Tatyana Stefanovska

The purpose of this study was to evaluate early chemical and biological responses of soil to miscan-thus-derived biochar in a controlled pot system with sweet corn. A short-term pot experiment was conducted using natural soil amended with miscanthus-derived biochar at different rates. Sweet corn was grown under controlled conditions, and soil samples were collected at the start of the experiment and after 60 days in both the with and without plants treatments. Biochar application increased total organic carbon content and modified several soil chemical properties, including nutrient availability, oxidation-reduction potential, and electrical conductivity. Total nematode abundance increased by up to 90% in biochar-amended soils compared with the control, with the strongest response observed in bacterivorous nematodes, indicating stimulation of bacterial energy channels. Multivariate analysis confirmed that soil carbon status and nitrogen availability were the main factors structuring nematode community composition. Overall, these findings show that short-term biochar amendment primarily enhances bacterial-driven soil processes, supporting the use of nematode functional indicators for early assessment of soil response in horticultural systems.

S: Land contamination by potentially toxic elements, petroleum hydrocarbons, pesticides, and other pollutants represents a major environmental challenge that affects soil health and ecosystem functioning. Amendment-assisted phytoremediation using perennial energy crops has emerged as a promising strategy for restoring contaminated and marginal lands, while soil nematodes are increasingly recognized as sensitive indicators of ecological disturbance and recovery. A comprehensive analysis of published studies was conducted to evaluate nematode responses to potentially toxic elements and hydrocarbons in phytoremediation systems amended with biochar and ash, with particular attention to nematode abundance, diversity, trophic structure, and ecological indices. The review also examined systems involving perennial energy crops, especially Miscanthus × giganteus. Available evidence indicates that nematode responses to contaminants and amendments are strongly context-dependent and influenced by contaminant type, concentration, soil properties, amendment characteristics, and vegetation system. Bacterivorous nematodes frequently exhibit greater tolerance to contamination, whereas omnivores and predators are generally more sensitive indicators of ecological disturbance. Biochar commonly suppresses plant-parasitic nematodes while having variable effects on other trophic groups, depending on feedstock type and application rate. Ash amendments may also exhibit nematicidal effects but can negatively affect community balance at high application rates. In systems involving Miscanthus × giganteus , amendment-induced shifts in nematode communities reflect both soil recovery processes and persistent ecological disturbance. Therefore, nematode communities provide valuable insight into soil ecological functioning and remediation efficiency and represent informative bioindicators for assessing the sustainability of amendment-assisted phytoremediation strategies in contaminated soils.

The leaf nematode Aphelenchoides fragariae is one of the most serious pathogens of strawberries, causing significant yield losses. In search of environmentally friendly alternatives to chemical control, we evaluated the potential of vermicompost (Ve) and silver ions (Ag+) to suppress nematode populations. An experiment with four replicates was conducted to evaluate the effects of vermicompost and nanosilver on the leaf nematode A. fragariae and the yield of strawberry (Fragaria × ananassa). The study was conducted at The National Institute of Horticultural Research in Skierniewice in concrete rings (150 cm in diameter and 60 cm in depth) filled with medium sandy soil. Treatments included the application of vermicompost and Ag+, while untreated soil served as the control. Nematode population density, and total fruit yield were recorded in 2022 and 2023. The results demonstrated a significant decline in nematode populations compared with the control. Strawberry yields in 2022 and 2023 were 5.69 t/ha in the control, 6.61 t/ha with vermicompost (+0.92 t/ha), and 6.72 t/ha with silver nanoparticles (+1.03 t/ha). In the vermicompost treatment, the population of A. fragariae decreased by more than 51% in 2022 and by 79% in 2023. A similarly strong reduction was observed for nanosilver (Ag⁺), which lowered the nematode population by over 35% in 2022 and by 69% in 2023.

Addressing the challenges of land degradation, energy transition, and sustainable agriculture requires innovative, multifunctional crops. Miscanthus × giganteus (M×g) has emerged as a particularly promising candidate, offering both substantial bioenergy potential and significant contributions to environmental restoration. Rather than competing with food crops for arable land, M×g thrives on marginal and lowquality soils, offering a low-input cultivation model with high biomass yield. This species is particularly valued for its contribution to carbon mitigation strategies. Its deep root system enables long-term carbon storage in soils while improving structure, fertility, and resistance to erosion. M×g also exhibits phytoremediation potential through the phytoextraction, making it suitable for rehabilitating contaminated or overused lands. Beyond combustion-based energy, M×g biomass serves as a feedstock for a variety of industrial and agricultural products. These include but are not limited to insulation boards, biodegradable packaging, animal bedding, molded bio-composites, second-generation bioethanol, biogas. The material’s versatility makes it in green manufacturing and sustainable construction. Recent research has expanded interest in how plant biostimulants and growth regulators can further optimize M×g performance under stress conditions. This adaptability and broad utility position M×g as a strategic crop for integrated land use systems. Furthermore, there is growing promise in using Miscanthus for biochar production, which can further enhance its role in sustainable agriculture and carbon sequestration. This dual functionality — as a renewable energy source and a tool for soil improvement — makes M×g a valuable asset in efforts to mitigate climate change while enhancing the resilience of agroecosystems.

