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The European Commission's "Farm to Folk" strategy recommends reducing fertilizers by at least 20% by 2030. In this context, the aim of this study was to verify whether a 20 and 40% reduction of nitrogen (N) fertilization rate will be sufficient to maintain soil chemical features, fertility, and yields in monoculture maize cultivation in the no-tillage (NT) system versus the traditional plowing (PL) system. We also examined which tillage system (PL, NT) allows the reduction of fertilization while maintaining good yields of the tested soils. Two fields (10 ha each) were established for PL and NT maize cultivation, and soils (0–20 cm) were sampled twice per year—before maize sowing and after maize harvesting. A broad range of chemical and biological parameters were monitored (i.e., pH, forms of nitrogen, phosphorus and carbon, content of selected macronutrients and humic substances, and respiration activity). It was concluded that the 20% reduction in N fertilization (after 4 years of use) did not have an adverse effect on the soil's chemical and biological features, which mainly depended on the season of the year. The maize yield seemed to be higher in the PL system, which was mostly the result of the tillage system rather than the N dose. The study will be continued in the next vegetation season to further verify our findings, especially with regard to the maize tillage system and yields. [ABSTRACT FROM AUTHOR]

Simple Summary: Bottom sediments are usually classified as extreme habitats for microorganisms. They are defined as matter deposited on the bottom of water bodies through the sedimentation process. The quality of sediments is extremely important for the good environmental status of water, because they are an integral part of the surface water environment. Microorganisms living in sediments are involved in biogeochemical transformations and play a fundamental role in maintaining water purity, decomposition of organic matter, and primary production. As a rule, studies on bottom sediments focus on monitoring their chemistry and pollution, while little is known about the structure of bacterial communities inhabiting this extreme environment. In this study, Next-Generation Sequencing (NGS) was combined with the Community-Level Physiological Profiling (CLPP) technique to obtain a holistic picture of bacterial biodiversity in the bottom sediments from Cardinal Pond intended for ecological king carp farming. It was evident that the bottom sediments of the studied pond were characterized by a rich microbiota composition, whose structure and activity depended on the season, and the most extensive modifications of the biodiversity and functionality of microorganisms were noted in summer. The main goal of the study was to determine changes in the bacterial structure in bottom sediments occurring over the seasons of the year and to estimate microbial metabolic activity. Bottom sediments were collected four times in the year (spring, summer, autumn, and winter) from 10 different measurement points in Cardinal Pond (Ślesin, NW Poland). The Next-Generation Sequencing (MiSeq Illumina) and Community-Level Physiological Profiling techniques were used for identification of the bacterial diversity structure and bacterial metabolic and functional activities over the four seasons. It was evident that Proteobacteria, Acidobacteria, and Bacteroidetes were the dominant phyla, while representatives of Betaproteobacteria, Gammaproteobacteria, and Deltaproteobacteria predominated at the class level in the bottom sediments. An impact of the season on biodiversity and metabolic activity was revealed with the emphasis that the environmental conditions in summer modified the studied parameters most strongly. Carboxylic and acetic acids and carbohydrates were metabolized most frequently, whereas aerobic respiration I with the use of cytochrome C was the main pathway used by the microbiome of the studied bottom sediments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Droughts and floods are increasing worldwide. • Changes in soil moisture affect the soil microbiome. • Climate change affects the soil environment. • Changes in the soil environment affect crop production. • Drought and floods have a negative impact on agriculture. Climate change is progressing and is already visible to the naked eye around the world. Hydrological events associated with climate change, i.e. floods and droughts, have reached extreme levels in recent years. Researchers warn that these phenomena will continue to intensify. According to recent reports, the number of extreme weather events, including hydrological phenomena, has increased by 60% in Europe over the last three decades. Both water shortages and water surpluses affect the soil environment and its functions. This in turn has a direct impact on crops and agriculture. For example, in the US alone, droughts and floods were responsible for more than 70% of the decline in cereal yields in 2011 alone. However, the soil environment is a complex ecosystem that is not yet fully understood, making it difficult to predict the impact of climate change on its quality and functioning. In this paper, we discuss the effects of floods and droughts on the soil microbiome and the implications of these changes for agriculture. We suggest that changes in soil moisture are an important factor affecting crop growth and yield, which is of great importance for global food security. [ABSTRACT FROM AUTHOR]

Methanotrophic bacteria are able to use methane (CH4) as a sole carbon and energy source. Photochemical oxidation of methane takes place in the stratosphere, whereas in the troposphere, this process is carried out by methanotrophic bacteria. On the one hand, it is known that the efficiency of biological CH4 oxidation is dependent on the mode of land use but, on the other hand, the knowledge of this impact on methanotrophic activity (MTA) is still limited. Thus, the aim of the study was to determine the CH4 oxidation ability of methanotrophic bacteria inhabiting selected arable and no-tillage soils from the Lublin region (Albic Luvisol, Brunic Arenosol, Haplic Chernozem, Calcaric Cambisol) and to identify bacteria involved in this process. MTA was determined based on incubation of soils in air with addition of methane at the concentrations of 0.002, 0.5, 1, 5, and 10%. The experiment was conducted in a temperature range of 10–30 °C. Methanotrophs in soils were identified by next-generation sequencing (NGS). MTA was confirmed in all investigated soils (in the entire range of the tested methane concentrations and temperatures, except for the arable Albic Luvisol). Importantly, the MTA values in the no-tillage soil were nearly two-fold higher than in the cultivated soils. Statistical analysis indicated a significant influence of land use, type of soil, temperature, and especially methane concentration (p < 0.05) on MTA. Metagenomic analysis confirmed the presence of methanotrophs from the genus Methylocystis (Alphaproteobacteria) in the studied soils (except for the arable Albic Luvisol). Our results also proved the ability of methanotrophic bacteria to oxidize methane although they constituted only up to 0.1% of the total bacterial community. [ABSTRACT FROM AUTHOR]

