Search

The aim of the study was to assess the impact of plant extracts from hemp inflorescences (H10—10% and H20—20%), as well as a mixture of extracts from hemp inflorescences, sage, and tansy leaves (M10—10% and M20—20%) on phytotoxicity and selected physiological and biometric parameters of wheat seedlings, as well as the biological activity of soil in a growth chamber experiment. In all experimental combinations, a low phytotoxicity of the extracts was observed in the form of leaf tip yellowing, classified as first-degree damage or its complete absence. The plant extracts and their mixtures, except for the H20 extract, had an inhibitory effect on the development of fungal pathogens, especially Fusarium spp. The H20 extract increased the fresh and dry weight of root seedlings. The tested extracts also had a positive effect on the chlorophyll content in seedlings. The highest chlorophyll concentrations were recorded for the seedlings sprayed with the M20 extract mixture. The applied plant extracts influenced the activity of soil enzymes. The highest activity of catalase and dehydrogenases was observed after spraying seedlings with M20, while the lowest was recorded after applying H10. Of all the tested groups of soil environment compounds included in the Biolog EcoPlates test, carbohydrates and carboxylic acids were most actively utilized. Conversely, amines and amides constituted the group of compounds utilized the least frequently. The present study demonstrated the high effectiveness of plant extracts on wheat seedlings due to their biocidal action against phytopathogenic fungi and increased biological activity of the soil. This research serves as an initial phase of work, which will aim to verify the results obtained under field conditions, as well as assess the biological stability of the extracts.

The rocks surrounding Wieliczka salt deposits are an extreme, deep subsurface ecosystem that as we studied previously harbors many microorganisms, including methanotrophs. In the presented research bacterial community structure of the Wieliczka Salt Mine was determined as well as the methanotrophic activity of the natural microbiome. Finally, an enrichment culture of methane-consuming methanotrophs was obtained. The research material used in this study consisted of rocks surrounding salt deposits in the Wieliczka Salt Mine. DNA was extracted directly from the pristine rock material, as well as from rocks incubated in an atmosphere containing methane and mineral medium, and from a methanotrophic enrichment culture from this ecosystem. As a result, the study describes the composition of the microbiome in the rocks surrounding the salt deposits, while also explaining how biodiversity changes during the enrichment culture of the methanotrophic bacterial community. The contribution of methanotrophic bacteria ranged from 2.614% in the environmental sample to 64.696% in the bacterial culture. The methanotrophic enrichment culture was predominantly composed of methanotrophs from the genera Methylomonas (48.848%) and Methylomicrobium (15.636%) with methane oxidation rates from 3.353 ± 0.105 to 4.200 ± 0.505 µmol CH4 mL−1 day−1.

The isolation of new bacterial strains from the natural environment can lead to the detection of microorganisms of potential practical importance. The characterization of such microorganisms can be carried out using classical microbiological and molecular biology methods. Currently, studies of newly detected microorganisms are based on sequencing techniques. Sequencing of the full genome can provide information about the origin of the strain, its taxonomic status, and phenotypic characteristics. The studies were conducted using the bacteria Achromobacter sp. 77Bb1 isolated from the maize crop rhizosphere. The bacterial genome was sequenced using Illumina 2 × 150 nt technology. The obtained sequences were analyzed using bioinformatics methods, resulting in 57 contigs and genome containing 6,651,432 nt. Phylogenetic analysis based on 16S rRNA gene sequences enabled the assignment of the analyzed bacteria to the genus Achromobacter. The obtained genome contained genes for 4855 proteins with functional assignment. Some of these genes were connected with xenobiotics biodegradation and metabolisms. All genes for aminobenzoate degradation and almost all for benzoate and styrene degradation were found in the analyzed genome, suggesting that the isolated strain has the potential to be used in natural bioremediation methods.

Terrestrial plants act as ecosystem engineers modifying the flow of energy and matter and creating new habitats for other organisms. This vital concept also encompasses plants' effects on landforms and soils, crucial components of forested landscapes worldwide. In the present study, we investigate how trees through their roots and symbiotic organisms influence soil-weathering processes. The aim of the study was to answer one of the big questions in Earth sciences: how do biological agents, including fungi, acting at the critical interface between the biosphere and the abiotic environment, shape soil and landscape evolution? Within the present study we ask what is the level of fungal activity within root systems of trees and how can it influence biological weathering. The area of interest is in the Poprad River gorge in the southern part of the Sącz Beskidy Mountains, the Outer Western Carpathians. We applied the following analyses: 1) determination of the structural diversity of fungi (ITS1) and 2) assessment of the metabolic profile of soils (Biolog FFPlates). The highest average number of classified genera were fungi which simultaneously carried out pathotrophic, saprotrophic and symbiotrophic functions. Boletales, Agaricales, Cantharellales and Archaeorhizomycetales were the most abundant orders, but in one sample we also found a particularly high proportion of the order Mortierellales. The order Boletales and its family Boletaceae were significantly enriched in rock crack samples, whereas the highest number of differentially abundant taxa was observed in reference samples. The most frequently utilised substrates by fungi were: glycyl-L-glutamic acids, L-ornithine, L-phenylalanine, L-proline, D-galacturonic acid, fumaric acids, D-saccharic acids, succinic acids and N-acetyl-D-glucosamine. Our study demonstrates that the fungal community in the root zone is geochemically active and the organic acids secreted by plant roots in oligotrophic conditions and nutrient limitations significantly affect soil weathering.

