Exploring sustainable management by using green nano-silver to combat three post-harvest pathogenic fungi in crops.

Global crop protection and food security have become critical issues to achieve the 'Zero Hunger' goal in recent years, as significant crop damage is primarily caused by biotic factors. Applying nanoparticles in agriculture could enhance crop yield. Nano-silver, or AgNPs, have colossal importance in many fields like biomedical, agriculture, and the environment due to their antimicrobial potential. In this context, nano-silver was fabricated by Citrus medica L. (Cm) fruit juice, detected visually and by UV-Vis spectrophotometric analysis. Further, AgNPs were characterized by advanced techniques. UV-Vis spectroscopic analysis revealed absorbance spectra at around 487 nm. The zeta potential measurement value was noted as -23.7 mV. Spectral analysis by FT-IR proved the capping of the acidic groups. In contrast, the XRD analysis showed the Miller indices like the face-centered cubic (fcc) crystalline structure. NTA revealed a mean size of 35 nm for nano-silver with a 2.4 × 108 particles mL-1 concentration. TEM analysis demonstrated spherical Cm-AgNPs with 20-30 nm sizes. The focus of this research was to evaluate the antifungal activity of biogenic AgNPs against post-harvest pathogenic fungi, including Aspergillus niger, A. flavus, and Alternaria alternata. The Cm-AgNPs showed significant antifungal activity in the order of A. niger > A. flavus > A. alternata. The biogenic Cm-AgNPs can be used for the inhibition of toxigenic fungi.

Application of X-ray based modern instrumental techniques to determine the heavy metals in soils, minerals and organic media.

To evaluate the environmental concerns associated with heavy metals (HMs) during their translocations in food chains, it is crucial to gather data on the types of HMs present in soils in order to ascertain their toxicity and potential to migrate. An overview of the findings from several physical techniques used to determine and identify the HMs, sediments, individual minerals, and organic components in contaminated agricultural and industrial soils, is provided in this review article. These studies cover a variety of X-ray-based analytical techniques, including most widely used ones like X-ray absorption near edge structure, extended X-ray absorption fine structure, X-ray diffraction, and less popular ones X-ray fluorescence, etc. When compared to techniques that rely on laboratory radiation sources, synchrotron radiation offers more precision and efficiency. These methods could pinpoint the primary mechanisms influencing the soil's ability to transport contaminants and track their subsequent migration up the food chain.

Synthesis and properties of nano-cadmium oxide and its size-dependent responses by barley plant.

Present study included technological methods that made it possible to synthesize CdO nanoparticles and carry out their qualitative and quantitative diagnostics, confirming the as-prepared CdO nanoparticles (NPs) were spherical and had a size of 25 nm. Then, under the conditions of the model experiment the effect of CdO in macro and nanosized particles on absorption, transformation, and structural and functional changes occurring in cells and tissues of Hordeum vulgare L. (spring barley) during its ontogenesis was analyzed. Different analytical techniques were used to detect the transformation of CdO forms: Fourier-transform infrared spectroscopy (FTIR), Dynamic light scattering (DLS), X-ray fluorescence analysis (XRF), Scanning electron microscopy (SEM-EDXMA and TEM), X-ray diffraction (XRD), and X-ray absorption fine structure, consists of XANES - X-ray absorption near edge structure, and EXAFS - Extended X-ray absorption fine structure. Quantitative differences in the elemental chemical composition of barley root and leaf samples were observed. The predominant root uptake of Cd was revealed. CdO-NPs were found to penetrate deeply into barley plant tissues, where they accumulated and formed new mineral phases such as Cd5(PO4)3Cl and CdSO4 according to XRD analysis. The molecular-structural state of the local Cd environment in plant samples corresponding to Cd-O and Cd-Cd. The toxicity of CdO-NPs was found to significantly affect the morphology of intracellular structures are the main organelles of photosynthesis therefore, destructive changes in them obviously reduce the level of metabolic processes ensuring the growth of plants. This study is an attempt to show results how it is possible to combine some instrumental techniques to characterize and behavior of NPs in complex matrices of living organisms.

New approach to soil management focusing on soil health and air quality: one earth one life (critical review).

