Black Sea based on an analysis of our own and published data obtained by bottom sediment radioisotope geochronology. It was determined that the relationship between the mass accumulation rate and primary production was linear, due to the aggregate biogeographic, hydrological, and hydrochemical conditions. The features of bottom sediment formation in the open part of the sea were associated with the presence of hydrogen sulfide (H2S) in deep waters (deeper than 100–200 m). It was shown that 20 (on the continental slope) and 17 g/(m2 year) of particulate organic matter (in the deep-sea basin) entered from the oxygen-containing zone. In this case, the predominant fractions in bottom sediments were mineralized biogenic matter: 54 and 68.5%, respectively, in these areas. The contribution of organic, mineralized biogenic, and lithogenic sedimentary matter to the formation of the mass accumulation rate was estimated, and changes in their ratio with distance from the coast and estuaries were shown. Based on the nature of the formation of the mass accumulation rate, three groups of sea areas were identified in which the ratio of biogenic and lithogenic components in absolute masses reflected a change in their role of these components in bottom sediment formation.

Бухта Севастопольская, расположенная в северной акватории Чёрного моря, подвергалась радиоактивному загрязнению техногенными радионуклидами, включая 238,239+240Pu, и испытывала другие виды техногенной нагрузки. Одним из них явилось строительство заградительных молов на входе в бухту в 1975–1986 гг., которое привело к изменению её гидрологического режима. Целью данной работы было оценить изменение седиментационных потоков 238Pu и 239+240Pu в донные отложения устьевой части бухты Севастопольская в период до и после аварии на Чернобыльской АЭС (1962–1986 и 1986–2013 соответственно). Плутоний в осадках определяли радиохимическим методом, с последующим измерением активности радиоизотопов на альфа-спектрометре. Скорость осадконакопления определяли с помощью геохронологической датировки слоёв осадка по изменению отношения активностей 238Pu/239+240Pu в керне донных отложений. Затем рассчитывали скорость седиментации осадочного вещества в донные осадки. Установлено, что в период после 1986 г. среднегодовая скорость осадконакопления и скорость седиментации осадочного вещества в устье бухты увеличились на 63 и 70 % соответственно. Оценка седиментационных потоков 238,239+240Pu за два исследуемых периода показала, что поток 238Pu в донные отложения увеличился после 1986 г. на 150 %, а поток 239+240Pu — на 49 %. Повышенная процентная доля 238Pu в седиментационном потоке плутония после 1986 г. указывает на чернобыльское происхождение плутония в слоях донных отложений выше 11 см. Суммарный эффект увеличения седиментационных потоков 238,239+240Pu в устье бухты в постчернобыльский период обусловлен ростом интенсивности радиоактивных выпадений после аварии на ЧАЭС и влиянием гидротехнических сооружений на режим седиментационных процессов в акватории (увеличением скорости седиментации осадочного вещества).

The aim of the work is to develop the lighting mode for the cucumber photoculture. The developed lighting mode should intensify production process by optimizing spectral characteristics of the light sources used at different stages of the life cycle of the plant. The authors conducted experiments on the cultivation of cucumber culture under conditions of ecosystems of small volume with artificial illumination. As the lighting sources, LED elements with phyto-oriented spectra were used. Based on dynamics of phenological and morphometric parameters and productivity of plants, the authors concludes that pre-sowing irradiation provided positive effect on seed germination. Artificial lighting sources with additional red LEDs (625nm in the ratio 9:2) accelerated the development of the vegetative and generative systems. Illumination by white spectrum LEDs (Ra80, CCT 3000 K) contributed to improving the efficiency of photosynthesis processes extended the period of active life of the plants. The authors proposed variants of artificial lighting with the use of light sources composed of LEDs of different spectra for the effective cultivation of cucumber according to different stages of plant life cycle.

The authors of the article propose a possible algorithm for the selection of soil plots potentially suitable for growing healthy virus-free seed potatoes. As selection criteria, such microbiological characteristics of the soil are considered as the level of species diversity of the soil microbial community (determined using metagenomic analysis, as well as classical microbiological methods and the subsequent calculation of the Simpson and Berger-Parker species diversity indices), as well as the level of suppressive activity of the soil microbial community against the phytopathogenic fungus Fusarium soilani. The study of the microbiological characteristics of two arable soil plots (from different crop rotation fields and different quality of potatoes grown on them), as well as one virgin soil plot of the same type, showed that the highest level of species diversity, determined by the method of metagenomic analysis, as well as by calculating the Simpson and Berger-Parker Species Diversity indices, is characteristic of the arable soil plot with long-term application of organic fertilizers, as well as the virgin soil plot. The soil of these plots was also characterized by the highest level of the total suppressive activity of the microbial community. The second studied plot of arable soil, which had been in a state of fallow for 20 years, turned out to be less suitable for growing healthy seed potatoes, since the soil of this plot had the lowest level of species microbial diversity, as well as a low level of soil suppressive activity.