Although fungi are regarded as very important components of soils, the knowledge of their community in agricultural (monocultural) soils is still limited. This indicates that soil fungal communities are investigated less intensively than bacteria. Therefore, the main goal of this paper was to evaluate the fungal mycobiome structure in monoculture soils in a culture-independent approach. Firstly, the study was conducted to identify the core mycobiome composition and its variability at different stages of the maize growing season (spring, summer, and autumn). Secondly, we identified and recommended fungal indicators of both sensitivity and resistance to long-term maize monoculture. Two neighboring fields from the Potulicka Foundation area were selected for the study: K20 sown with a Gorzow mixture (intercropping mixture) to improve soil quality after a maize monoculture in 2020 and K21, where long-term (over 30 years) monoculture cultivation was continued. The basic chemical features [acidity, redox potential, total organic carbon (TOC), and moisture] of soils were determined, fungal genetic diversity was assessed by ITS next generation sequencing (NGS) analyses, and biodiversity indices were calculated. The results of the NGS technique facilitated recognition and classification of the fungal mycobiome to the taxonomic genus level and changes in the fungal structure in the three periods (spring, summer, and autumn) were assessed. It was evidenced that the mycobiome composition was dependent on both the seasons and the agricultural practices. It was also found that even a 1-year break in the monoculture in favor of an intercropping mixture improved soil properties thus contributing to higher biodiversity. Mortierella was recommended as a potential indicator of sensitivity to long-term maize cultivation, whereas Solicoccozyma and Exophiala were proposed as indicators of resistance to long-term maize cultivation. We proved that the precision farming principles applied on the Potulicka Foundation farm had a very positive effect on fungal biodiversity, which was high even in the long-term maize monoculture field. Therefore, the monoculture cultivation carried out in this way does not induce biological degradation of monoculture soils but preserves their good biological quality.

Fungi from the genus Diaporthe have been reported as plant pathogens, endophytes, and saprophytes on a wide range of host plants worldwide. Their precise identification is problematic since many Diaporthe species can colonize a single host plant, whereas the same Diaporthe species can inhabit many hosts. Recently, Diaporthe has been proven to be a rich source of bioactive secondary metabolites. In our initial study, 40 Diaporthe isolates were analyzed for their metabolite production. A total of 153 compounds were identified based on their spectroscopic properties—Ultraviolet-visible and mass spectrometry. From these, 43 fungal metabolites were recognized as potential chemotaxonomic markers, mostly belonging to the drimane sesquiterpenoid-phthalide hybrid class. This group included mainly phytotoxic compounds such as cyclopaldic acid, altiloxin A, B, and their derivatives. To the best of our knowledge, this is the first report on the metabolomic studies on Diaporthe eres species complex from fruit trees in the South-Eastern Poland. The results from our study may provide the basis for the future research on the isolation of identified metabolites and on their bioactive potential for agricultural applications as biopesticides or biofertilizers.

As the market indicates a growing interest in organically grown fruit, there is a need for biostimulants to counter the adverse effects of pathogenic fungi and fungal-like-pathogens. Four microbial pathogens (Botrytis cinerea, Verticillium sp., Phytophthora sp., and Colletotrichum sp.) which are the most often causes of strawberry diseases were selected. Five kinds of biostimulants (C1, C2, C3, C4, and C5) containing bacterial consortia were developed to combat the pathogens. The antagonistic effect of selected microorganisms against strawberry pathogens was observed. The effectiveness of various beneficial bacteria in combating fungal pathogens of cv. Honeoye strawberries was compared and the impact of their activity on fruit quality was assessed. The most significant effect on the strawberry firmness was found for the C2 consortium, which provided the strawberries infected with the pathogens group (MIX: B. cinerea, Verticillium sp., Phytophthora sp., and Colletotrichum sp.) with a 140% increase in maximum load in a puncture test compared to the positive control (C0). Strawberries contaminated with Phytophthora sp. after the application of Consortium C4 (C4) showed the largest increase (127%) in soluble solid content (SSC) when compared to the C0. Fruit contaminated with Colletotrichum sp. and B. cinerea after the application of C2 and Consortium 5 (C5), respectively, had the highest levels of anthocyanins and total phenolic content, when compared to C0. The largest increase, which reached as high as 25%, in D-galacturonic acid content was observed for the group of pathogens after Consortium 1 (C1) application. The extraction of strawberry pectin allowed for the study of the rheological properties of pectin solutions; on this basis, strawberry pectin from the control (NC) was distinguished as it showed the highest viscosity (0.137–0.415 Pas). Taking into account the individual effects of bacteria on strawberry pathogenic fungi and fungal-like-pathogens, it is possible to reduce the adverse effects of fungal disease and to improve the properties of strawberries by selecting the appropriate bacterial consortium. Interactions between microorganisms are often complex and not fully understood, which suggests the need for further research in this direction.

The tillage system, which joins soil tillage, fertilisation, and seed sowing in one pass of a machine, is rarely used in cereal cultivation. This research aimed to study whether strip-till and conventional tillage (post-harvest ripping and mixing of stubble, ploughing, pre-sowing fertilisation, and seedbed preparation) differ in plant density, yield components, and grain yield of winter barley cultivated on Cambisol in a region with low rainfall, the annual average is about 500 mm. To reach this aim, a two-year, large-plot experiment was conducted in a production field. The soil within the field was spatially variable in texture, moisture, and chemical and biological properties, CV 2.3% do 29.6%. Strip-till had lower within-field spatial variability of winter barley grain yield than conventional tillage. The standard deviation was 0.36 t ha−1, 0.67 t ha−1 in the first year and 0.12 t ha−1, 0.30 t ha−1 in the second year, respectively. During the period of limited rainfall, strip-till had greater uniformity of plants after emergence; after the winter with low air temperature and a low amount of snow, it had greater plant density. Thus, strip-till can reduce variability of plants and their yield within a field, especially in adverse environmental conditions.