Soil plays a key role in ecosphere and air quality regulation. Obsolete environmental technologies lead to soil quality loss, air, water, and land systems pollution. Pedosphere and plants are intertwined with the air quality. Ionized O2 is capable to intensify atmosphere turbulence, providing particulate matter (PM2.5) coalescence and dry deposition. Addressing environmental quality, a Biogeosystem Technique (BGT*) heuristic transcendental (nonstandard and not direct imitation of nature) methodology has been developed. A BGT* main focus is an enrichment of Earth's biogeochemical cycles through land use and air cleaning. An intra-soil processing, which provides the soil multilevel architecture, is one of the BGT* ingredients. A next BGT* implementation is intra-soil pulse continuously discrete watering for optimal soil water regime and freshwater saving up to 10-20 times. The BGT* comprises intra-soil dispersed environmentally safe recycling of the PM sediments, heavy metals (HMs) and other pollutants, controlling biofilm-mediated microbial community interactions in the soil. This provides abundant biogeochemical cycle formation and better functioning of the humic substances, biological preparation, and microbial biofilms as a soil-biological starter, ensuring priority plants and trees nutrition, growth and resistance to phytopathogens. A higher underground and aboveground soil biological product increases a reversible C biological sequestration from the atmosphere. An additional light O2 ions photosynthetic production ensures a PM2.5 and PM0.1 coalescence and strengthens an intra-soil transformation of PM sediments into nutrients and improves atmosphere quality. The BGT* provides PM and HMs intra-soil passivation, increases soil biological productivity, stabilizes a climate system of the earth and promotes a green circular economy.

Speciation of macro- and nanoparticles of Cr2O3 in Hordeum vulgare L. and subsequent toxicity: A comparative study.

Chromium (Cr) is reported to be hazardous to environmental components and surrounding biota when levels exceed allowable thresholds. As Cr is extensively utilized in different industries, thereby comprehensively studied for its toxicity. Along with Cr, the applications of nano-Cr or chromium oxide nanoparticles (Cr2O3-NPs) are also expanding; however, the literature is scarce or limited on their phytotoxicity. Thereby, the current work investigated the morpho-physiological insights of macro- and nanoparticles of Cr in Hordeum vulgare L. plants. The increased accumulation and translocation of Cr under the exposure of both forms disturbed the cellular metabolism that might have inhibited germination and growth as well as interfered with the photosynthesis of plants. The overall extent of toxicity was noticeably higher under nanoparticles' exposure than macroparticles of Cr. The potential cue for such phytotoxic consequences mediated by Cr nanoparticles could be an increased bioavailability of Cr ions which was also supported by their total content, mobility, and factor toxicity index. Besides, to support further these findings, synchrotron X-ray technique was used to reliably identify Cr-containing compounds in the plant tissues. The X-ray spectra of the near spectral region and the far region of the spectrum of K-edge of Cr were obtained, and it was established that the dominant crystalline phase corresponds to Cr2O3 (eskolaite) from the recorded observations. Thus, the obtained results would allow revealing the mechanism of macro- and nanoparticles of Cr induced impacts on plant at the tissue, cellular- and sub-cellular levels.

Genotoxic and morpho-physiological responses of ZnO macro- and nano-forms in plants.

In the current study, two plants, viz., Pisum sativum L. and Hordeum vulgare L., were exposed to nano- and macro-dispersed ZnO at 1, 10, and 30 times of maximal permissible concentration (MPC). The main objective of the study is to depict and compare the genotoxicity in terms of chromosomal anomalies, cytotoxicity (i.e., mitotic index), and phytotoxicity (viz., germination, morphometry, maximal quantum yield, and chlorophyll fluorescence imaging) of macro- and nano-forms of ZnO along with their accumulation and translocation. In the case of genotoxic and cytotoxic responses, the maximal effect was observed at 30 MPC, regardless of the macro- or nano-forms of ZnO. The phytotoxic observations revealed that the treatment with macro- and nano-forms of ZnO significantly affected the germination rate, germination energy, and length of roots and shoots of H. vulgare in a dose-dependent manner. The factor toxicity index of treated soil demonstrated that toxicity soared as concentrations increased and that at 30 MPC, toxicity was average and high in macro- and nano-dispersed ZnO, respectively. Furthermore, the photosynthetic parameters were observed to be negatively affected in both treatments, but the maximal effect was observed in the case of nano-dispersed form. It was noted that the mobility of nano-dispersed ZnO in the soil was higher than macro-dispersed. The increased mobility of nano-dispersed ZnO might have boosted their accumulation and translocation that subsequently led to the oxidative stress due to the accelerated production of reactive oxygen species, thus strengthen toxicity implications in plants.