The main goal of the study was to determine new metagenomic indicators demonstrating sensitivity to soil fatigue as an effect of long-term agricultural use as well as new metagenomic indicators demonstrating bacterial resistance to human agricultural activity. Thirty-one soil samples (agriculturally exploited soil and wastelands – serving as controls) were taken for the study, in the south-eastern part of Poland. For determination of biodiversity, next generation sequencing of the 16S rRNA metagenomic amplicons were used with the Ion Torrent™ technology. Bacterial sequences were clustered into operational taxonomic units (OTUs) based on a 99% similarity threshold. The correlation matrix was constructed to assess the relationships between bacterial families and genera and the environmental data. In the studied soils, 118 families and 305 genera were identified. Among them, 10 families were recommended as sensitive indicators of soil fatigue: Sphingomonadaceae  >  Chitinophagaceae  >  Flavobacteriaceae  >  Oxalobacteraceae  >  Acetobacteraceae  >  Myxococcaceae  >  Comamonadaceae  >  Pseudomonadaceae  >  Burkholderiaceae  >  Rhodanobacteraceae . Analogically, 8 bacterial genera sensitive to agricultural practices were found: Pelomonas  >  Ramlibacter  >  Flavobacterium  >  Rhizobacter  >  Steroidobacter  >  Cellvibrio  >  Halliangium  >  Pseudomonas . Their sensitivity was confirmed by a decrease in the number of OTUs in the agricultural soils, in comparison to the wastelands. In contrast, 5 bacterial genera that should be considered as indicators of resistance to agricultural land use were proposed: Nitrosospira  >  Rhodanobacter  >  Aquicella  >  Burkholderia  >  Mucilaginibacter . Statistical tests demonstrated that the most important factors for the abundances of bacterial families and genera included soil acidity (pH), easily degradable carbon (EDC), total carbon (TC), nitrite nitrogen (N-NO 2 ), magnesium (Mg) and calcium (Ca) content, and soil moisture. [ABSTRACT FROM AUTHOR]

The effect of arable soil was quantified against non-cultivated soil on easily degradable carbon and other selected microbiological factors, i.e. soil microbial biomass, respiration activity, and dehydrogenase activity. The intent was to ascertain whether easily degradable carbo can be useful as a sensitive indicator of both soil biological degradation and microbial hotspots indication. As a result, it was found that soil respiration activity was significantly higher (p <0.0001) in all controls, ranging between 30-60 vs. 11.5-23.7 µmol CO2 kg d.m.-1 h-1 for the arable soils. Dehydrogenase activity was significantly lower in the arable soil (down to 35-40% of the control values, p <0.001) varying depending on the soil type. The microbial biomass was also significantly higher at the non-cultivated soil (512-2807 vs. 416-1429 µg g-1 d.m., p <0.001), while easily degradable carbon ranged between 620-1209 mg kg-1 non-cultivated soil and 497-877 mg kg-1 arable soil (p <0.0001). It was demonstrated that agricultural practices affected soil properties by significantly reducing the levels of the studied parameters in relation to the control soils. The significant correlations of easily degradable carbon-respiration activity (ρ = 0.77*), easily degradable carbon-dehydrogenase activity (ρ = 0.42*), and easily degradable carbon-microbial biomass (ρ = 0.53*) reveal that easily degradable carbon is a novel, suitable factor indicative of soil biological degradation. It, therefore, could be used for evaluating the degree of soil degradation and for choosing a proper management procedure. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the Bacteroidetes community structure in arable soils versus wastelands in order to assess their sensitivity to agricultural soil usage. Twelve arable soils (A) and the same number of wastelands, serving as controls (C), were grouped on the basis of the soil origin as: autogenic (AG) − formed from loess material, represented by Albic Luvisols , Haplic Luvisols , and Brunic Arenosols , hydrogenic (HG) − formed under the influence of stagnant water, represented by Haplic Chernozem , Mollic Gleysol , and Gleyic Umbrisol and lithogenic (LG) − formed from limestone, represented by Calcaric Cambisols . Additionally, the soils were classified into orders ( Luvisols , Arenosols , Chernozems , Cambisols ) according to the WRB classification rules. Statistical analyses were performed to gain the knowledge about soil chemical factors directly affecting the operational taxonomic units (OTUs) of Bacteroidetes in the soil environment. The composition of Bacteroidetes was analysed with the next generation sequencing Ion Torrent™ technology. The sequences were clustered into OTUs based on a 99% similarity threshold. An average of 2516 OTUs belonging to Bacteroidetes per C soil and 1568 OTUs per A soils were evidenced. It was found that Flavobacterium was the dominant genus in both C and A soils; however, its numbers significantly decreased in A soils, which proves its sensitivity to agricultural practices. Pedobacter and Mucilaginibacter were subdominants. Our results emphasised that, besides agricultural practices, soil genesis is an essential factor for the abundance of Bacteroidetes . They were found to prefer colonising the non-cultivated AG and HG soils rather than the LG soils. Importantly, the sensitivity to agricultural soil usage was similar irrespective of the soil classification system (genesis or orders), as reduction of Bacteroidetes OTUs in arable soils was revealed in both cases. Therefore, we recommend the Bacteroidetes phylum a sensitive biological indicator of agricultural soil usage. [ABSTRACT FROM AUTHOR]

The aim of the study was to examine the differences in microbial community structure as a result of agricultural practices. Sixteen samples of cultivated and the same number of non-cultivated soils were selected. Gel bands were identified using the GelCompar software to create the presence-absence matrix, where each band represented a bacterial operational taxonomic unit. The data were used for principal-component analysis and additionally, the Shannon- Weaver index of general diversity, Simpson index of dominance and Simpson index of diversity were calculated. Denaturing gradient gel electrophoresis profiles clearly indicated differentiation of tested samples into two clusters: cultivated and non-cultivated soils. Greater numbers of dominant operational taxonomic units (65) in non-cultivated soils were noted compared to cultivated soils (47 operational taxonomic units). This implies that there was a reduction of dominant bacterial operational taxonomic units by nearly 30% in cultivated soils. Simpson dominance index expressing the number of species weighted by their abundance amounted to 1.22 in cultivated soils, whereas a 3-fold higher value (3.38) was observed in non-cultivated soils. Land-use practices seemed to be a important factors affected on biodiversity, because more than soil type determined the clustering into groups. [ABSTRACT FROM AUTHOR]

The main goal of the study was to determine the diversity of the potential nitrogen-fixing (PNF) bacteria inhabiting agricultural (A) soils versus wastelands serving as controls (C). The soils were classified into three groups based on the formation process: autogenic soils ( Albic Luvisols, Brunic Arenosols, Haplic Phaeozem) formed on loess material, hydrogenic soils ( Mollic Gleysols, Eutric Fluvisol, Eutric Histosol) formed under the effect of stagnant water and lithogenic soils ( Rendzina Leptosols) formed on limestone. In order to determine the preferable conditions for PNF bacteria, the relationships between the soil chemical features and bacterial operational taxonomic units (OTUs) were tested. Additionally, the nitrogen content and fertilisation requirement of the lithogenic (LG), autogenic (AG) and hydrogenic (HG) soils were discussed. The composition of the bacterial communities was analysed with the next-generation sequencing (NGS) by the Ion Torrent™ technology. The sequences were clustered into OTU based on a 99 % similarity threshold. The arable soils tested were distinctly dominated by β- Proteobacteria representatives of PNF bacteria belonging to the genus Burkholderia. Bacteria from the α- Proteobacteria class and Devosia genus were subdominants. A free-living Cyanobacteria population dominated in A rather than in C soils. We have found that both soil agricultural management and soil formation processes are the most conducive factors for PNF bacteria, as a majority of these microorganisms inhabit the AG group of soils, whilst the LG soils with the lowest abundance of PNF bacteria revealed the need for additional mineral fertilisation. Our studies have also indicated that there are close relationships between soil classification with respect to soil formation processes and PNF bacteria preference for occupation of soil niches. [ABSTRACT FROM AUTHOR]