This paper analyses the impact of the diatomaceous earth/peat (DEP; 3:1) microbial carrier on changes in the bacterial microbiome and the development of biofilm in the anaerobic digestion (AD) of confectionery waste, combined with digested sewage sludge as inoculum. The physicochemical properties of the carrier material are presented, with particular focus on its morphological and dispersion characteristics, as well as adsorption and thermal properties. In this respect, the DEP system was found to be a suitable carrier for both mesophilic and thermophilic AD. The evaluation of quantitative and qualitative changes in the genetic diversity of bacterial communities, carried out using next-generation sequencing (NGS), showed that the material has a modifying effect on the bacterial microbiome. While Actinobacteria was the most abundant cluster in the WF-control sample (WF—waste wafers), Firmicutes was the dominant cluster in the digested samples without the carrier (WF-dig.; dig.—digested) and with the carrier (WF + DEP). The same was true for the count of Proteobacteria, which decreased twofold during biodegradation in favor of Synergistetes. The Syntrophomonas cluster was identified as the most abundant genus in the two samples, particularly in WF + DEP. This information was supplemented by observations of morphological features of microorganisms carried out using fluorescence microscopy. The biodegradation process itself had a significant impact on changes in the microbiome of samples taken from anaerobic bioreactors, reducing its biodiversity. As demonstrated by the results of this innovative method, namely the BioFlux microfluidic flow system, the decrease in the number of taxa in the digested samples and the addition of DEP contributed to the microbial adhesion in the microfluidic system and the formation of a stable biofilm.

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.

Studies using soil microcosms are very common, but few involve flooded soils, and comparing the results from such an experiment with natural conditions is unheard of. In the present study, we investigated the biological activity of soil (pH value, dehydrogenases and phosphatase activities) and the metabolic potential (EcoPlate™ Biolog®) of soil microorganisms in three fluvisol subjected to flooding under laboratory and natural conditions. The results indicate that soil flooding under both natural and laboratory conditions affected soil pH, enzymatic activity and metabolic potential (AWCD, average well colour development) of soil microorganisms. Changes in these parameters are more pronounced in the microcosmic experiment than in the field conditions. Furthermore, depending on the characteristics of the soil (i.e., its type, structure, vegetation) some of the soil quality parameters may return to their preflood state. Microcosm studies are needed in environmental ecology and microbiology to predict changes due to various factors, but their scale and course must be carefully planned.

Fungi have increased tolerance to environmental stress (also related to the access of pollutants, e.g., trace elements and polycyclic aromatic hydrocarbons PAHs). The aim of the study was to evaluate the mycobiome and functional diversity of fungi in long-term crude-oil contaminated soils as the potential bioremediators of oil contaminated sites. Samples were taken from three historical oil wells (over a century old) at two distances: within a 0.5 m radius of the oil wells (OWP1, OWP2, and OWP3) and within a 3 m radius from the oil wells as the controls (OW1, OW2, and OW3). Next generation sequencing (for the ITS region) was accompanied with determination of the functional fungal community based on Biolog FFPlates, glomalin related soil protein (GRSP) content, trace element and PAHs concentration. The research hypothesis assumed that long-term natural bioremediation of crude oil contaminated soils can contribute to intensive development of a unique fungal community adapted to the contamination conditions. The identification of such fungi can be of particular importance in soil bioremediation. There were significant differences in the fungal community and functional diversity between the soil samples. The soils collected directly from the oil wells were characterized by higher biological activity and higher diversity of PAH-degrading fungal candidates compared to the soils collected within 3 m of the oil wells. The total glomalin-related soil proteins (T-GRSP) and easily-extractable glomalin-related soil proteins (EE-GRSP) contents were lower in soil samples taken directly from the crude oil well. The control soil (OW) subjected to a long-term natural remediation may already have sufficient conditions for the growth and development of mycorrhizal fungi. The mycobiome of the soils collected directly from the oil wells (OWP1, OWP2, and OWP3) was characterized by a 35% share of PAH-degrading candidates, compared to the soil collected at the 3 m distance from the oil wells (OW1, OW2, and OW3) at < 5%. The main PAH-degrading fungal candidates belong to genera Ilyonectria, Chaetomium, Gibberella, Paraphoma, Schizothecium, Pseudorobillarda, Tetracladium, Ganoderma, Cadophora, Exophiala, Knufia, Mycoleptodiscus, Cyphellophora, Fusicolla, Devriesia, Didymella, Plenodomus, Pyrenochaetopsis, Symbiotaphrina, Phallus, Coprinellus, Plectosphaerella, Septoriella, and Hypholoma. The share of three- and four-ringed PAHs in soil was higher as the distance from the oil well increased. These results may indicate that more effective degradation processes occur closer to the oil wells.

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.

Climate change has an impact on agricultural production, including the greater persistence of plant pathogens in the environment. Therefore, the question arises as to how to effectively and safely protect plants by using chemicals, the number of which is decreasing each year. The aim of this study was to evaluate the fungistatic effect of 2 acetylthiophenethiosemicarbazone (2actpTS) and Cis-jasmonethiosemicarbazone (JTS) against Fusarium culmorum (Fc) on winter wheat seedlings. The influence of thiosemicarbazones (TSs) on the health status and phytotoxicity of seedlings and soil biological activity was investigated. Before TSs application (watering or spraying), soil was infected with F. culmorum (strain No. 37). The substance type and method of its application significantly influenced only the fresh weight of the seedlings. The varying phytotoxicity of the molecules depended primarily on their application method to the plants. The highest seedling phytotoxicity was recorded when compounds were applied during watering and the lowest when they were sprayed. The results showed that the application of substances 2actpTS and JTS, both in the form of watering and spraying, had a positive effect on plant health status, as expressed by the disease index (DI) value. The presence of the infectious agent and the type of chemical compound increased soil enzyme activity. The highest total number of bacteria was found in the soil that was infected with Fc and in soil samples where JTS was applied by watering and spraying. The highest utilization of amines, amides and amino acids by microorganisms was found in the samples where JTS was applied. The obtained results will be used to create intermediate products for the protection of cereals against Fusarium diseases, not only at the stage of germination and tillage of plants, but also at subsequent developmental stages.