A practical evaluation on integrated role of biochar and nanomaterials in soil remediation processes.

Soil decontamination and restoration continue to be a key environmental concern around the globe. The degradation of soil resources due to the presence of potentially toxic elements (PTEs) has a substantial influence on agricultural production, food security, and human well-being, and as a result, urgent action is required. PTEs pollution is not a threat to the agroecosystems but also a serious concern to human health; thereby, it needs to be addressed timely and effectively. Hence, the development of improved and cost-effective procedures to remove PTEs from polluted soils is imperative. With this context in mind, current review is designed to distinctly envisage the PTEs removal potential by the single and binary applications of biochar (BC) and nanomaterials (NMs).2 Recently, BC, a product of high-temperature biomass pyrolysis with high specific surface area, porosity, and distinctive physical and chemical properties has become one of the most used and economic adsorbent materials. Also, biochar's application has generated interest in a variety of fields and environments as a modern approach against the era of urbanization, industrialization, and climate change. Likewise, several NMs including metals and their oxides, carbon materials, zeolites, and bimetallic-based NMs have been documented as having the potential to remediate PTEs-polluted environments. However, both techniques have their own set of advantages and disadvantages, therefore combining them can be a more effective strategy to address the growing concern over the rapid accumulation and release of PTEs into the environment.

The effect of resource-saving tillage technologies on the mobility, distribution and migration of trace elements in soil.

The influence of agricultural tillage technologies on the accumulation and distribution of trace elements in the soil is poorly studied. At the same time, intensive agriculture requires large amounts of fertilizers, growth stimulators, pesticides, and other substances, which can effect the ecological safety of the plant products and soil. This paper represents studying the effect of various agricultural techniques (including resource-saving technologies) on the mobility and profile distribution of Pb, Zn, and Cu in Haplic Chernozem. No significant influence of resource-saving tillage technologies was found on the total Pb content. Contrary, the resource-saving tillage technologies was observed to promote the growth of the total Zn and Cu content depending on the cultivation method (by 26% Zn, 34% Cu at minimal tillage, and 28% for both elements using No-till in Ap horizon). Amongst different applied agrotechnologies, there was no influence found on the profile distribution of total elements content. Only two horizons showed the total Pb content accumulation: biogenic (Ap-A) and carbonate (BC-C) horizon. In contrast, the only biogenic accumulation for Zn was determined. Copper characterizes by even distribution over the soil profile. The use of resource-saving agricultural technologies increases exchangeable fraction of Zn, Pb and Cu in soil almost by 1.5-2.0 times in the Ap horizon compared to moldboard ploughing. Despite the increase in the exchangeable fraction of Zn and Cu, this amount of micronutrients is not enough for adequate plant nutrition. The use of various agricultural technologies at Haplic Chernozem led to changes in the distribution of studied elements' exchangeable fraction over the soil profile. The study results suggested a need to increase the amount of Cu and Zn fertilizers applied to the soil with resource-saving cultivation technologies.

Advances in characterization of probiotics and challenges in industrial application.

An unbalanced diet and poor lifestyle are common reasons for numerous health complications in humans. Probiotics are known to provide substantial benefits to human health by producing several bioactive compounds, vitamins, short-chain fatty acids and short peptides. Diets that contain probiotics are limited to curd, yoghurt, kefir, kimchi, etc. However, exploring the identification of more potential probiotics and enhancing their commercial application to improve the nutritional quality would be a significant step to utilizing the maximum benefits. The complex evolution patterns among the probiotics are the hurdles in their characterization and adequate application in the industries and dairy products. This article has mainly discussed the molecular methods of characterization that are based on the analysis of ribosomal RNA, whole genome, and protein markers and profiles. It also has critically emphasized the emerging challenges in industrial applications of probiotics.