The aim of the study was to demonstrate the impact of soil agricultural usage on the abundance of ammonifying bacteria (AB) and their activity, expressed as arginine ammonification (AA). Five agriculturally exploited types of soils (FAO): Haplic Luvisol, Brunic Arenosol, Mollic Gleysol, Eutric Fluvisol, and Rendzina Leptosol were studied. The controls were non-agricultural soils of the same type located in close proximity to agricultural sites. The tested soils varied in terms of pH (4.18-7.08), total carbon (8.39-34.90 g kg), easily degradable carbon content (0.46-1.11 g kg), moisture (5.20-13.50 %), and nitrogen forms (mg kg): 1.68-27.17, 0.036-0.862, 0.012-3.389 for nitrate nitrogen, nitrite nitrogen, and ammonia nitrogen, respectively. The AB abundance in agricultural soils ranged from 1.1 to 6.4 × 10 cfu g, while in the controls it was significantly higher-from 2.0 to 110 × 10 cfu g of soil. Also, AA in the controls was three-times higher than in the agricultural soils. Strong associations between AA and the abundance of AB in the control (r = 0.954***) and agricultural soils (r = 0.833***) were proved. In the agricultural soils, the AB abundance and AA were influenced by pH (r = 0.746*** and r = 0.520***) and carbon content (r = 0.488*** and r = 0.391***). The AB abundance was also affected by easily degradable carbon (r = 0.517**) and nitrite nitrogen (r = 0.376*), whilst ammonium nitrogen influenced AA (r = 0.451*). Our results indicate that the abundance of AB and AA may be good indicators of soil biological conditions. [ABSTRACT FROM AUTHOR]

The aim of our study was to analyze the impact of soil agriculture management on bacterial abundance (expressed as total microorganism count plus copiotrophic and oligotrophic bacteria numbers) and soil dehydrogenase activity. Four different soil units agriculturally exploited (under oat-type crops) and the same number of control soils not agriculturally used were taken for study in April 2014 from the surface layer (0-20 cm). Under laboratory conditions the soils were subjected to analysis of: pH, total carbon, total microbial counts, copiotrophic and oligotrophic bacteria numbers, and dehydrogenase activity. The first consequences of agricultural practices were a decrease of pH toward acidic conditions and impoverishment of total carbon. Secondly, it was demonstrated that agricultural soil usage in relation to control sites affected biological properties by decreasing total microbial counts (by 20-75%), copio- and oligotrophic bacteria abundance (by 15-33%), and dehydrogenase activity (by 25-71). The ratio of oligotrophic to copiotrophic bacteria (O:C), being an indicator of soil biological balance, ranged 0.81-1.53 and 1.02-2.40 for arable and control soils, respectively. Lower values of biological factors observed in agricultural soils clearly indicated a progressive reduction of bacterial abundances and metabolic activities. [ABSTRACT FROM AUTHOR]

The choice of appropriate agricultural practices has a significant impact on soil quality, crop productivity, or soil microbial community. Ten representative soil samples were collected in Wierzchucin Królewski (Kujawsko-Pomorskie Province, NW Poland), an agricultural area belonging to the Potulicka Foundation Group. The cropping systems included a maize monoculture grown continuously for over 30 years and an intercropping mixture (Gorzow mixture) applied in 2020. The study aimed to determine the effect of the intercropping system on the quality and biodiversity of the studied soils and to identify bacterial indicators of sensitivity and resistance to long-term maize monoculture. Therefore, in this study, the impact of the intercrop mixture application on the chemical and biological soil properties and on the diversity of the bacterial community was evaluated by amplifying the 16S rRNA gene sequences and indicators of sensitivity and resistance to long-term maize monoculture were recommended. The results showed that intercropping had a positive effect on soil features and increased the richness and diversity of soil bacteria at the taxonomic level of genera compared to the maize monoculture. Massilia and Haliangium were proposed to be bacterial indicators of sensitivity, while Sphingomonas was recommended to be an indicator of resistance to long-term maize monoculture. Overall, our results evidenced that using an intercropping system may be a sustainable agricultural practice in this area and in north-western Poland. [ABSTRACT FROM AUTHOR]

The aim of our study was to identify the methanotrophic group of bacteria inhabiting coal mine rocks at the Jastrzebie-Moszczenica (Jas-Mos) coal mine, by application of molecular techniques: polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH). In the first stage of the experiment, methanotrophic activity (AM) of the rock material at different temperatures (20 and 30ºC) and methane (CH4) concentrations (1, 5, 10, 20%) was determined. AM noted both in 20 and 30ºC reached a similar level equaling c.a. 0.2 µM CH4g-1day-1. The PCR reactions were performed using primers specific for pmoA gene (encoding a key subunit of particulate methane monooxygenase) -- A189f and mb661, whereas FISH was realized with Mg705, Mg84 (Type I of methanotrophs), and Ma450 (Type II of methanotrophs) probes. Sequence analysis of pmoA gene demonstrated that microorganisms, being present in the investigated rocks material were similar with 95-100% identity to the following methanotrophs genera: Methylosinus, Methylobacter, Methylocystis. Concentrations of CH4 between 1-10% did not affect on bacterial variability, but in combination with 20% of CH4, significant dominance of methanotrophic bacteria Type I was stated. [ABSTRACT FROM AUTHOR]