Recently, Diaporthe has been considered the most frequently isolated genera of endophytic fungi, having a broad spectrum of host plants and a worldwide distribution. The endophytic Diaporthe strain used in the present work came from the Fungal Collection of Phytopathology and Mycology Subdepartment, University of Life Sciences in Lublin (Poland), and was isolated from healthy Prunus domestica shoots during previous studies. Due to the possibility of using the Diaporthe endophytes as a promising option for plant disease management, the main goal of the research was to study the antagonistic effect of endophytic Diaporthe strain against six phytopathogens: Verticillium dahliae, Botrytis cinerea, Fusarium avenaceum, F. sprotrichioides, Alternaria alternata, and Trichothecium roseum based on the dual culture assay and to determine the catabolic profile of the endophyte by using Biolog FF Plates. The dual-culture test assay revealed the ability of the endophytic Diaporthe to limit the growth of all tested pathogens. The growth inhibition percentage ranged from 20% (V. dahliae) to 40% (T. roseum). A distinct zone of inhibition occurred between the endophytic Diaporthe and the pathogens T. roseum, V. dahliae, and B. cinerea in the co-growth combinations. As for the catabolic profile results, the most intensive utilization of carbon substrates was observed after 168 h of incubation. The growth of the analyzed strain was observed on 79 media containing carbohydrates, carboxylic acids, amino acids, amines and amides, polymers, and others. The most effective decomposition was observed in the polymers group, the least in amines and amides. Molecular identification indicated that this strain was closely related to the Diaporthe eres species complex.

Bioenergy crops play an ecologically and economically fundamental role as an alternative to agri-food productions and as renewable energy sources. Thus far, less attention has been given to assessing microbiological indicators of soil quality in bioenergy crops on abandoned land. The current study assessed microbial and biochemical properties of two soils with different textures in agroforestry plantations of Paulownia elongata × Paulownia fortunei, with regard to the analysis of potential for the reclamation and redevelopment of abandoned lands. The soil samples were characterised by measuring microbial biomass C and N, key enzyme activities, and determining the community-level physiological profiles (CLPP) using Biolog EcoPlates. Soil texture, sampling time (June and October), and distance of sampling (0.1 m and 1 m from a tree) had significant effects on microbiological properties. Moreover, dehydrogenases and acid phosphatase activities as well as microbial biomass C and N decreased with distance from the trees, and were significantly higher in the October than in the June. The community-level physiological profiles (CLPP) and diversity indices showed a similar trend to other parameters of biological activity. The results showed that there were significant differences in the AWCD (average well-colour development) of all carbon sources among the Paulownia microbial communities (p < 0.05). In summary, already after one year of tree planting, a statistically significant increase in microbial activity was found, regardless of soil texture, when evaluated by various methods. This proves the value of the Paulownia as fast-growing plant for recultivation and improvement of soil quality on abandoned land.

The aim of the study was to evaluate the glomalins content (total glomalin (TG), easily extractable glomalin (EEG) and glomalin-related soil proteins (GRSP)) in the soil under winter wheat from different crop production systems. The experiment involved four different cultivation systems: organic, integrated (INT), conventional (CON), monoculture-conventional (MON). The highest content of TG and GRSP proteins were observed in organic system. A strong positive correlation was observed between the total number of glomalins and dehydrogenase activity and organic matter. A strong correlation between TG and GRSP content was observed (r = 0.93) as well as between EEG and GRSP (r = 0.79). The highest yields of winter wheat were observed in CON (9.12 t/ha) and INT (9.04 t/ha) systems, while the lowest in monoculture (4.47 t/ha).

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.

Methane and carbon dioxide are one of the most important greenhouse gases and significant components of the carbon cycle. Biogeochemical methane transformation may occur even in the extreme conditions of deep subsurface ecosystems. This study presents methane-related biological processes in saline sediments of the Miocene Wieliczka Formation, Poland. Rock samples (W2, W3, and W4) differed in lithology (clayey salt with veins of fibrous salt and lenses of gypsum and anhydrite; siltstone and sandstone; siltstone with veins of fibrous salt and lenses of anhydrite) and the accompanying salt type (spiza salts or green salt). Microbial communities present in the Miocene strata were studied using activity measurements and high throughput sequencing. Biological activity (i.e., carbon dioxide and methane production or methane oxidation) occurred in all of the studied clayey salt and siltstone samples but mainly under water-saturated conditions. Microcosm studies performed at elevated moisture created more convenient conditions for the activity of both methanogenic and methanotrophic microorganisms than the intact sediments. This points to the fact that water activity is an important factor regulating microbial activity in saline subsurface sediments. Generally, respiration was higher in anaerobic conditions and ranged from 36 ± 2 (W2200%t.w.c) to 48 ± 4 (W3200%t.w.c) nmol CO2 gdw−1 day−1. Methanogenic activity was the highest in siltstone and sandstone (W3, 0.025 ± 0.018 nmol CH4 gdw−1 day−1), while aerobic methanotrophic activity was the highest in siltstone with salt and anhydrite (W4, 220 ± 66 nmol CH4 gdw−1 day−1). The relative abundance of CH4-utilizing microorganisms (Methylomicrobium, Methylomonas, Methylocystis) constituted 0.7–3.6% of all taxa. Methanogens were represented by Methanobacterium (0.01–0.5%). The methane-related microbes were accompanied by a significant number of unclassified microorganisms (3–64%) and those of the Bacillus genus (4.5–91%). The stable isotope composition of the CO2 and CH4 trapped in the sediments suggests that methane oxidation could have influenced δ13CCH4, especially in W3 and W4.

