Summary Soil and aquatic ecosystems continue to be impacted by environmental pollution from petroleum hydrocarbons, pesticides, polycyclic aromatic hydrocarbons (PAHs), synthetic dyes and other persistent contaminants, leading to a disruption of nutrient cycling, oxygen availability and microbial community structure. Nematodes have been employed as the primary organisms for bioremediation due to their wide distribution, varied feeding patterns and close relationships with microorganisms. This review synthesises the currently available evidence of the role of soil and aquatic nematodes in degradation of pollutants, including their interactions with hydrocarbon-degrading, PAH-degrading and herbicide-degrading microorganisms along the food chain. Bacterivorous, omnivorous and carnivorous benthic nematodes stimulate microbial respiration, enzyme activity, nutrient mineralisation and bacterial dispersal, which accelerate degradation of contaminants, including petroleum hydrocarbons, phenanthrene, prometryne and synthetic dyes. Nematode-bacteria co-culture systems can enhance degradation efficiency of contaminants in both terrestrial and marine environments and species like Steinernema feltiae and Diploscapter coronatus can serve as both bioremediators and bioindicators of environmental recovery. In this review we examine the latest developments in nematode assisted bioremediation, the environmental factors influencing their efficacy and their potential to serve as the foundation for environmentally friendly, long term remediation techniques.

Summary Trophic groups are the foundation of nematode ecological classification, providing a meaningful context for examining spatial relationships and community assembly among different species that occur in the same habitat. A trophic-based framework was implemented in this review to explore the functional contributions of nematode communities to nitrogen (N) transformations in soil ecosystems. We discuss the main underlaying mechanisms of N transformation for each trophic group including bacterivores, fungivores, herbivores, omnivores and predators, as well as the whole nematode community. Nematodes may receive their food resources from food chains as herbivores and microbivores, but not as detritivores. According to the trophic-based framework, bacterivore nematodes are main drivers of N cycles, particularly in the short term, but fungivore nematodes mainly balance immobilisation-mineralisation processes during N transformations in soil ecosystems. Evidence is increasingly confirming that whole nematode community influences N cycling. Herbivore nematodes trigger the process of N mineralisation by enriching root exudations and stimulating microbial growth via the mechanism of priming. Other trophic groups, such as bacterivores, fungivores and omnivore nematodes, release nutrients primarily as plant available forms through constant grazing on the stimulated microorganisms. Finally, predators regulate the diversity of microbial grazers, further enhancing N transformations in soil. We also highlight unexplored research areas including potentially effective roles of herbivore, omnivore and predatory nematodes in N cycling. Certain uncovered steps of the N cycle, such as N fixation, denitrification and leaching, are highlighted as requiring further research. Ultimately, we provide recommendations for future investigation to leverage the practical aspects of nematode communities for improved nutrient cycling or multifunctionality in sustainable agriculture.

Summary Root-knot nematodes of the genus Meloidogyne are major plant pathogens that induce specialised feeding sites in roots, causing severe yield losses in rice. Meloidogyne graminicola forms galls containing multinucleated giant cells that act as metabolic sinks, but the proteomic changes underlying this process remain poorly understood. Here, we present the first comprehensive proteomic analysis of rice galls induced by M. graminicola at 7 days post-inoculation using data-independent acquisition (DIA) mass spectrometry. Differential expression analysis identified over 2400 proteins with significant abundance changes between galls and non-infected roots. Gene set enrichment analysis revealed extensive reprogramming in gall tissue, including upregulation of pathways related to carbohydrate metabolism, amino acid biosynthesis, cell wall remodelling, and proteasome function, alongside suppression of immune-related proteins. Differential detection analysis highlighted gall-specific proteins involved in sucrose hydrolysis and monosaccharide transport, supporting the role of giant cells as strong metabolic sinks. Comparative analysis with RNA-seq datasets uncovered substantial post-transcriptional regulation, particularly for defence-related genes, suggesting mechanisms of translational suppression or targeted protein degradation. These findings provide novel insights into the molecular strategies employed by M. graminicola to manipulate host metabolism and immunity and underscore the added value of integrating proteomics with transcriptomic studies.