Nanobionics in Crop Production: An Emerging Approach to Modulate Plant Functionalities.

The "Zero Hunger" goal is one of the key Sustainable Development Goals (SDGs) of the United Nations. Therefore, improvements in crop production have always been a prime objective to meet the demands of an ever-growing population. In the last decade, studies have acknowledged the role of photosynthesis augmentation and enhancing nutrient use efficiency (NUE) in improving crop production. Recently, the applications of nanobionics in crop production have given hope with their lucrative properties to interact with the biological system. Nanobionics have significantly been effective in modulating the photosynthesis capacity of plants. It is documented that nanobionics could assist plants by acting as an artificial photosynthetic system to improve photosynthetic capacity, electron transfer in the photosystems, and pigment content, and enhance the absorption of light across the UV-visible spectrum. Smart nanocarriers, such as nanobionics, are capable of delivering the active ingredient nanocarrier upon receiving external stimuli. This can markedly improve NUE, reduce wastage, and improve cost effectiveness. Thus, this review emphasizes the application of nanobionics for improving crop yield by the two above-mentioned approaches. Major concerns and future prospects associated with the use of nanobionics are also deliberated concisely.

Microplastic Pollution: An Emerging Threat to Terrestrial Plants and Insights into Its Remediation Strategies.

Microplastics (MPs) are ubiquitous and constitute a global hazard to the environment because of their robustness, resilience, and long-term presence in the ecosystem. For now, the majority of research has primarily focused on marine and freshwater ecosystems, with just a small amount of attention towards the terrestrial ecosystems. Although terrestrial ecosystems are recognized as the origins and routes for MPs to reach the sea, there is a paucity of knowledge about these ecological compartments, which is necessary for conducting effective ecological risk assessments. Moreover, because of their high persistence and widespread usage in agriculture, agribusiness, and allied sectors, the presence of MPs in arable soils is undoubtedly an undeniable and severe concern. Consequently, in the recent decade, the potential risk of MPs in food production, as well as their impact on plant growth and development, has received a great deal of interest. Thus, a thorough understanding of the fate and risks MPs, as well as prospective removal procedures for safe and viable agricultural operations in real-world circumstances, are urgently needed. Therefore, the current review is proposed to highlight the potential sources and interactions of MPs with agroecosystems and plants, along with their remediation strategies.

Intra-soil waste recycling provides safety of environment.

Amelioration and remediation technology was developed for phosphogypsum utilization in Haplic Chernozem of South-European facies (Rostov Region). The technology comprises phosphogypsum dispersed application into the soil layer of 20-45 cm during intra-soil milling. In the model experiment, the phosphogypsum doses 0 (control), 10, 20, and 40 t ha-1 were studied. The Cd thermodynamic forms in soil solution were calculated via the developed mathematical chemical-thermodynamic model and program ION-3. The form of ion in soil solution (or water extract) was considered accounting the calcium-carbonate equilibrium (CCE) and association of ion pairs CaCO30; CaSO40, MgCO30, MgSO40, CaHCO3+, MgHCO3+, NaCO3-, NaSO4-, CaOH+, MgOH+. For calculation of the equilibrium of microelements concentration in soil solution ion including heavy metals (HMs), the coefficient of microelement association kas was proposed. According to calculations, Cd2+ ion in soil solution was mostly bounded to associates CdOH+, partly to associates CdCO30 and CdHCO3+. The calculated kas of Cd was 1.24 units in the control option of experiment and decreased to 0.95 units at phosphogypsum dose 40 t ha-1. The ratio of "active [Cd2+] to total Cd" reduced from 33.5% in control option to 28.0% in the option of phosphogypsum dose 40 t ha-1. The biogeochemical barrier for penetration of HMs from soil to plant roots was high after application of phosphogypsum. According to calculation by ION-3, the standard soil environmental limitations overestimate the toxicity of Cd in soil solution. New decision for intra-soil milling and simultaneous application of phosphogypsum was developed to provide the environmentally safe waste recycling.

Soil organic matter and biological activity under long-term contamination with copper.