The article aims to present results of research on anaerobic digestion (AD) of waste wafers (WF-control) and co-substrate system–waste wafers and cheese (WFC-control), combined with digested sewage sludge, as inoculum. The purpose of this paper is to confirm the outcome of adding silica/lignin (S/L; 4:1) material, as a microbial carrier, on the process performance and genetic diversity of microbial communities. The experiment was conducted in a laboratory under mesophilic conditions, in a periodical operation mode of bioreactors. Selected physicochemical parameters of the tested carrier, along with the microstructure and thermal stability, were determined. Substrates, batches and fermenting slurries were subjected to standard parameter analysis. As part of the conducted analysis, samples of fermented food were also tested for total bacterial count, dehydrogenase activity. Additionally, DNA extraction and next-generation sequencing (NGS) were carried out. As a result of the conducted study, an increase in the volume of produced biogas was recorded for samples fermented with S/L carrier: in the case of WF + S/L by 18.18% to a cumulative biogas yield of 833.35 m3 Mg−1 VS, and in the case of WFC + S/L by 17.49% to a yield of 950.64 m3 Mg−1 VS. The largest total bacterial count, during the process of dehydrogenase activity, was maintained in the WFC + S/L system. The largest bacterial biodiversity was recorded in samples fermented with the addition of cheese, both in the case of the control variant and in the variant when the carrier was used. In contrast, three phyla of bacteria Firmicutes, Proteobacteria and Actinobacteria predominated in all experimental facilities.

The aim of the study was to compare soil respiration depending on different agricultural practices before sowing of maize (Zea mays L.). Results of the study were derived from the field experiment that was carried out in 2013-2015; the research indicates that soil respiration depends on cultivation method. The highest soil respiration was recorded in maize cultivation in monoculture using full tillage. The simplifications in maize cultivation caused a decrease of soil respiration, especially in direct sowing. The lowest level of this parameter was recorded in monoculture in direct sowing. Compared with other treatments, such as direct sowing, reduced tillage and crop rotation, soil respiration was higher by 65, 55 and 12%, respectively. The statistically significant differences in soil respiration in the tested agricultural practices were observed in the first date of measurement in all years of the study. The higher soil respiration values were noted in autumn. The yield of maize correlated with soil respiration, but stronger relationship was noted between soil respiration and grain yield of maize than straw yield. The simple regression analysis showed no linear relationship between soil respiration and evaporation, changes in soil moisture and biochemical parameters such as soil dehydrogenase activity, acid and alkaline phosphatase.

The aim of the study was to compare the activity and functional biodiversity in soil under two different cereals: common maize and winter wheat, both grown in the same pattern of cultivation techniques: conventional (to 25 cm depth) and reduced (to 10 cm depth). Soil samples for comparative analysis were collected at the same time (July 2016) at a long-term field experiment, which was carried out in 2013-2016. Soil biological activity was determined by measurement of dehydrogenases activity (DHa) with TTC (2,3,5-triphenyltetrazolium chloride) application, microbial biomass carbon (MBC) and nitrogen (MBN) content by fumigation-extraction method, and functional diversity of soil microorganisms using the Biolog EcoPlate System. The results demonstrated that the cultivation technique had a greater impact on the soil biological activity, compared to the type of cereal. Higher biological activity was found in the soil under reduced tillage in both cereals. Calculated correlations showed that DHa, MBC, MBN and acid phosphatases were positively correlated with each other. The negative correlation obtained between yield and biological parameters of activity in soil was not expected.

The aim of the study was to determine the glycoproteins content (total glomalin (TG), easily extractable glomalin (EEG) and soil proteins related to glomalin (GRSP)) in soil under long-term monoculture of maize. Soil microbiological and biochemical properties, including microbial biomass and enzymatic activity were also assessed. The presence of total, easily-extractable glomalin and soil proteins related to glomalin was dependent on both the growth phase of the plant and tillage system. The highest content of glomalin was detected in the soils under maize in direct sowing and reduced tillage. The glomalin content was correlated with soil biological activity. The linear regression was observed between TG and GRSP content, but no linear relationship was found between GRSP and Corg. The principal component analysis showed the strong correlations between the parameters of soil quality and biodiversity indicators. Selected indicators of soil microbial parameters explained 52.27% biological variability in soils.

Soil microbial functional diversity under maize grown in different agricultural management practices was determined using the Biolog EcoPlates and other microbial and biochemical methods. Comparisons of substrate utilization and the diversity indices showed differences in community composition of microorganisms related to different cultivation techniques and seasons. The soil samples collected in spring were characterized by statistically significant lower indices of biological activity in comparison to the soil collected from the flowering stage of maize. The soils collected in spring from the plots with full tillage had a similarly high biological activity as the soils obtained from maize flowering season. The principal component of PC analysis, showed the strong correlation between the parameters of soil quality and biodiversity indicators. Selected indicators of soil microbial diversity explained 71.51% of biological variability in soils. Based on the PC analysis, two major groups of soils have been indicated. Management practices and seasons were two important factors affecting soil microbial communities.