The aim of our study was to analyze the impact of such soil physical parameters as water potential (pF), microdiffusion of oxygen (ODR), redox potential (Eh), and air porosity (Eg) on respiration activity (RA), defined as CO2 evolution after a 10-day soil incubation at 20°C. Moisture content was determined for a range of pF values (0, 1.5, 2.2, 2.7, and 3.2) that corresponded to water availability for usability by microorganisms and plant roots. Selected soil samples were extracted from the following soils layers: surface (0-30 cm), sub- surface (30-60 cm), and subsoil (60-100 cm), and were classified (FAO) as Orthic Podzol, Eutric Histosol, and Haplic Phaeozem. ODR, Eh, and Eg increased with higher soil water tension, but generally a high variability of a examined factors was observed. Respiration processes in the surface layers were the most intensive (71.5- 91.2 mg CO2 kg-1 d-1), whereas those in the subsurface and the subsoil samples were reduced by 65-98% to the level 1.6-19.2 mg CO2 kg-1 d-1 . Our results revealed significant (p<0.001) relationships between soil RA and pF, ODR, and Eh as Eg level. However, correlation coefficients (r) varied as they were indirectly dependent on soil type and depth. [ABSTRACT FROM AUTHOR]

This paper analyzes the effects of soil reoxidation, expressed in terms of water potential (pF), air porosity (Eg) and oxygen availability (ODR), on soil dehydrogenase activity (DHA). Investigated soil samples were collected from the surface layer (0-20 cm) and subsoil (50-60 cm) of Rendzina Leptosols, Eutric Histosol and Eutric Fluvisol soils. All the examined factors varied widely in the tested material - DHA decreased whereas ODR and Eg increased with higher soil water tension. A close relationship, described by significant negative correlations between oxygenation indicators (pF, ODR, Eg) and DHA, was stated. To sum up the foregoing observations, we confirmed that dehydrogenases are sensitive enzymes, indirectly dependent on soil aeration status. [ABSTRACT FROM AUTHOR]

Abstract: One of the ways of polymer waste management is its chemical modification. Waste polystyrene foam (EPS) and virgin polystyrene (VPS) as a reference material were converted into polymeric flocculants by chemical reactions. Poly(styrene sulphonate) acids (EPSS and VPSS) were obtained from EPS and VPS during the sulphonation process with sulphuric acid as the sulphonating agent and Ag2SO4 as the catalyst. Products were precipitated in the form of sodium salt (NaEPSS, NaVPSS) in the reaction with Na2CO3. The influence of temperature and the time of reaction on the properties of the products were studied. Products with determined molecular weight and number of sulphonic group per monomer units were divided into several fractions by fractional precipitation with 0.5M aqueous NaOH as the solvent and 2-propanol as the precipitant. The products were successfully used as flocculants in the treatment of the waste water discharge model colloid system, iron (III) hydroxide, which is comparable with industrial waste and water from mining companies and galvanising plants. The application of the obtained products caused a significant decrease in turbidity of the studied solutions. It was also found that the effectiveness of the flocculation depends on the number of sulphonic groups per monomer unit and the molecular weight of the polyelectrolytes. [Copyright &y& Elsevier]

The European Commission's "Farm to Folk" (F2F) strategy recommends reducing fertilizers by at least 20% by 2030. In this aspect, the main goal of our study was to verify whether a 20 and even 40% reduction in nitrogen (N) fertilization rate would be sufficient to maintain soil fertility (expressed as dehydrogenase activity—DHA, humic acid substances—HA substances, E4/E6 ratio), and yields of wheat and rapeseed cultivated in strip-till technology. Two fields (10 ha each) were established for wheat and rapeseed cultivation, and soils (0–20 cm) were sampled before sowing and after harvesting. It was found that a 20% fertilization reduction does not adversely affect the biological activity expressed by DHA. Nevertheless, the reduction in nitrogen (N) fertilizer rates led to a slight decrease in the E4/E6 ratio, which could serve as a potential indicator of fertilization reduction. DHA, E4/E6 ratio and content of HA substances were also dependent on the crop. Following harvesting, both rapeseed and wheat exhibited a positive correlation between the E4/E6 ratio and the degree of fertilization rate (FR), as well as yield. [ABSTRACT FROM AUTHOR]

Restoration of ecological functions by reclamation of post-mining areas stimulates soil-formation processes and initiates biological activity on the surfaces of disposal sites. The purpose of this investigation was to study the relationships between soil properties, microbiological activity and diversity in Technosols 45 years following land reclamation. The study area was located in the vicinity of the former Fe sulphide and uranium mine in Rudki village (Holy Cross Mts., Poland). The soils developed from tailings containing Fe sulphides (profile R1 and R2) and Fe sulphide and dolomite-bearing post-flotation sludge covered with loamy material (profile R3) were studied. Soil properties and enzyme (dehydrogenase, arylsulphatase, β-glucosidase, urease) activities, respiration activity (RA) and total microbial counts (TMC) were determined, as well as molecular analyses were performed. The most important soil properties influencing enzyme activities, RA and TMC were pH and soil salinity. Biological parameters were also dependent on TOC, TN, exchangeable K and available P contents. Enzyme activity, RA and TMC were significantly lower in strongly acidic and saline profile R1 than in profiles R2 and R3, which represent areas where land reclamation was successful. Moreover, a decrease of enzyme activities, RA and TMC were observed with increasing depth of soil profiles. The lower activity of arylsulphatase, β-glucosidase and RA in A horizon of profile R3 in comparison with similar horizon in profile R2 may reflect the pollution of R3 topsoil by trace elements. Molecular analysis revealed that Bacillus genus predominate in the studied profiles. Soil properties (particularly pH) that are a repercussion of reclamation works seem to be the main variables conditioning biodiversity at the bacterial strains and species level. The obtained results indicated that enzyme activity, RA and TMC are sensitive indicators of microbiological activity and can be a measure in the assesment of soil biological activity following land reclamation. Unlabelled Image • Biological activity and diversity can be a measure of reclamation effectiveness. • SOM is the most important factor influencing microbiological activity in Technosols. • Technosols low biological activity is an effect of low pH and high salinity. [ABSTRACT FROM AUTHOR]

The aims of the study were (1) to recognize the structure of bacteria diversity in Technosols developed from mine spoils containing iron (Fe) sulphides with the use of culture-independent technique, and (2) to determine microbial metabolic activities, in the context of their potential to be an adequate indicators of soil properties being the consequence of land reclamation. The study site was located in the vicinity of the abandoned Fe sulphide and uranium mine in Rudki village (Holy Cross Mts., Poland). Three soil profiles with different chemical properties (pH, content of carbonates, soil salinity, content of total organic carbon and total nitrogen) were studied. Biodiversity was determined with the use of meta-barcoding of 16S rRNA community profiling analysis based on the hypervariable V3-V4 region of 16S rRNA gene (MiSeq, Illumina). The catabolic fingerprinting of soil microbial communities was evaluated with the use of Biolog®EcoPlates™ System. It was evidenced that changes in microbial structure and their metabolic activity were the consequence of a combined effect of both the soil depth and soil chemical properties being the final result of reclamation process. Consequently, microbial indicators (from phyla to genera level) indirectly testifying about success or ineffectiveness of reclamation in technogenic soils were recommended. To our best knowledge, the present study is the first insight into Polish Technosols biodiversity and catabolic activity. [ABSTRACT FROM AUTHOR]