The paper shows the possibility of using Aeromonas media and Pseudomonas extremorientalis to reduce the negative effects of elevated temperatures on wheat, which was evaluated through peroxidase activation.

Evolution of the approach to assessing ionizing radiation effects on living organisms is briefly discussed in this paper. Using the example of Black Sea hydrobionts, possibility of applying the G. G. Polikarpov conceptual radiochemoecological model of chronic action zonality of ionizing irradiation dose rates in nature to assess ecological exposure of technogenic radioisotopes ionizing radiation on aquatic biota was shown. In applied hydrobiology, this model can serve as the basis for a complex approach in assessing aquatic biota ecological state and its prediction for a wide range of 239,240Pu activity concentration in seawater. The necessity of combined use of biogeochemical and equidosimetric indicators of radionuclide behavior in a water area is emphasized. In particular, for predictive dosimetric assessments, it is important to take into account quantitative characteristics of accumulative ability of Black Sea hydrobionts and a type of radioelement biogeochemical behavior, reflecting peculiarities of plutonium biogeochemical migration in a marine ecosystem.

We found that bacterization of wheat with Pseudomonas extremorientalis increases the efficiency of open photosystem II reaction centers and reduces the photosynthesis losses dissipated as heat in the presence of a phytopathogen.

Актуальность мониторинга содержания тяжёлых металлов в водах Атлантического сектора Антарктики определяется необходимостью современной оценки качества водной среды для принятия ответственных решений по сохранению морских живых ресурсов в этом уникальном регионе Мирового океана. Цель проводимых исследований — получить новые данные об уровнях и пространственном распределении концентрации микроэлементов, преимущественно тяжёлых металлов, в поверхностной воде. Отбор проб поверхностной морской воды производили в антарктической экспедиции 79-го рейса НИС «Академик Мстислав Келдыш» на 21 станции в районе проливов Дрейка, Брансфилда, Антарктика, а также в морях Уэдделла и Скотия. Экстракцию и концентрирование растворённой формы 13 микроэлементов (Be, Se, Sb, Tl, V, Pb, Cd, Cu, Zn, Ni, Mo, Co и Fe) осуществляли с помощью диэтилдитиокарбамата натрия и четырёххлористого углерода (CCl4). Измерение элементов проводили масс-спектрометрическим методом. Только для Mo на девяти станциях, расположенных в проливах Дрейка и Брансфилда, в северном районе моря Уэдделла, а также возле южного побережья острова Огненная Земля, отмечали превышение его концентрации в морской воде в 1,2–2,8 раза по отношению к ПДК микроэлементов в воде рыбохозяйственных объектов РФ (ПДКРХ). Согласно международным нормативно-правовым актам, таким как «Голландские листы», зарегистрированы единичные случаи превышения MPC (maximum permissible concentration — ПДК при краткосрочном воздействии) для Cd и Zn, а также превышение TV (target value — контрольные уровни при хроническом воздействии) для Cu, Pb, Cd, Zn, Se и Co на нескольких станциях. Исследования показали, что, несмотря на ограниченный режим антропогенной нагрузки в этом регионе Южного океана, в морской воде отдельных районов Атлантического сектора Антарктики в современный период зафиксированы повышенные концентрации некоторых микроэлементов, включая тяжёлые металлы. Необходимо дальнейшее изучение источников поступления и особенностей распределения микроэлементов в морских водах Атлантической части Антарктики для объяснения происходящих процессов, а также для принятия мер по рациональному управлению и экологически приемлемому природопользованию в Антарктическом регионе.