The aim of this research was a preliminary evaluation of the effectiveness of using three preparations which improve soil fertility and yield of plants. Field tests with microbial products: EM (effective microorganisms), EmFarma Plus and UGmax were carried out in the Agricultural Research Centre in Grabowo, Poland. The experimental plants were: spring triticale, spring barley and winter wheat. Bioproducts were applied directly into stubble or straw left in the field after harvesting grain and straw with an addition of nitrogen and were compared against control treatments, without the use of the above preparations. The implied treatments are determined for soil biological activity and the basic chemical properties of the soil. The microbiological tests showed a statistically significant difference between the control treatments and treatments with EM and UGmax preparations (a statistically significant increase in microbial biomass and activity of dehydrogenases). Analysis of principal component analysis (PCA) explained 52.54% of the variation and separated the three groups: I (UGmax), II (EM) and III (control and EmFarma Plus). It was found that the average yield of triticale grains was approximately only by 4% higher in treatments where EM and EmFarma Plus were applied, while in treatments with UGmax, triticale yielded at control level.

The aim of the study was to investigate fungal genetic diversity in eight different types of soil in a long-term microplot experiment founded in 1881 in Puławy, Poland. The experiment consists of eight plots (14 m2), each 1 m deep with concrete walls, filled with profiles of different soils. The soils represent the most common Polish soil types (Cambic Leptosol, Fluvic Cambisol, Gleyic Chernozem, Cambisol and Haplic Cambisol, two Brunic Arenosols and Haplic Luvisol). Each soil was characterized by different pH (from 4.0 to 7.5) and organic carbon content (4.5–21.3 g kg-1). The soil structure was not destroyed by compaction because the soils had always been cultivated by hand. The same plant species were always grown in all plots at the same time and the soils received the same fertilization. Moreover, the soils were always under the same weather conditions. Ascomycota was the most abundant phylum in all samples, ranging from 70 to 90% of total fungi. Some genera (Mortierella, Solicoccozyma, and Mycosphaerella) were found to be adapted to a wide range of pH. Acidic soils were dominated by Talaromyces, Cladophialophora, Devriesia, and Saitozyma, while good quality soils primarily consisted of Plectosphaerella, Tetracladium, and Mortierella. The study confirmed previous reports that pH has a decisive influence on soil fungal diversity, but also indicated the strong impact of soil type itself. These studies have launched a new cycle of research in these historical soil profiles.

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.

The aim was to assess plant driven changes in the activity and diversity of microorganisms in the top layer of the zinc and lead smelter waste piles. The study sites comprised two types (flotation waste—FW and slag waste—SW) of smelter waste deposits in Piekary Slaskie, Poland. Cadmium, zinc, lead, and arsenic contents in these technosols were extremely high. The root zone of 8 spontaneous plant species (FW—Thymus serpyllum, Silene vulgaris, Solidago virgaurea, Echium vulgare, and Rumex acetosa; and SW—Verbascum thapsus; Solidago gigantea, Eupatorium cannabinum) and barren areas of each waste deposit were sampled. We observed a significant difference in microbial characteristics attributed to different plant species. The enzymatic activity was mostly driven by plant-microbial interactions and it was significantly greater in soil affected by plants than in bulk soil. Furthermore, as it was revealed by BIOLOG Ecoplate analysis, microorganisms inhabiting barren areas of the waste piles rely on significantly different sources of carbon than those found in the zone affected by spontaneous plants. Among phyla, Actinobacteriota were the most abundant, contributing to at least 25% of the total abundance. Bacteria belonging to Blastococcus genera were the most abundant with the substantial contribution of Nocardioides and Pseudonocardia, especially in the root zone. The contribution of unclassified bacteria was high—up to 38% of the total abundance. This demonstrates the unique character of bacterial communities in the smelter waste.

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.

The aim of the study was to evaluate the influence of mycorrhizal fungi (MF) and irrigation on biological properties of sweet pepper rhizosphere in organic field cultivation. For this purpose, MF were applied to plants in the form of commercial mycorrhizal inoculum (Rhizophagus aggregatus, R. intraradices, Claroideoglomus etunicatum, Endogone mosseae, Funneliformis caledonium, and Gigaspora margarita) and irrigation according to the combinations: mycorrhized plants (PM), mycorrhized and irrigated plants (PMI), and irrigated plants (PI). Plants without MF and irrigation served as the absolute control (P). The study used classic and molecular techniques, assessing catalase activity, biodiversity of soil microorganisms (soil DNA analysis), and the Community-Level Physiological Profiles (CLPP) analysis using Biolog EcoPlates. The highest catalase activity was recorded in the control and mycorrhized soil sample. The highest total number of bacteria was noted in the rhizosphere of control plants (P) and irrigated plants, while the lowest number in the rhizosphere of mycorrhized and irrigated plants. Plant irrigation contributed to the increase in the total number of fungi in the rhizosphere. The rhizospheric soil of PM and PMI were characterized by the highest utilization of amines, amides, and amino acids, whereas the lowest level of utilization was detected in the P and PI rhizospheres. The highest biodiversity and metabolic activity were observed in the rhizospheres from the PMI and PM samples, whereas lower catabolic activity were recorded in the P and PI rhizospheres. The mycorrhization of crops improved the biological properties of the rhizosphere, especially under conditions of drought stress.