The main goal of the study was to determine the biodiversity of bacteria and their metabolic profile in the rhizosphere of four winter wheat (Triticum aestivum L.) varieties (Hondia, Nordkap, Rotax, Tytanika) cultivated in Haplic Podzol soil in a no-tillage system. Two techniques, i.e., next generation sequencing (NGS, meta-barcoding of 16S rRNA community) and community level physiological profiling (CLPP), were applied to obtain a holistic picture of biodiversity. The basic soil chemical parameters (acidity, redox potential, carbon content, forms of nitrogen, and phosphorus) were also determined. It was found that the rhizospheric microbiome (at the genus level) of cv. Hondia and Rotax were significantly different from that present in the other cultivars studied. The CLPP technique demonstrated that microbial metabolic activity depended on both the type of substrate and wheat cultivars. Carbohydrates and carboxylic acids were the most easily utilized compounds in all rhizospheric soils. The principal component analysis (PCA) evidenced that the rhizospheric soils of Rotax and Nordkap were characterized by a higher functional activity (strong correlation with the Shannon-Wiener index, the Richness index, and utilization of hydrocarbons) than those of Hondia and Tytanika. [ABSTRACT FROM AUTHOR]

The aim of the study was to determine the Actinobacteria structure in cultivated (C) versus non-cultivated (NC) soils divided into three groups (autogenic, hydrogenic, lithogenic) with consideration its formation process in order to assess the Actinobacteria sensitivity to agricultural soil use and soil genesis and to identify factors affecting their abundance. Sixteen C soil samples and sixteen NC samples serving as controls were taken for the study. Next generation sequencing (NGS) of the 16S rRNA metagenomic amplicons (Ion Torrent™ technology) and Denaturing Gradient Gel Electrophoresis (DGGE) were applied for precise determination of biodiversity. Generally, greater abundance of Actinobacteria in the NC soils relative to the C soils was found. Moreover, it was indicated that the actinobacterial diversity depended on both the soil genesis and the land use; however, this effect directly depended on the particular family and genera. Two factors: redox potential (Eh) and total carbon (TC) seemed to had a significant effect on the diversity of Actinobacteria. More precisely, Actinobacteria from the NC soils displayed a greater affinity for each other and were clearly influenced by Eh, whilst those from the C soils were mostly influenced by TC. [ABSTRACT FROM AUTHOR]

Simple Summary: The rhizosphere is the narrow region of soil that is directly influenced by root secretions and their associated microorganisms, named as the root microbiome. The rhizosphere is known as the niche most rich in microorganisms. From a microbiological point of view, the identification of these microorganisms and the discovery of the functions they perform by living, for example, in symbiosis with plants, is of interest. Consequently, this study aims to analyze the diversity of soil bacteria inhabiting the rhizospheric zone of wheat (Triticum aestivum L.), represented by four wheat cultivars (Tytanika, Nordcap, Hondia, Rotax), employing three methods of microbiome determination: (1) membership, (2) composition, and (3) functionality. Wheat cultivation in Poland is cropped on about 20% of all arable land. The studied cultivars are characterized by good yielding parameters and are highly popular for growing in Poland. A technique independent of cultivation (NGS—Next Generation Sequencing) was applied for microbial biodiversity determination, whereas for prediction of their ecological functionality, the FAPROTAX database was utilized. By performing lab analyses, we evidenced that molecular identification of the core rhizomicrobiome is particularly important for understanding the general principles regarding the selection of microorganisms around living roots and for harnessing the power of the microbiome in agricultural practice. One of the latest ecological concepts is the occurrence of a biased rhizosphere of microorganisms recruited mostly through interactions among various components of the rhizosphere, including plant roots and the bulk soil microbiome. We compared the diverse attributes of the core microbiome of wheat rhizosphere communities with wheat (W) and legume (L) forecrops determined by three different methods in this study (membership, composition, and functionality). The conclusions of the three methods of microbiome core definition suggest the presence of generalists, i.e., some representative microorganisms from Proteobacteria, Actinobacteria, Hypomicrobiaceae, Bradyrhizobiaceae, Sphingomonas sp., in the wheat rhizomicrobiome. The relative abundance of the core microbiome accounted for 0.1976% (W) and 0.334% (L)—membership method and 6.425% (W) and 4.253% (L)—composition method. Additionally, bacteria of the specialist group, such as Rhodoplanes sp., are functionally important in the rhizomicrobiome core. This small community is strongly connected with other microbes and is essential for maintenance of the sustainability of certain metabolic pathways. [ABSTRACT FROM AUTHOR]

The EPR spectroscopy was used to determine the structure and physicochemical properties of liposomes prepared from L-α-phosphatidylcholine dipalmitoyl (DPPC) by the modified reverse-phase evaporation method (mREV). EPR study was carried out in the temperature range from 297 K to 340 K i.e. below and above the phase transition temperature TC of DPPC. On the basis of EPR spectra of spin marker 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) incorporated into the liposome, the parameter f was determined. TEMPO dissolves easily in water and in the fluid lamellar smectic liquid-crystaline phase of lipid bilayer but is largely excluded from the solid, gel-phase. Thus TEMPO can be used to observe the change in the partition between aqueous and fluid lipid regions. The change in the relative value of f as a function of temperature for DPPC shows that, in the presence of water excess, this phospholipids undergoes a transition from a “gel phase” to a lamellar smectic liquid crystalline phase. On the basis of EPR spectra of spin marker 2-(3carboxypropyl)-4,4-dimethyl-2-tridecyl-3-oxazolidinloxyl (5-DOXYL) incorporated into liposome, the parameter a′N was determined. The isotropic 14N-hyperfine coupling constant a′N of nitroxide spin label depends on the local environmental polarity. The increase of a′N value reflects the rise of polarity of spin label environment. Temperature, cholesterol and pH dependent structural changes were also described. [ABSTRACT FROM AUTHOR]