Organic matter (OM) and enzymes activity can act as indicators of the time and level of soil contamination with heavy metal. The goal of this study is evaluation of the effect of chronic long-term soil contamination with Cu on OM and biological activity in Spolic Technosols. The monitoring plot is located in the zone of industrial wastewater storage and sludge reservoirs in the Seversky Donets River flood plain. The total amount of Cu in the investigated soils varied greatly from 52 to 437 mg/kg. The results of Cu sequential fractionation the contaminated soil have shown that the chemical fraction composition of metal changed when the soil contamination level increased. The amount of Cu compounds associated with OM and Fe and Mn oxides was also higher. Fractions of OM from the humic and fulvic acids groups were studied. Soil was subjected to extraction with cold and hot water, and the content of water-soluble OM (WSOM) was determined. An increased solubility of humic and fulvic acids as well as elevated content of cold and hot extraction WSOM was established. The cold-extracted amount of WSOM increased with an enhance in the Cu content. The long-term contamination of soil with Cu leads to an adaptation of microorganisms to this adverse environmental factor, and this adaptation is manifested in the WSOM content increase. The effect of Cu contamination on microbiological activity was assessed by plate-counting culturable microorganisms and determining urease and dehydrogenase enzymatic activity. A high level of soil contamination with Cu showed a noticeable negative effect on the number of soil bacteria; however, active and potentially active bacteria were observed even in the highly contaminated soils. The changes in soil OM and microbial communities caused by Cu pollution can lead to disruption of ecosystem functioning.

Application of XAFS and XRD methods for describing the copper and zinc adsorption characteristics in hydromorphic soils.

Modeling metal sorption in soils is of great importance to predict the fate of heavy metals and to assess the actual risk driven from pollution. The present study focuses on adsorption of HM ions on two types of hydromorphic soils, including calcaric fluvisols loamic and calcaric fluvic arenosols. The individual and competitive adsorption behaviors of Cu and Zn on soils and soil constituents are evaluated comprehensively. It is established that the sorption processes were best described with the Langmuir model. The results suggest that the calcaric fluvic arenosols are more vulnerable to heavy metal input compared to fluvisols loamic. In all cases, Cu had a higher range of values of the adsorption process parameters relative to Zn. The Zn is likely to be the most critical environmental factor in such soils since it exhibited a decreased sorption under competitive conditions. The retention mechanisms of HM in hydromorphic soils are considered. Based on theoretical calculations of ion activity in soil solutions using solubility diagrams of Cu and Zn compounds, the possibility of precipitation of Cu hydroxide and Zn carbonate in the studied soils is shown. Direct physical methods of nondestructive testing (XAFS and XRD) are applied to experimentally prove the formation of these HM compounds on the surface of montmorillonite, the dominant mineral in hydromorphic soils, and calcite. Thus, the combination of both physicochemical methods and direct physical methods can provide a large amount of real information about the mechanisms of HM retain with solid phases.

Spatial distribution of heavy metals in soils of the flood plain of the Seversky Donets River (Russia) based on geostatistical methods.

Soil contamination by heavy metals (HM) is a worldwide problem for human health. To reduce risk to human health from exposure to toxic chemicals associated with soil contamination, it is necessary to monitor and assess HM concentrations in the soil for places where the concentration exceeds the acceptable levels. Spatial patterning is a necessary tool for assessment of the exposure risk of HM contamination. Soil sampling (n = 65) was carried out in technogenically polluted soils located at Rostov oblast to study the content and spatial distribution of four HM (Cu, Zn, Pb, and Cr) in the surface layer (0-20 cm) of the impact zone of former Lake Atamanskoe (floodplain of the Seversky Donets River valley, Rostov region) with an area of 3.91 km2. Extremely high values of HM concentrations were found with the maximum values of 702 mg/kg, 72,886 mg/kg, 2300 mg/kg, 259 mg/kg for Cu, Zn, Pb, and Cr, respectively. Inverse distance-weighted (IDW) interpolation was used to prepare 3D monoelement images of HM. Lognormal kriging and indicator kriging techniques were applied to create elemental spatial distribution maps and HM probability maps. The results showed that the total content of Cu, Zn, Pb, and Cr was moderately spatially dependent (nugget-to-sill ratio ranged from 31 to 38%), whereas the contamination index Zc formed strong spatial dependence patterns (nugget-to-sill ratio ranged from 0 to 21.4%). The obtained results of this study could serve as a guide to the authorities in identifying those areas which need remediation. Moreover, this study provides a tool for assessing the hygienic situation in the vicinity of Kamensk-Shakhtinsky (Rostov region) for decision making that can help to minimize the environmental risk of technogenic soil contamination of HM.