Prolonged drought and extreme precipitation can have a significant impact on the activity and structure of soil microbial communities. The aim of the study was to assess the impact of drought length on the dynamics of mineral nitrogen, enzyme activities and bacterial diversity in two soils of different texture (sand and silt loam, according to USDA classification). An additional objective was to evaluate the effect of compost on the alleviation of soil microbial responses to stress conditions, i.e. alternating periods of drought and excessive soil moisture. The pot study was carried out in a greenhouse under controlled conditions. Compost was added at an amount equal to 3% of soil to the sandy soil, which was characterised by a significantly lower water retention capacity. Specific levels of water stress conditions were created through application of drought and soil watering periods. For each soil, four levels of moisture regimes were set-up, including optimal conditions kept at 60% of field water holding capacity, and three levels of water stress: The low level—2 week period without watering; the medium level—1 month drought period followed by watering to full but short-term soil saturation with water; and the high level—2 month drought period followed by full and long-term saturation with the same total amount of water, as in other variants. The soil water regime strongly modified the activities of dehydrogenases and acid and alkaline phosphatase, as well as the bacterial diversity. Loamy soil exhibited greater resistance to the inhibition of soil enzymatic activity. After irrigation, following both a 1 month and 2 month drought, the enzyme activities and nitrification largely recovered in soil with a loamy texture. Drought induced substantial shifts in the functional diversity of bacterial communities. The use of such C substrates, as carboxylic and acetic acids, was strongly inhibited by water deficit. Water deficit induced changes in the relative abundances of particular phyla, for example, an increase in Acidobacteria or a decrease in Verrucomicrobia. The study clearly proves the greater susceptibility of microbial communities to drought in sandy soils and the important role of exogenous organic matter in protecting microbial activity in drought periods.

The aim of this study was to analyse the genetic and phenotypic differentiation of bacteria isolated from root nodules of Trifolium rubens, a rare clover species. The symbiotic compatibility of selected isolates was investigated using two agronomically important plants, red clover (Trifolium pratense L.) and pea (Pisum sativum L.). A high genetic diversity of analysed strains was shown using the Enterobacterial Repetitive Intergenic Consensus Polymerase Chain Reaction (ERIC-PCR) method. Most of the strains showed a high similarity to R. leguminosarum in the 16S rRNA sequence. Two strains were identified as Agrobacterium spp. There was a strong positive correlation between fresh clover weight and the number of root nodules and a statistically significant increase in the number of the root nodules in selected strains compared to the negative control. Phenotypic tests and BIOLOG analysis showed the ability of the analysed strains to grow in different experimental conditions (pH = 6–10, 0.5–3% NaCl, different carbon and nitrogen sources), which makes them suitable for application as an agronomically important factor.

The aim of the study was to evaluate the changes in glomalin-related soil proteins (GRSP) content, microbial diversity and soil physical quality depending on the type of soil measures of soil improvement and changes in soil health. The study was based on a 100-year stationary field microplot experiment where the soil profiles were collected with preserving the natural soil horizons. The microplot experiment was carried out on eight different soil types: Brunic Arenosol (Dystric I), Rendzic Leptosol, Fluvic Cambisol, Haplic Cambisol (Eutric), Gleyic Phaeozem, Brunic Arenosol (Dystric II), Haplic Cambisol (Eutric II) and Haplic Cambisol (Dystric). These soils are the most common types of agricultural soils in Poland. Relatively significant correlations with the soil quality, physical parameters and the glomalin-related soil proteins have been found. The study determined the total GRSP (T-GRSP) and easily extractable GRSP (EE-GRSP) levels in soils as well as the soil physical quality index and soil’s microbial biodiversity. The GRSP depended on the type of soil and correlated with S-Index and also was responsible for the unique chemical and physical properties of soils. Soils characterized by the highest T-GRSP content belonged to the group of very good and good soil physical quality characterized also by high biological activity, for which there were strong correlations with such parameters as dehydrogenase activity (DHA), microbial biomass content (MBC), microbial nitrogen content (MBN) and total bacteria number (B). The highest T-GRSP content and higher microbial diversity were found in Gleyic Phaeozem, Rendzic Leptosol and Fluvic Cambisol. The T-GRSP and EE-GRSP content were additionally correlated with the number of AMF spores. Very poor and poor soil physical quality according to S-Index characterized Brunic Arenosol (Dystric I) and Haplic Cambisol (Dystric). This research indicates that a specific edaphone of soil microorganisms and GRSP content may be of great importance when assessing a soil’s quality and improvements in soil health. The abundance of glomalin-producing fungi significantly affects the quality of the soil. This effect is particularly important for agricultural soils are threatened by ongoing land degradation.

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.

Soil contamination with petroleum, especially in the area of oil wells, is a serious environmental problem. Restoring soil subjected to long-term pollution to its original state is very difficult. Under such conditions, unique bacterial communities develop in the soil that are adapted to the contaminated conditions. Analysis of the structure and function of these microorganisms can be a source of valuable information with regard to bioremediation. The aim of this study was to evaluate structural and functional diversity of the bacterial communities in soils with long-term impacts from petroleum. Samples were taken from the three oldest oil wells at the Crude Oil Mine site in Węglówka, Poland; the oldest was established in 1888. They were collected at 2 distances: (1) within a radius of 0.5 m from the oil wells, representing soil strongly contaminated with petroleum; and (2) 3 m from the oil wells as the controls. The samples were analyzed by 16S rRNA sequencing and the community level physiological profiling (CLPP) method in order to better understand both the genetic and functional structure of soil collected from under oil wells. Significant differences were found in the soil samples with regard to bacterial communities. The soils taken within 0.5 m of the oil wells were characterized by the highest biodiversity indexes. Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria were strongly correlated with biological activity in these soils. Families of Alphaproteobacteria were also dominant, including: Bradyrhizobiaceae, Rhizobiaceae, Rhodobacteraceae, Acetobacteraceae, Hyphomicrobiaceae, and Sphingomonadaceae. The study showed that the long term contamination of soil changes bacterial communities and their metabolic activity. Even so, natural bioremediation leads to the formation of specific groups of bacteria that actively grow at the site of contamination in the soil.