Endophytic microbiota plays a role not only in supplying plants with the basic nutrients indispensable for their growth, but also helps them in the mechanisms of adaptation to various environmental stresses (i.e., salinity, drought), which is important in the aspect of crop yields. From the agricultural and biotechnological points of view, the knowledge of endophytes and their roles in increasing crop yields, plant resistance to diseases, and helping to survive environmental stress is extremely desirable. This paper reviews some of the beneficial plant–microbe interactions that might be potentially used in both agriculture (plant growth stimulation effect, adaptation of host organisms in salinity and drought conditions, and support of defense mechanisms in plants), and in biotechnology (bioactive metabolites, application of endophytes for bioremediation and biotransformation processes, and production of biofertilizers and biopreparations). Importantly, relatively recent reports on endophytes from the last 10 years are summarized in this paper. [ABSTRACT FROM AUTHOR]

The metal hyperaccumulator Azolla filiculoides is accompanied by a microbiome potentially supporting plant during exposition to heavy metals. We hypothesized that the microbiome exposition to selected heavy metals will reveal metal tolerant strains. We used Next Generation Sequencing technique to identify possible metal tolerant strains isolated from the metal-treated plant (Pb, Cd, Cr(VI), Ni, Au, Ag). The main dominants were Cyanobacteria and Proteobacteria constituting together more than 97% of all reads. Metal treatment led to changes in the composition of the microbiome and showed significantly higher richness in the Pb-, Cd- and Cr-treated plant in comparison with other (95–105 versus 36–44). In these treatments the share of subdominant Actinobacteria (0.4–0.8%), Firmicutes (0.5–0.9%) and Bacteroidetes (0.2–0.9%) were higher than in non-treated plant (respectively: 0.02, 0.2 and 0.001%) and Ni-, Au- and Ag-treatments (respectively: <0.4%, <0.2% and up to 0.2%). The exception was Au-treatment displaying the abundance 1.86% of Bacteroidetes. In addition, possible metal tolerant genera, namely: Acinetobacter, Asticcacaulis, Anabaena, Bacillus, Brevundimonas, Burkholderia, Dyella, Methyloversatilis, Rhizobium and Staphylococcus, which form the core microbiome, were recognized by combining their abundance in all samples with literature data. Additionally, the presence of known metal tolerant genera was confirmed: Mucilaginibacter, Pseudomonas, Mycobacterium, Corynebacterium, Stenotrophomonas, Clostridium, Micrococcus, Achromobacter, Geobacter, Flavobacterium, Arthrobacter and Delftia. We have evidenced that A. filiculoides possess a microbiome whose representatives belong to metal-resistant species which makes the fern the source of biotechnologically useful microorganisms for remediation processes. [ABSTRACT FROM AUTHOR]

Microbial coal gasification is of great interest due to the necessity to develop more environmentally friendly methods of energy production. The two main lignite deposits in Poland (Bełchatów and Turów) have been studied for their natural methanogenic potential. The biological origin of gases occurring in the investigated strata was confirmed by carbon stable isotope fractionation. Methanogenesis was examined via long-term anaerobic microcosm incubations which were performed using coal extracted from upper- and lower- most parts of the deposits at 10 to 40 °C. Present-day methane formation was distinguished from physical desorption by application of 2-bromoethane sulphonate (BES), an inhibitor of terminal methane formation steps. Furthermore, glycerol dialkyl glycerol tetraethers (GDGTs), were used to reconstruct the palaeoenvironmental conditions and explain how the lignite environment affects the methanogenic consortia. The data obtained reveal that microbial degradation of lignite occurs in the uppermost layers of the coal seam at the Bełchatów lignite mine. Methane release was up to 0.064 ng CH 4 g −1  day −1 at 30 °C. Biomarker analysis shows high abundance of GDGT-0 confirming the presence of methanogenic Archaea and implies that pH was an important factor regulating the development and activity of organic matter-degrading microbiota under neutral conditions as the most favourable for the methanogens. Inactivation of methanogenic pathways by BES led to stimulation of bacterial respiration, which suggests the presence of an active bacterial community, putatively involved in the decomposition of lignin. The biomarker analysis, depicting metabolic capabilities of the microbiota (especially GDGT-0 and GDGT-0/crenarchaeol ratio) and recognition of palaeoenvironmental conditions, is a useful tool to determine the methanogenic potential of coals. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the differences in the bacterial community physiological profiles in soils contaminated with heavy metals versus soils without metal contaminations. The study's contaminated soil originated from the surrounding area of the Szopienice non-ferrous metal smelter (Silesia Region, Poland). The control was soil unexposed to heavy metals. Metal concentration was appraised by flame atomic absorption spectrometry, whereas the the community-level physiological profile was determined with the Biolog EcoPlatesTM system. The soil microbiological activity in both sites was also assessed via dehydrogenase activity. The mean concentrations of metals (Cd and Zn) in contaminated soil samples were in a range from 147.27 to 12265.42 mg kg-1, and the heavy metal contamination brought about a situation where dehydrogenase activity inhibition was observed mostly in the soil surface layers. Our results demonstrated that there is diversity in the physiological profiles of microorganisms inhabiting contaminated and colntrol soils; therefore, for assessment purposes, these were treated as two clusters. Cluster I included colntrol soil samples in which microbial communities utilised most of the available substrates. Cluster II incorporated contaminated soil samples in which a smaller number of the tested substrates was utilised by the contained microorganisms. The physiological profiles of microorganisms inhabiting the contaminated and the colntrol soils are distinctly different. [ABSTRACT FROM AUTHOR]

The choice of appropriate agricultural practices has a major impact on soil quality, crop productivity, and bacterial community structure. The aim of our study was to gain insight into Bacteroidota structure, including the phylum, family, and genus in the context of the application of different agricultural practices (crop rotation, intercropping mixture, long-term maize monoculture) across changing seasons (spring, summer, autumn), which is undoubtedly novel among previous reports on different cropping systems. Additionally, the Spearman correlation test as well as ANOVA and RDA statistical analyses were conducted to expand the information on chemical factors directly affecting Bacteroidota abundance in the soil environment. Bacteroidota were shown to be present with varying abundance depending on the agricultural practice and the season. The highest abundance of Bacteroidota occurred when crop rotation was the main agricultural practice, where the highest average yield was also recorded. Thus, our study identified crop rotation as the best of the three agricultural practices compared. The reduction in the relative abundance of Bacteroidota, in particular Flavobacterium sp. in fields K20 (intercropping) and K21 (monoculture), and the achievement of almost twice the lower average yield in field K21 than in field K3, indicated the poorer quality of these soils. We therefore concluded that the increased abundance of Bacteroidota could indicate good quality agricultural soils. It was also proved that the genera Mucilaginibacter and Edaphobaculum are the most sensitive to soil chemistry over the changing seasons, while the genus Flavobacterium is sensitive to agricultural practices and its presence may indicate good quality of agricultural soils. Statistical analyses indicated that chemical properties have a strong influence on Bacteroidota structure formation in agricultural soils. Overall, our results have evidenced that the Bacteroidota community can be an important indicator of soil quality in studies of soil biological degradation processes, since a decrease in the abundance of these beneficial microorganisms potentially could be connected with reduction of the soil quality, fertility and ultimately affects crop yield. They have also shown that the community of this group of bacteria varies between seasons of the year. • Bacteroidota were shown to be present with varying abundance depending on the agricultural practice and the season. • Crop rotation contributed to the highest Bacteroidota abundance and average yield. • The genera Mucilaginibacter , Edaphobaculum , Pedobacter , and Flavobacterium are important indicators of soil quality. • Soil chemical properties have a strong influence on the Bacteroidota structure formation. [ABSTRACT FROM AUTHOR]