Analysis and assessment of heavy metal contamination in the vicinity of Lake Atamanskoe (Rostov region, Russia) using multivariate statistical methods.

Assessment of spatial patterns of potentially toxic metals is one of the most urgent tasks in soil chemistry. In this study, descriptive statistics and three methods of multivariate statistical analysis, such as the hierarchical cluster analysis (HCA), correlation analysis, and conditional inference tree (CIT), were used to identify patterns and potential sources of heavy metals (Co, Ni, Cu, Cr, Pb, MnO, and Zn). The investigation was carried out on 81 sample points, using 20 testing parameters. A strong positive correlation found among Ni, Cu, Zn, and HCA results has confirmed the common origin of the elements from waste discharge. Hierarchical CA divided the 81 test sites into 5 classes based on the soil quality and HMs contamination similarity. Regression trees for Cr, Pb, Zn, and Cu were verified by the splitting factor including HMs content and soil chemistry factors. The CIT has revealed that the elements (Cr, Pb, Zn, and Cu) concentration values are split at the first level by some other metal, indicating common anthropogenic impact resulting from industrial waste discharges. The factors at the next hierarchical level of splitting, in addition to the HMs, include compounds belonging to soil chemistry variables (SiO2, Al2O3, and K2O). The CIT nonlinear regression model is in good agreement with the data: R2 values for log-transformed concentrations of Cr, Pb, Zn, and Cu are equal to 0.775; 0.774; 0.775; 0.804, respectively.

Economic Shock and Agri-Sector: Post-COVID-19 Scenario in India.

The COVID-19 pandemic had a devastating impact on the human health and global economy. The food and agriculture sectors have also felt these effects. In many countries, the measures taken to curb the spread of the virus were initiated to hinder the supply of agricultural products to markets and consumers inside and outside the borders. How this impacts the food safety, nutrition, and the livelihoods of farmers, fishermen, and others working in the food supply chain depends mainly on short-, medium-, and long-term policy responses. Epidemics pose severe challenges to the food system in the short term, but they also offer an opportunity to face challenges and accelerate the transformation of the food and agricultural sectors to increase resilience. The aim of the review was to highlight the valuable insight on the impact of COVID-19 on the Indian agricultural system and rural economy, as well as potential strategies for post-pandemic recovery.

Thermodynamic mathematical model of the Kastanozem complex and new principles of sustainable semiarid protective silviculture management.

The Kastanozem complex in the dry steppe of southern Russia underlies an artificially-constructed forest strips. Deep ploughing to a depth of 45 cm was used to process the soil prior to planting. Between 20 and 40 cm depth, soil density was high, 1.57 t m-3. Soil hardness was also high, 440 psi. Soil aggregates greater than 5 cm in size were impermeable to tree roots. The content of such aggregates was high, comprising 35%. The number of tree roots with diameters greater than 0.5 cm that cross the soil profile was as low as 0.15 to 0.3 pcs cm-2. The soil matric potential signifying water availability was low in the vegetation period -0.9 MPa to a depth of 1.0 m. According to modelling experiments, the main salt components in the soil solution drive the transfer of soil organic matter (SOM) and heavy metals (HM). The composition of the soil solution determined by the calcium carbonate equilibrium (CCE) and the association and complexation of ions. ION-3 software was used to calculate the ion equilibrium in the soil solution. Macro-ions Cа2+, Mg2+, SO42-, and CO32- partly bonded as ion pairs. Oversaturation of the soil solution with CaCO3 was calculated according to the analytical content of macro-ion, which was high up to 1000 units, and its value decreased in response to ionic strength, activity, association, complexation, and thermodynamic equilibrium of macro-ions in the soil solution. Oversaturation calculated for Salic Solonetz and Gleyic Solonetz soil solutions was small considering the SOM content. Calculations indicate the profile and lateral loss of C from the soil to the vadose zone. The content of Pb in the soil solution was calculated sirca 75%-80%. The calculated coefficient of Pb2+ association was as high as 52.0. The probability of Pb passivation by SOM in the Kastanozem complex was significant. The probability of uncontrolled transfer and accumulation of HM in the soil and vadose zone was high. Biogeosystem Technique (BGT*) transcendental methodology, an innovative methodology created for stable geomorphological system formation to achieve sustainable agriculture and silviculture, was applied. The BGT* elements were: intra-soil milling of the 30-60 cm soil layer for geophysical conditioning; intra-soil continuously-discrete pulse watering for plants and trees to improve the hydrologic regime. The BGT* methodology reduced HM mobility, controlled biodegradation, enriched nutrient biogeochemical cycling, increased C content, increased soil productivity, and reversible carbon sequester in biological form.