Summary Crop rotation is a widely recommended strategy for sustainable management of plant-parasitic nematodes. However, the ecological adaptability of Rotylenchulus reniformis raises questions about its long-term suppression under different cropping systems. This study evaluated how soybean and maize affect the population density and vertical distribution of R. reniformis in a tropical no-till system. Nematode densities were quantified in soybean and maize fields and compared with fallow soil across two phenological stages (80 and 140 days after planting) and two depths (0-20 and 20-40 cm). Soybean markedly increased R. reniformis densities and promoted vertical displacement from the surface to the subsurface layer over the crop cycle. Maize maintained lower densities that were statistically similar to fallow soil, although modest increases at 140 days after planting indicate that the crop does not fully suppress nematode persistence. These findings demonstrate that R. reniformis responds strongly to soybean but can persist under maize, highlighting the need for rotational strategies that consider both host suitability and depth distribution.

Summary Potato cyst nematodes cause significant yield losses in potato crops worldwide. Trap cropping with non-host solanaceous species offers a sustainable alternative to chemical control by inducing nematode hatching without supporting lifecycle completion. However, trap crop efficacy is often limited by poor establishment under nutrient-deficient conditions. Arbuscular mycorrhizal (AM) fungi, known to enhance plant growth through improved nutrient acquisition, may strengthen trap crop performance. This study investigated whether AM fungi colonise Solanum trap crops ( S. chenopodioides and S. scabrum ) and assessed their impact on Globodera pallida suppression. Both plant species were colonised by AM fungi, resulting in increased root biomass. In sterile and field soils, AM fungal inoculation significantly enhanced the ability of trap crops to reduce G. pallida populations compared to AM-free plants. Furthermore, root leachates from AM-colonised trap crops induced greater expression of the nematode hatching gene Gp-nep-1 , suggesting amplified hatch stimulation. These findings demonstrate that AM fungi improve both growth and biological efficacy of Solanum trap crops, positioning AM-enhanced trap cropping as a potential strategy for integrated G. pallida management.

Nematology is an international journal for the publication of all aspects of nematological research (with the exception of vertebrate parasitology), from molecular biology to field studies. Papers on nematode parasites of arthropods, and on soil free-living nematodes, and on interactions of these and other organisms, are particularly welcome. Research on fresh water and marine nematodes is also considered when the observations are of more general interest. Papers on nematode parasites of vertebrates are not accepted and should be submitted elsewhere. Nematology publishes full research papers, short communications, Forum articles (which permit an author to express a view on current or fundamental subjects), full communications at nematology symposia, reviews of books and other media, announcements of nematological activities and societies.

Summary The soybean cyst nematode, Heterodera glycines , is a major pest in soybean cultivation. Identifying and quantifying nematodes can be achieved through probe-based real-time PCR, and two sets of primers/probes have been developed to target H. glycines . However, we found that one set showed low species specificity, and the other showed significant variations in Ct values among H. glycines populations, potentially leading to inaccurate quantification. Therefore, for more reliable identification and quantification, we developed a novel primer/probe set based on the H. glycines mitochondrial cytochrome c oxidase subunit I gene. The novel primer/probe set amplified DNA of all tested H. glycines populations but not that of the other tested species. In addition, there were no significant differences in Ct values among the tested H. glycines populations, indicating accurate quantification across populations using a fixed standard curve. The detection sensitivity of the novel primer/probe set was higher than or comparable to that of the existing primer/probe sets. The novel primer/probe set thus facilitates reliable identification and quantification of H. glycines , supporting decision-making for the appropriate control of H. glycines .