Background: The authors postulate that the recent intensification of the nationalist and xenophobic attitude in Poland and other Eastern European countries is detrimental to public mental health. The xenophobic attitude is accompanied by a higher incidence of anxiety and depression, disputes due to the polarization of opinions, a sense of embarrassment and a sense of contradictions with so-called Christian values, unfavorable demographic predictions and reduced life satisfaction.Discussion: The authors attempt to describe the sequence of adverse events that led to the intensification of xenophobia and characterize the current state of public mental health in European countries. They formulate and propose possible actions which could counteract the consequences of that transformation.Short Conclusion: The actions which may be undertaken to counteract the deterioration of public mental health can be based on the recommendations of so-called 'positive psychology' and 'positive psychiatry' as well as the principles of strengthening local social capital. [ABSTRACT FROM AUTHOR]

An abstract of the article "Synthesis And Properties Of Sulphur Derivatives From T Novolak Production Waste" by Wioletta M. Bajdur and colleagues is presented.

Carbon (C), geologically sequestered in coal, is gradually released to the atmosphere as CH4and CO2. Recent anthropogenic activity (coal mining) has rapidly increased the rate of C reallocation from coal deposits into the atmosphere, which has deleterious effect on the climate as both gases are effective infrared absorbers. In the current study we demonstrate that the coal bearing sedimentary rocks possess potential of biological methane oxidation. Viable methanotrophic bacteria, capable of methane oxidation at ambient air and a range of methane concentrations were found in coalbearing formations of the Upper Silesian (USCB) and Lublin Coal Basins (LCB). Factors controlling activity of the aerobic methanotrophic bacteria in the deep subsurface such as, depth, methane concentration, available electron acceptors, moisture and nutrients availability were investigated along with paleoenvironmental factors (temperature changes during and after burial and paleohydrological infiltration). The distribution and activity of the methanotrophic bacteria in the deep subsurface were found to be influenced by geological conditions among which evolution of paleotemperatures and paleohydrological conditions play a predominant role. The data presented along with analysis of molecular composition of the coalbed gases in various coal basins worldwide has led to the conclusion that aerobic methanotrophy may be a widespread process, which, to our knowledge, so far has not been included in investigations concerning C cycling in the subsurface. [ABSTRACT FROM AUTHOR]

Waste-expanded polystyrene (EPS) and virgin polystyrene (VPS) were converted into ion exchangers by chemical modification. For this purpose, we used silica sulfuric acid as the sulfonating agent and conducted sulfonation under heterogeneous conditions. For VPS, the influence of the quantity of the sulfonating agent, the temperature, and the reaction time on the product properties were studied. As it appeared, silica sulfuric acid simplifies the reaction in comparison with the conventional sulfonation methods. Fourier transform-infrared (FT-IR) spectra and elemental analysis revealed that products were cross-linked and the content of sulfonate groups in a polymer chain varied. Some of the yielded polymers exhibited good water absorption and cation-exchange properties. The ion-exchange capacity (IEC) for chosen products was also determined, and it turned out to be similar to the commercial resin. The batch method was used to study the purification of solutions of Zn2+ and Cu2+ by the obtained resins. The performed study proved the usefulness of waste PS derivatives for the water treatment process. [ABSTRACT FROM AUTHOR]

Simple Summary: Azolla filiculoides L. is an aquatic fern with the potential for degradation and accumulation of pollutants. It is accompanied by microorganisms (a microbiome) that may participate in these processes. Microorganisms showing specific phenotypes may promote plant growth in the presence of pollutants. We intended to identify such beneficial strains by studying their potential for the degradation of given organic compounds and the production of hydrolytic enzymes and phytohormones under heavy metal stress (Pb, Cd, Cr (VI), Ni, Ag, and Au). We found 10 isolates displaying varying phenotypes depending on the stress factor. The most efficient was Delftia sp., which showed potential for both degradation of organics and plant growth promotion. Other strains were more efficient at metabolizing organics or exhibited enzymatic responses in the presence of the studied metals. These identified phenotypes made all strains beneficial in both supporting plants in unfavorable conditions and degradation of organic compounds. A biopreparation containing these strains may be valuable as both a biofertilizer and a bioremediation agent. As an adaptation to unfavorable conditions, microorganisms may represent different phenotypes. Azolla filiculoides L. is a hyperaccumulator of pollutants, but the functions of its microbiome have not been well recognized to date. We aimed to reveal the potential of the microbiome for degradation of organic compounds, as well as its potential to promote plant growth in the presence of heavy metals. We applied the BiologTM Phenotypic Microarrays platform to study the potential of the microbiome for the degradation of 96 carbon compounds and stress factors and assayed the hydrolytic potential and auxin production by the microorganisms in the presence of Pb, Cd, Cr (VI), Ni, Ag, and Au. We found various phenotype changes depending on the stress factor, suggesting a possible dual function of the studied microorganisms, i.e., in bioremediation and as a biofertilizer for plant growth promotion. Delftia sp., Staphylococcus sp. and Microbacterium sp. exhibited high efficacy in metabolizing organic compounds. Delftia sp., Achromobacter sp. and Agrobacterium sp. were efficient in enzymatic responses and were characterized by metal tolerant. Since each strain exhibited individual phenotype changes due to the studied stresses, they may all be beneficial as both biofertilizers and bioremediation agents, especially when combined in one biopreparation. [ABSTRACT FROM AUTHOR]