Nitrogen state of Haplic Chernozem of the European part of Southern Russia in the implementation of resource-saving technologies.

BACKGROUND: The prolonged use of traditional moldboard ploughing often results in soil degradation and, ultimately, has an impact on national food security. Therefore, the implementation of resource-saving technologies (minimal and No-till) is a promising approach in the development of agriculture, especially in drought regions. The present study reports the results of long-term research on the effect of various tillage methods (moldboard ploughing, minimal tillage and No-till technique) on the nitrogen content of Haplic Chernozem of the European part of Southern Russia. The revealed regularities can be used as a theoretical basis for the effective use of resource-saving technologies, including No-till, in the zone of insufficient moisture. RESULTS: Long-term (59 years) cultivation of winter wheat using traditional moldboard ploughing has decreased the soil organic material (SOM) by 35% and total nitrogen by 32% in the soil. Minimization of tillage, in contrast, recovers the nitrogen potential of the soil in winter wheat agrocenoses. There is a statistically confirmed dependence of the content of SOM and total nitrogen on the tillage method of the upper soil horizon, with no significant effect of the tillage methods on intensity ammonification and nitrification. However, the content of nitrate-nitrogen during resource-saving tillage methods (22.8-24.4 mg kg-1 ) was higher than that after ploughing (20.3 mg kg-1 ) during all the years of the study, indicating the higher content of easily mineralizable nitrogen-containing compounds in the soil after minimal tillage. CONCLUSION: The use of resource-saving tillage technologies under conditions of insufficient moisture stabilizes the nitrogen content in soil and can improve nitrogen nutrition of plants. © 2020 Society of Chemical Industry.

The influence of application of biochar and metal-tolerant bacteria in polluted soil on morpho-physiological and anatomical parameters of spring barley.

The paper presents the results of the model experiment on spring barley (Hordeum vulgare L.) grown in polluted soil. The influence of separate and combined application of wood biochar and heavy metal-tolerant bacteria on morpho-physiological, anatomical and ultrastructural parameters of H. vulgare L. has been studied. The joint application of biochar and bacteria increased the shoot length by 2.1-fold, root length by 1.7-fold, leaf length by 2.3-fold and dry weight by threefold compared to polluted variant, bringing the plant parameters to the control level. The maximal quantum yield of photosystem II decreased by 8.3% in H. vulgare L. grown in contaminated soil, whereas this decrease was less in biochar (7%), bacteria (6%) and in combined application of bacteria and biochar (5%). As for the transpiration rate, the H. vulgare L. grown in polluted soil has shown a decrease in transpiration rate by 26%. At the same time, the simultaneous application of biochar and bacteria has led to a significant improvement in the transpiration rate (14%). The H. vulgare L. also showed anatomical (integrity of epidermal, vascular bundles, parenchymal and chlorenchymal cells) and ultrastructural (chloroplasts, thylakoid system, plastoglobules, starch grains, mitochondria, peroxisomes, ribosomes, endoplasmic reticulum, vacuoles) changes, revealed by light-optical and transmission electron microscopy of leaf sections. The effects were most prominent in H. vulgare L., grown in polluted soil but gradually improved with application of biochar, bacteria and their combination. The use of biochar in combination with metal-tolerant bacteria is an efficient tool for remediation of soils, contaminated with heavy metals. The positive changes caused by the treatment can be consistently traced at all levels of plant organization.