The impact of acetamiprid-based insecticides on the survival and activity of entomopathogenic nematodes (EPNs) was evaluated in laboratory, focusing on two species, Steinernema feltiae and Heterorhabditis bacteriophora. Despite variations in sensitivity, with S. feltiae showing greater susceptibility, both species maintained their ability to infect Galleria mellonella larvae after exposure. Exposure to Mospilan 20 SP® significantly decreased the reproductive capacity of S. feltiae (F = 443.215, p < 0.001), while H. bacteriophora showed greater resilience, especially when exposed to and Kobe 20 SP®. The ED50 values for H. bacteriophora increased over time with Kobe 20 SP® (0.46 ±0.04 at 24 h to 0.60 ±0.01 at 96 h), while Mospilan 20 SP® decreased the ED50 for S. feltiae (0.55 ±0.02 at 24 h to 0.64 ±0.03 at 96 h). The study highlights that the effects of systemic insecticides extend beyond immediate mortality, influencing reproductive potential and long-term viability, particularly for more sensitive species like S. feltiae. These findings raise important considerations for integrating EPNs into pest management strategies, especially in systems reliant on chemical pesticides. Further research is recommended to explore the broader ecological impacts of neonicotinoids on beneficial nematodes and their potential interactions with other biocontrol agents, aiming to enhance the sustainability of integrated pest management systems.

The extensive use of neonicotinoid and butenolide insecticides in horticultural systems has raised concerns about their potential effects on nontarget soil organisms, including plant-parasitic nematodes and earthworms. This study evaluates the effects of two commonly used insecticides, a neonicotinoid (acetamiprid) and butenolide (flupyradifurone), on the survival of plant pathogenic nematodes Hirschmanniella baltica , Ditylenchus laurae , and the earthworm Eisenia fetida in horticultural soils. A four-parameter Weibull model was used to analyze the survival dynamics following exposure of nematodes to one concentration of acetamiprid and Eisenia fetida to two concentrations. Both insecticides exhibited similar toxicity to earthworms, emphasizing the need for careful consideration of their use in sustainable pest management practices. These findings highlight the importance of evaluating the ecological risks of insecticides in horticulture, particularly regarding their unintended consequences on soil fauna. Further research is recommended to optimize the use of these insecticides while minimizing potential harm to beneficial soil organisms.

Root-knot nematodes Meloidogyne spp. are sedentary endoparasites that infest a wide range of plant species; they are also widely distributed, making them one of the most economically significant pests. Similarly, damage caused by Aphelenchoides fragariae can lead to substantial reductions in both crop yield and quality. This research focused on the rhizosphere of Helianthus tuberosus L. (variety Albik), grown in a Polish plantation. The experiment was conducted at the National Institute of Horticultural Research in Skierniewice, using concrete rings filled with medium sandy soil amended with 10% peat. The treatments included the following: control (no amendments), silver solution (Ag+) (120 mg/L soil), and vermicompost (Ve) (20 L of Eisenia fetida vermicompost). Each treatment was replicated four times. Compared with control, (Ve) significantly decreased the numbers of Aphelenchoides fragariae and Meloidogyne hapla, by about 48% and 31%. The application of (Ag+) led to the most significant reduction in population density in both nematode species, with A. fragariae decreasing by over 67% and M. hapla by approximately 75%.

The investigation is devoted to the analysis of the impact of organic fertilisers, in particular biochar derived from sewage sludge, on the productivity of the energy crop Miscanthus × giganteus and soil health on marginal lands. The results of long-term observations show that among organic additives, biochar demonstrates the most pronounced stabilising effect on the structure of the nematode community, although its impact on the total number of nematodes is limited. The application of biochar increased the diversity of trophic groups and modified the soil trophic network, which was dose-dependent. The experiment also revealed a significant impact of organic additives on the ecological indicators of nematode communities. In particular, the use of biochar significantly increased the Maturity Index (MI) and the Structural Index (SI), which indicates an improvement in the stability and complexity of the soil ecosystem. Reducing the number of migratory endoparasites and other plant-parasitic nematodes, such as Pratylenchus spp. was crucial in increasing the yield of M. × giganteus. The most pronounced changes were observed when biochar was applied at 10% (BD2). The field trial also assessed the impact of organic amendments on soil microbiological characteristics. Although the total number of bacteria and fungi did not change significantly, there was an increase in the number of Pseudomonas bacteria in the biochar-treated samples. This confirms the role of biochar as a stimulator of the growth of beneficial microorganisms and improvement of soil microbial activity. At the same time, the activity of dehydrogenase, which is an indicator of microbial activity, did not change significantly under the influence of additives. The test findings indicate that the addition of biochar has a beneficial effect on the yield of M. × giganteus, contributing to an increase in green mass at harvest. The impact of organic amendments was long-lasting, demonstrating the potential to increase the productivity of energy crops on marginal lands. Reducing the number of plant-parasitic nematodes, especially migratory endoparasites, was a key factor in improving yields. The outcomes of the study confirm the significance of an integrated approach to the application of organic amendments to improve soil health and increase the productivity of energy crops. The dose-dependent effects of biochar indicate the need to adapt application strategies to specific agroecosystems. Further research should focus on analysing the long-term effects of organic fertilisers on the functioning of trophic networks and microbiological processes in the soil.

Miscanthus × giganteus biomass plays a crucial role in producing renewable energy and bio-based products, supporting global sustainability objectives. However, its introduction into the European Union has made it susceptible to the ectoparasitic needle nematode Longidorus spp., which are known vectors of severe viral diseases. The aim of the presented research was to assess the effectiveness of the following soil amendments: vermicompost from Eisenia fetida and silver nanoparticles (Ag-NPs) applied to the soil with Miscanthus plants following artificial inoculation of Longidorus elongatus. A two-year experiment was conducted at the National Institute of Horticulture Research in Skierniewice using concrete rings filled with medium sandy soil amended with 10% peat. Treatments included: control (no amendments), vermicompost (4 L of E. fetida vermicompost), and Ag-NPs (60 mg/L soil). Each treatment was replicated four times. Application of both vermicompost and Ag-NPs positively influenced soil parameters and crop yield while suppressing nematode populations. Significant reductions in L. elongatus density were observed: vermicompost reduced nematode population by 80% and Ag-NPs by 90% compared to the control (15%).