В настоящее время основой повышения урожайности сельскохозяйственных культур становится высокая культура земледелия, в том числе экологически безопасное применение химических удобрений и пестицидов и их замещение на биопрепараты с аналогичным спектром действия.Актуален как поиск новых видов, штаммов и изолятов бактерий-антагонистов, перспективных для использования в качестве агентов биологического контроля, так и исследование механизмов антифунгальной активности, в частности связи между способностью подавлять рост и развитие тест-объектов в модельных условиях и в агроценозе.Целью настоящей работы была оценка возможности применения бактерий, выделенных из копролитов дождевых червей, как основы биопрепарата для контроля фитопатогенных грибов -возбудителей корневых гнилей зерновых культур.Опыты проводили в 2013-2015 годах.В предварительном скрининге на наличие фунгистатической и ростостимулирующей активностей в лабораторных тестах были отобраны два штамма -Pseudomonas sp.GS4 и Pseudomonas sp.PhS1.Фунгистатический эффект определяли по способности бактерий уменьшать скорость роста грибных колоний на агаризованной питательной среде и снижать зараженность семян мягкой пшеницы (Triticum aestivum L.) сорта Иргина возбудителями инфекций в тесте с использованием рулонов стерильной фильтровальной бумаги.Контролем служили семена, замоченные в водопроводной воде.В качестве эталона использовали обработку семян разрешенным к применению на территории Российской Федерации химическим фунгицидом Дивиденд Стар КС (Dividend® Star, «Syngenta AG», Швейцария) (действующие вещества дифеноконазол -30 г/л, ципроконазол -6,3 г/л) в рекомендуемых нормах расхода.Для оценки антифунгальной активности бактерий в полевых условиях проводили учеты корневых гнилей в фазы кущения и начала цветения у растений мягкой пшеницы сорта Иргина и ячменя (Hordeum vulgare L.) сорта Ача.В лабораторном эксперименте показано статистически значимое (р < 0,05) снижение скорости роста фитопатогенных грибов Fusarium oxysporum, Bipolaris sorokiniana и Alternaria spp.(в 1,5-2,5 раза по сравнению с контролем).Выявлено уменьшение (р < 0,05) общей зараженности семян возбудителями инфекций во всех вариантах бактеризации на 53-76 % относительно контроля.Влияние бактерий в экспериментах in planta оценивалось в малых модельных системах.Полученные результаты показали статистически значимое (р < 0,05) снижение распространенности корневых гнилей при бактеризации Pseudomonas sp.GS4 на 33-37 %, Pseudomonas sp.PhS1 -на 57-60 %; индекс развития корневых гнилей снизился соответственно в 2,1-2,4 раза и в 3,3-3,5 раза.Учет численности микроорганизмов в зоне ризосферы, проведенный в фазу начала цветения зерновых в вегетационном опыте, выявил тенденцию к увеличению общей численности микроорганизмов на 19-70 % в зависимости от сельскохозяйственной культуры и варианта бактеризации.Численность фосфатмобилизующих бактерий в ризосфере пшеницы в опыте была в среднем в 5,5-7,2 раза выше, чем в контроле, в ризосфере ячменя -в 2,1-3,2 раза.Результаты учета корневых гнилей в вегетационные сезоны 2013-2015 годов показали эффективность использования как монокультур, так и комплексной бактеризации: установлено снижение индекса развития корневых гнилей пшеницы и ячменя соответственно на 6,5-57,6 и 18,6-50,0 % в зависимости от бактериальной культуры и погодных условий вегетационного периода.Наибольшую биологическую эффективность изолятов наблюдали в начале цветения растений.

Currently, crop yields can be increased by high farming standards which include environmentally friendly use of chemical fertilizers and pesticides, as well as their replacement by bioformulations having similar activity.That is why both search for new promising species, strains and isolates of bacterial antagonists for their potential use as biocontrol agents, and study of antifungal activity mechanisms, particularly the relationship between the activity in model tests and in agrocenoses, are relevant.The aim of this study was to estimate bacterial isolates from redworm coprolites as potential bioactive agents to control phytopathogenic fungi causing root rot of crops.The experiments were conducted in 2013-2015.In the preliminary laboratory screening for fungistatic and growth-promoting activity we selected two strains, Pseudomonas sp.GS4 and Pseudomonas sp.PhS1, and assessed their ability to decrease the growth rate of fungal colonies in Petri dish test on nutrient agar medium and to reduce seed infestation of soft wheat (Triticum aestivum L., Irgin cultivar) in sterile paper roll test.Seeds soaked in distilled water served as control.As a standard, we used seed treatment with a chemical fungicide Dividend® Star («Syngenta AG», Switzerland) (30 g/l difenoconazole, 6.3 g/l cyproconazole) at recommended rates.In field tests, we recorded root rots in soft wheat Irgin cultivar plants and in barley (Hordeum vulgare L.) Acha cultivar plants during tillering and beginning of blooming.The laboratory tests showed a statistically significant (р < 0.05) 1.5-2.5-folddecrease in the growth rate of phytopathogenic fungi Fusarium oxysporum, Bipolaris sorokiniana and Alternaria spp. as compared to control.In all experiments with bacterization, there was a 53-76 % decrease (р < 0.05) in total seed infestation by pathogens as compared to non-bacterized plants.The effect of the bacteria in planta was assessed in small model systems.The obtained data show a statistically significant (р < 0.05) reduction in the root rot disease incidence in bacterization with Pseudomonas sp.GS4 (by 33-37 %) and Pseudomonas sp.PhS1 (by 57-60 %).Root rot disease severity decreases 2.1-2.4-fold and 3.3-3.5-fold,respectively.In 2015, we revealed a tendency towards a 19-70 % increase in the total number of rhizosphere microorganisms at the beginning of plant blooming depending on the crop and type of bacterization.The number of phosphate-mobilizing bacteria in the rhizosphere under bacterization was, on average, 5.5-7.2-foldhigher in wheat and 2.1-3.2-foldhigher in barley than that without bacterization.Our results of root rot field study in the 2013-2015 showed the efficacy of both monocultures and complex bacterization which provided a decrease in wheat and barley root rot disease severity by 6.5-57.6 % and 18.6-50.0%, respectively, depending on the bacterial culture and the weather conditions.The maximum biological efficacy of the isolates is noted at the beginning of blooming.