Summary The management of waste and execution of sustainable pest control pose considerable challenges in modern agriculture. This study introduces an innovative approach using phosphate sludge-enriched compost (PSEC) and demonstrates its significant dual function of improving crop yield and controlling nematodes. PSEC, made up of 20% phosphate sludge, 70% food waste, and 10% green waste, was tested at concentrations ranging from 0% (serving as infected, non-treated control) to 100% for their impact on the physio-morphological development of tomato plants, management of Meloidogyne javanica , and improvement of soil quality, especially pH and electrical conductivity (EC). The results revealed a significant improvement in plant growth at 20% PSEC, which led to substantial increases in fresh weight (873.43%), dry weight (549%), and root weight (359%), followed by a decline at higher concentrations. Examination of biochemical variables demonstrated increased levels of chlorophyll a and b at lower concentrations (1-3%), whereas heightened PSEC concentrations initiated a strategic compromise between phenolic compounds and flavonoid contents, signifying enhanced physiological response. The 100% PSEC treatment achieved remarkable nematode control, reducing the gall index by 40% and decreasing the reproduction of M. javanica by 92%. PSEC had the ability to modify soil properties, elevating pH from 6.65 to 8.30 and EC from 83.4 to 762.67 μ S cm −1 . These results indicate that PSEC is an effective strategy for sustainable agriculture, offering simultaneous benefits in yield enhancement, pest management and soil quality improvement, while presenting a novel method for the circular economy in agriculture by transforming industrial and agricultural waste into a valuable resource for enhanced crop protection, nematode management and soil health.

Summary The stem and bulb nematode, Ditylenchus dipsaci , is a plant-parasitic nematode that causes significant losses in crop production. Management practices against plant-parasitic nematodes are commonly implemented in the soil. Brown mustard, Brassica juncea , has significant potential as an Integrated Pest Management (IPM) product against plant-parasitic nematodes like D. dipsaci , but its efficacy depends on optimising cultivation and extraction parameters. This study investigated the influence of planting time, plant part and extraction method on the profile of B. juncea ’s bioactive compound. Additionally, the ability of B. juncea to immobilise D. dipsaci in vitro was examined. Seeds were cultivated at four different times (23 September and 11 October 2022, 1 March 2023 and 17 April 2023) and the plants were separated into parts (roots, stems, leaves, flowers, and whole plant), then processed using sonication (SAE) or microwave + sonication (MSAE) extraction. Phenolic compounds and glucosinolates of extracts were analysed. Furthermore, an in vitro nematode immobility test of the extracts was carried out against D. dipsaci . Ferulic acid was identified as the predominant phenolic compound in both extraction methods, particularly in the leaves and whole plant, followed by sinapic acid in the leaves. Sinigrin and glucoraphanin were the predominant glucosinolates. The highest total glucosinolate content was found in whole plant samples from the March planting by SAE. While the extraction method did not alter the yield of bioactive compounds, it significantly impacted nematode mobility. The highest nematode immobility (mean: 76.8%) was achieved with extracts from the stems, leaves and whole plant of the autumn plantings (September/October) using the SAE method. These results provide a framework for maximising the biopesticidal potential of brown mustard, contributing to the development of effective, plant-based crop protection products.

Summary The wood-inhabiting nematodes of the family Aphelenchoididae are part of a transmission disease association of a beetle vector and pathogenic fungi that causes economic damage to forestry worldwide. In this review the bark beetle association is analysed as the tripartite symbiotic community and a part of the wood-colonising biome that includes also the infected tree community. In the biome besides of the phoresy of blue-stain fungi and nematodes by their beetle hosts, there are mutualistic interactions of fungi and bark beetles, and the parasitic relationships of nematodes with the xylobiont fungi and plant host. Using the strength of the symbiotic adaptations of partners and phylogenetic data, a hypothesis has been put forward about the origin of the symbiotic system from two ancestral microbiomes (nematode-fungus-plant and vector-fungus-plant) with three symbionts in the final biome. For the relatively little-studied relationships of the entomochoric nematodes and fungi, two experimental methods are proposed to study the questions: i ) whether the propagative generations of beetle vectored nematodes feed preferably on fungi inoculated by the same bark beetle; ii ) whether some pathogenic xylobiont fungi may be obligatory vectored by the entomochoric nematodes.