Simple Summary: Unmasking the overall endophytic bacteria communities from wheat grains may help to identify and describe the microbial colonization of bread and emmer varieties, their link to the bioactive compounds produced, and their possible role in mineral nutrition. The possibility of using microorganisms to improve the microelemental composition of grain is an important food security concern, as approximately one-third of the human population experiences latent starvation caused by Fe (anemia), Zn, or Cu deficiency. Four wheat varieties from T. aestivum L. and T. turgidum subsp. dicoccum were grown in field conditions with low bioavailability of microelements in the soil. Varietal differences in the yield, yield characteristics, and the grain micronutrient concentrations were compared with the endophytic bacteria isolated from the grains. Twelve different bacterial isolates were obtained that represented the genera Staphylococcus, Pantoea, Sphingobium, Bacillus, Kosakonia, and Micrococcus. All studied strains were able to synthesize indole-related compounds (IRCs) with phytohormonal activity. IRCs produced by the bacterial genera Pantoea spp. and Bacillus spp. isolated from high-yielding Oksamyt myronivs'kyi and Holikovs'ka grains may be considered as one of the determinants of the yield of wheat and its nutritional characteristics. Wheat grains are usually low in essential micronutrients. In resolving the problem of grain micronutritional quality, microbe-based technologies, including bacterial endophytes, seem to be promising. Thus, we aimed to (1) isolate and identify grain endophytic bacteria from selected spring wheat varieties (bread Oksamyt myronivs'kyi, Struna myronivs'ka, Dubravka, and emmer Holikovs'ka), which were all grown in field conditions with low bioavailability of microelements, and (2) evaluate the relationship between endophytes' abilities to synthesize auxins and the concentration of Fe, Zn, and Cu in grains. The calculated biological accumulation factor (BAF) allowed for comparing the varietal ability to uptake and transport micronutrients to the grains. For the first time, bacterial endophytes were isolated from grains of emmer wheat T. turgidum subsp. dicoccum. Generally, the 12 different isolates identified in the four varieties belonged to the genera Staphylococcus, Pantoea, Sphingobium, Bacillus, Kosakonia, and Micrococcus (NCBI accession numbers: MT302194—MT302204, MT312840). All the studied strains were able to synthesize the indole-related compounds (IRCs; max: 16.57 µg∙mL−1) detected using the Salkowski reagent. The IRCs produced by the bacterial genera Pantoea spp. and Bacillus spp. isolated from high-yielding Oksamyt myronivs'kyi and Holikovs'ka grains may be considered as one of the determinants of the yield of wheat and its nutritional characteristics. [ABSTRACT FROM AUTHOR]

Due to the growing costs of agricultural production and the need to protect the environment, there has been a need to intensify activities leading to an increase in the effectiveness of natural biological processes. These measures should increase the biodiversity of the environment, enable the adaptation of microorganisms and the protection of plants and soils against the background of the concept of sustainable agricultural development. The soil is an important environment in which many elements are transformed, including nitrogen necessary for the proper yielding of plants. The aim of the article is to present the microbiological aspect of nitrogen transformation, starting with a review of historical findings and then to discuss the progress of the latest developments that have contributed to a detailed understanding of the biochemical reactions occurring during nitrogen transformation in soil. Moreover, the aim of the study is to present the current state of knowledge on the dynamics of nitrogen uptake and conversion by various species of microorganisms and the relationship between the activity of nitrogen microorganisms and nitrogen uptake by plants. The article also includes the latest information on the possibility of using microbiological biostimulants supporting plant growth (PGPR) and protection against the effects of phytopathogens. [ABSTRACT FROM AUTHOR]

Liquid chromatography–tandem mass spectrometry (LC–MS/MS), colorimetry, and bioassays were employed for the evaluation of the ability of endophytic bacterial strains to synthesize indole-related compounds (IRCs) and in particular indole-3-acetic acid (IAA). A total of 54 endophytic strains belonging to seven bacterial genera isolated from tissues of common and spelt wheat cultivars were studied. The endophytic bacteria isolated from different tissues of the tested wheat types were capable of IRCs production, including IAA, which constituted from 1.75% to 52.68% of all IRCs, in in vitro conditions via the tryptophan dependent pathway. The selected post-culture medium was also examined using a plant bioassay. Substantial growth of wheat coleoptile segments treated with the bacterial post-culture medium was observed in several cases. Our data suggest that the studied endophytic bacteria produce auxin-type compounds to support plant development. Summarizing, our approach to use three complementary methods for estimation of IRCs in different endophytic strains provides a comprehensive picture of their effect on wheat growth. [ABSTRACT FROM AUTHOR]

Acidified slurry is a novel organic fertilizer that limits gaseous ammonia emissions and reduces nitrogen losses. Our research aimed to determine the effects of short-term fertilization with acidified slurry on the chemical properties and bacterial community of soil used for maize cultivation. In the months after spreading, raw slurry fertilization had a significant impact on the increase in values of N-NO3. In contrast, soil fertilized with acidified slurry had lower N-NO3 values when compared to raw slurry fertilization treatments. Bacterial sequencing using Illumina MiSeq showed no differences in the genetic diversity of bacterial communities. In all tested soil samples, dominants at the phylum level were Actinobacteria, Proteobacteria, and Acidobacteria, while dominants at the class level were Actinobacteria, Alphaproteobacteria, Thermoleophilia, Gammaproteobacteria, and Acidimicrobiia. The values of biodiversity indices (Shannon index, Simpson index) in tested samples were similar. Our results suggest that short-term fertilization with acidified slurry does not adversely affect the biodiversity and structure of the bacterial communities and has a slight impact on soil chemical properties. [ABSTRACT FROM AUTHOR]

Endophytes are associated with host plants throughout their life history from seed germination to fruit development. One of the most important plant organs colonized by endophytic microbiota is the seed. The aim of this study was to determine the structure of the seed core microbiome inhabiting the endosperms and embryos of eight wheat cultivars with the use of a culture-independent technique. The seeds of Triticum aestivum L. cv. Hondia, Wilejka, STH, Opcja, Tybalt, Euforia and Triticum spelta L. cv. Rokosz and Schwabencorn (producer: Plant Breeding Strzelce Sp. z o.o. Group IHAR) were studied. Rokosz and Hondia were cultured in vitro and in vivo to identify obligatory bacterial endophytes. A restrictive analysis of reads originating from the in vitro plants has demonstrated that the bacterial genera Paenibacillus and Propionibacterium inhabiting Rokosz and Hondia plants have a status of obligatory microorganisms. Greater biodiversity of seed-borne endophytes was found in the seed endosperms than in the embryos. The multiple comparison analysis of the OTU abundance indicated that the seed part significantly influenced the relative abundance. The seed-born microbiome is not statistically significantly dependent on the wheat cultivars; however, it cannot be claimed that every wheat seed is the same. [ABSTRACT FROM AUTHOR]