Fungal diversity in the soil may be limited under natural conditions by inappropriate environmental factors such as: nutrient resources, biotic and abiotic factors, tillage system and microbial interactions that prevent the occurrence or survival of the species in the environment. The aim of this paper was to determine fungal genetic diversity and community level physiological profiling of microbial communities in the soil under long-term maize monoculture. The experimental scheme involved four cultivation techniques: direct sowing (DS), reduced tillage (RT), full tillage (FT), and crop rotation (CR). Soil samples were taken in two stages: before sowing of maize (DSBS-direct sowing, RTBS-reduced tillage, FTBS-full tillage, CRBS-crop rotation) and the flowering stage of maize growth (DSF-direct sowing, RTF-reduced tillage, FTF-full tillage, CRF-crop rotation). The following plants were used in the crop rotation: spring barley, winter wheat and maize. The study included fungal genetic diversity assessment by ITS-1 next generation sequencing (NGS) analyses as well as the characterization of the catabolic potential of microbial communities (Biolog EcoPlates) in the soil under long-term monoculture of maize using different cultivation techniques. The results obtained from the ITS-1 NGS technique enabled to classify and correlate the fungi species or genus to the soil metabolome. The research methods used in this paper have contributed to a better understanding of genetic diversity and composition of the population of fungi in the soil under the influence of the changes that have occurred in the soil under long-term maize cultivation. In all cultivation techniques, the season had a great influence on the fungal genetic structure in the soil. Significant differences were found on the family level (P = 0.032, F = 3.895), genus level (P = 0.026, F = 3.313) and on the species level (P = 0.033, F = 2.718). This study has shown that: (1) fungal diversity was changed under the influence different cultivation techniques; (2) techniques of maize cultivation and season were an important factors that can influence the biochemical activity of soil. Maize cultivated in direct sowing did not cause negative changes in the fungal structure, even making it more stable during seasonal changes; (3) full tillage and crop rotation may change fungal community and soil function.

Mycorrhizal symbiosis is known since the 19th century and has been described as the coexistence of fungus with the roots of vascular plants. Root colonization by endomycorrhizal fungi causes changes in the quantity and quality of exudates produced by roots. The mycorrhiza may also affect plants’ health status, their competitiveness and succession in eco-systems, and the formation of soil aggregates. The presence of a symbiont in the roots of plants causes a direct and indirect effect on rhizosphere microorganisms, fixing free nitrogen and transforming compounds constituting nutrient substrates for plants. The physiological and morphological relations of AMF with the plant promote its vitality and competitiveness by increasing resistance to abiotic and biotic stresses. Effective activation of the plant immune responses may occur, not only locally but also systemically. Mycorrhizal fungi, through the change of the composition and amount of root exudates, have influence on the development and activity of the communities of soil microorganisms. Certain soil bio-controlling microorganisms frequently showing synergism of the protective effect on plants together with AMF. In some cases, however, no positive interaction of selected microorganisms and endomycorrhizal fungi is observed. Double inoculation with the some species of bacteria and the mycorrhizal fungus can cause a decrease in the yielding the plants. Mycoparasitism of AMF spores and hyphae is also encountered in interaction between saprophytic fungi and AMF. This phenomenon is based on the lytic abilities of some fungi species which can lower the level of colonization and the effectiveness of mycorrhizal symbiosis with plants. Good knowledge of plant symbiosis with endomycorrhizal fungi and activity of these fungi in soils is necessary for their use in plant production.

This study focused on the determination of both catabolic and genetic fingerprinting of bacteria inhabiting soil contaminated with car fuels. A surface layer (0–20 cm) of Mollic Gleysol was used for the experiment and was contaminated with car fuels—unleaded 95-octane petrol and diesel at a dose of 15 g per 10 g of soil. The experiment lasted 42 days and was performed at 20 °C. The metabolic potential of soil bacterial communities was evaluated using the Biolog EcoPlate system. The results demonstrated that petroleum substances influenced the structure of the microbial populations and their catabolic activity. The Arthrobacter, Paenibacillus, and Pseudomonas genera were found in diesel-contaminated soil, whilst Bacillus and Microbacterium were found in petrol-contaminated soil. Rhodococcus species were identified in both variants of impurities, suggesting the widest capability of car fuel degradation by this bacterial genus. The contamination with unleaded 95-octane petrol caused rapid inhibition of the metabolic activity of soil bacteria in contrast to the diesel treatment, where high metabolic activity of bacteria was observed until the end of the incubation period. Higher toxicity of petrol in comparison with diesel car fuel was evidenced.

Introduction. In the vast literature concerning the development of the intervertebral discs controversies exist as to the period of differentiation and structure of the nucleus pulposus and annulus fibrosus. These controversies result from different determination of age of the investigated embryos. Aim. Using embryos from departmental collection age of which was established according to international Carnegie staging and expressed in postfertilizational days, the differentiation of the intervertebral discs was traced. Material and methods. Study was performed on 34 embryos at developmental stages 13–23 (32–56 days). Embryos were serially sectioned in sagittal, frontal and horizontal planes. Sections were stained with various histological methods and impregnated with silver. Results. Division of sclerotomes into loose cranial and dense caudal zones (sclerotomites) was observed in embryos aged 32 days (stage 13). The intervertebral disc developed from the dense zone of sclerotome and was well recognized in embryos aged 33 days (stage 14). At the end of fifth week (embryos at stage 15, 36 days) the annulus fibrosus and the nucleus pulposus were seen. The annulus fibrosus differentiated into lateral and medial zones. Within the lateral zone cells were arranged into circular rows. These rows were considered as the first stage of laminar structure. In further developmental stages the laminae occupied both zones of the annulus fibrosus. Conclusions. The intervertebral discs develop from the dense zone of the sclerotome which is evident in embryos at stage 13 (32 days). Discs differentiate in embryos aged 33 days, when the nucleus pulposus and annulus fibrosus are recognized. In embryos aged 36 days in the annulus fibrosus circular rows forming laminar arrangement are seen.