Two 16-year-old series of experiments with winter wheat grown in rotation after winter oilseed rape were used in the study. The experiments were located in the cold temperate dry and moist climate zones on light soils. Wheat was fertilized with nitrogen in the doses of 40, 80, 120, 160, and 200 kg N·ha⁻¹ per year. Through the several years of the experiment, critical N rates for maximum yield and gross margin from the linear-plus plateau regressions were 149 ± 23.9 and 112 ± 23.6 kg N·ha⁻¹, respectively. The estimated nitrogen indicators for these doses were as follows: nitrogen use efficiency (NUE) 93 and 108%, N surplus (Ns) 6.8 and −10.1 kg·N·ha⁻¹, yield-scaled Ns, N₂O, and NH₃ 3.5 and −0.2; 0.35 and 0.30; 0.31 and 0.25 kg N·Mg⁻¹, respectively. Experiments have shown that two strategies for reducing nitrogen losses on light soils under wheat cultivation are possible: by limiting the N dose to the critical values due to the yield requirements, or due to the gross margin. The analysis of the 11-year data for 2300 farm fields with winter wheat grown on light soils showed that only 10% of them were implementing the first strategy, and as much as 90% chose the second strategy.

Substances of organic origin are seeing increasing use in agriculture as rich sources of nutrients for plants. The aim of this study was to determine the microbiological contamination of sewage sludge and digestate to assess their safe use as fertilizers in Poland. The assessment of microbial soil, sewage sludge and digestate contamination was based on the total number of mesophilic bacteria and Gram-negative bacteria from the Enterobacteriaceae family. The presence of Escherichia coli and Salmonella spp. was identified via culture and the presence of Enterobacteriaceae species was determined via biochemical and molecular methods. In laboratory conditions, the survival of E. coli in soil fertilized with sewage sludge or digestate inoculated with a reference strain was determined. The average concentration of Enterobacteriaceae in soil, sewage sludge and digestate samples was 1.1 × 10⁴ CFU/g, 9.4 × 10⁵ CFU/g and 5.6 × 10⁶ CFU/g, respectively. Escherichia coli was detected in all sample types. From the soil samples, Serratia, Enterobacter, Pantoea, Citrobacter and Pseudomonas genera were identified the most frequently, while in sewage sludge and digestate, E. coli was predominant. Based on the results of our laboratory experiment, it can be concluded that after three weeks, fertilization with organic waste in acceptable doses does not significantly increase soil contamination with Enterobacteriaceae.

Extreme meteorological phenomena resulting from climate change caused by anthropogenic emissions of greenhouse gases (GHG) require the implementation of CO₂ mitigation practices from various industries, including agriculture. Owing to varying soil, climatic, and agrotechnical characteristics, they may have different efficiencies in mitigating soil CO₂ emissions. The aim of this study was to evaluate the impact of three mitigation practices (reduced tillage, deep fertilizer placement, and soil afforestation) on CO₂ emissions from sandy soils in Central and Eastern Europe allowing the prediction of the mitigation effectiveness of these methods. The average soil CO₂-C flux under a moldboard plow system ranged from 218.4 ± 108.4 to 263.7 ± 176.6 mg CO₂-C m⁻² h⁻¹ and under a reduced tillage system ranged from 169.7 ± 118.7 to 163.6 ± 115.2 mg CO₂-C m⁻² h⁻¹ in a year with normal meteorological conditions and under extreme drought conditions, respectively. In the dry growing season, similar amounts of CO₂-C were released from the soil fertilized to the soil surface and after mineral fertilizers application at a depth of 10 cm and 20 cm (133.7 ± 155.8, 132.0 ± 147.5 and 131.0 ± 148.1 mg CO₂-C m⁻² h⁻¹, respectively). Meanwhile, from the forest soil, the average CO₂-C emission in the dry growing season was 123.3 ± 79 mg CO₂-C m⁻² h⁻¹. The obtained results revealed that reduced tillage on sandy soil allowed for reduced CO₂ emissions from the soil by 28.7–61.2% in normal and drought weather, respectively. Under drought conditions, deep fertilizer placement did not reduce CO₂ emissions from sandy soil, and CO₂ emissions from forest soils were even higher than from arable soils.

Introduction: Pantoea is a genus of Gram-negative bacteria from the Erwiniaceae family. These bacteria are opportunistic human pathogens which are widely distributed in plants and soil. This study aimed to reveal the genetic diversity of Pantoea isolates from food and soil, characterise them biochemically and evaluate their drug resistance. Material and Methods: Thirty Pantoea strains were isolated from fresh fruit (n = 2), fresh and minimally processed vegetables (n = 12) and soil samples (n = 16). The genomic DNA was isolated from cultures on nutrient agar, and species were identified by amplification of 16S ribosomal RNA and housekeeping gene fragments and confirmed by sequencing. Virulence gene presence was determined by amplification of the hcp (haemolysin-coregulated protein), vgrG (glycine-valine repeat sequence G), acrA (anti–clustered regularly interspaced short palindromic repeat protein A) and acrB genes. Isolate drug resistance was tested using the disc-diffusion and gradient strip methods. The presence of Ambler class C (AmpC) β-lactamase (βL) and extended-spectrum (ES) βL resistance genes was tested for. Results: Five species were identified: P. agglomerans (n = 24), P. ananatis (n = 1), P. eucalypti (n = 1), P. conspicua (n = 1) and P. vagans (n = 2). The hcp and vrgG virulence genes were detected in 7 and 1 strain, respectively. All strains showed high resistance to cephazolin and cephuroxime, and more than half did so to ampicillin. The production of AmpC βL and ESβL was confirmed in 22 and 25 strains, respectively. Three strains of the Pantoea bacteria, including P. ananatis from leeks and P. agglomerans from arugula and soil, showed resistance to three or more antimicrobial classes. Conclusion: Pantoea spp., including multidrug-resistant strains, in fresh foods pose a potential risk of infection to consumers.

Introduction and objective: Natural fertilizers, sewage sludge, digestates, as well as organic fertilizers produced on their basis, can become a source of parasitological contamination of cultivated land. High concentration of invasive forms of parasites in the soil may pose a threat to human...

Introduction and objective: Soil is a place of accumulation of pathogens threatening life of humans and animals. In accordance with Polish standards, soil is tested for the presence of bacteria of the genus Salmonella, as well as eggs of intestinal parasites of the genera Ascaris, Trichuris and...