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This study aimed to elucidate the parasitic nematode infecting the bile ducts of striped catfish. A total of 1570 fish specimens, weighing between 400.5 and 899.1 g each, were examined. A parasitological analysis revealed that 607 fish samples were infected with nematodes, with typical clinical signs including swollen in both the common bile duct and gallbladder, several white cysts in the common bile ducts, and gallbladders exhibiting a dark green coloration. Examination of the common bile ducts in striped catfish revealed the presence of two distinct parasitic nematode morphotypes. Free-living nematodes were observed residing within the lumen, the central cavity, of the common bile duct. Additionally, larval nematodes were encapsulated within cysts lining the duct wall, suggesting a more chronic parasitic association. The infection rate of worms in the common bile duct was prevalent from November to April, with the most significant infection rate occurring in March (67.1%). The intensity of free-living nematode infection was the peak in March, with a mean of 6.7 ± 1.5 worm/gallbladder, and the peak level of larval nematode encapsulation was in November, with 9.4 ± 3.8 encysted larvae/common bile duct. The highest cumulative fish mortality rate was observed in February (2.1 ± 0.4%). Morphological analysis revealed the roundworms to be white and elongated with a slight narrowing at the mid-esophageal region. The mouth extended posteriorly towards the abdomen, and a well-developed, funnel-shaped esophagus was observed. Further analysis using 18S rRNA gene sequencing confirmed the identity of the parasite within the common bile duct of striped catfish as Cucullanus bourdini. [ABSTRACT FROM AUTHOR]

ABSTRACT Parasites may suppress the immune function of infected hosts using microRNAs (miRNAs) to prevent protein production. Nonetheless, little is known about the diversity of miRNAs and their mode(s) of action. In this study, we investigated the effects of infection by a parasitic lungworm (Rhabdias pseudosphaerocephala) on miRNA and mRNA expression of its host, the invasive cane toad (Rhinella marina). To investigate the cane toad's innate and adaptive immune response to this parasite, we compared miRNA and mRNA expression in naïve toads that had never been infected by lungworms to toads that were infected with lungworms for the first time in their lives, and toads that were infected the second time in their lives (i.e., had two consecutive infections). In total, we identified 101 known miRNAs and 86 potential novel miRNAs. Compared to uninfected and single‐infection toads, multiple‐infection animals drastically downregulated three miRNAs. These miRNAs were associated with gene pathways related to the immune response, potentially reflecting the immunosuppression of cane toads by their parasites. Infected hosts did not respond with substantially differential mRNA transcription; only one gene was differentially expressed between control and single‐infection hosts. Our study suggests that miRNA may play an important role in mediating host–parasite interactions in a system in which an ongoing range expansion by the host has generated substantial divergence in host–parasite interactions. [ABSTRACT FROM AUTHOR]

A study was conducted in the mountains of Magoebaskloof, Limpopo Province, where oak trees grow along the banks of the Broederstroom River. This study revealed that 22 nematode genera were associated with oak trees (Quercus robur). The most frequently occurring nematodes were Aphelenchus sp. (100%) and Plectus sp. (100%), followed by Helicotylenchus sp. (90%). This study examined the relationship between nematodes and the physicochemical properties of the soil using Pearson correlation. It uncovered that the organic matter content (OMC) had a negative correlation with the number of Panagrolaimus sp. (r = −0.770) and Hemicycliophora sp. (r = −0.674). Conversely, the sand percentage positively correlated (r = 0.695) with the number of Hemicycliophora sp. The clay content of the soil showed a positive correlation (r = 0.617) with the number of Ditylenchus. Soil pH demonstrated a significant negative correlation with Acrobeloides sp. (r = −0.877). The canonical correspondence analysis (CCA) explained 63.3% of the relationship between nematodes and soil physicochemical properties. The CCA results indicated that Ditylenchus exhibited a positive correlation with OMC, while the Panagrolaimus and Hemicycliophora species showed a negative correlation with OMC. The results indicated that none of the soil sample sites were under stress. The soil food web analysis revealed that most soil samples were nutrient-enriched with a low C/N ratio. In conclusion, this study revealed that oak trees harbor a high diversity of plant-parasitic and free-living nematodes. The results suggest that soil nematodes, particularly free-living bacterivores, such as Panagrolaimus, can indicate organic matter content in the soil. [ABSTRACT FROM AUTHOR]

Bacterivorous nematodes are important grazers in the soil micro‐food web. Their trophic regulation shapes the composition and ecosystem services of the soil microbiome, but the underlying population dynamics of bacteria and archaea are poorly understood. We followed soil respiration and 221 dominant bacterial and archaeal 16S rRNA gene amplicon sequencing variants (ASVs) in response to top‐down control by a common bacterivorous soil nematode, Acrobeloides buetschlii, bottom‐up control by maize litter amendment and their combination over 32 days. Maize litter amendment significantly increased soil respiration, while A. buetschlii addition caused an earlier peak in soil respiration. Underlying bacterial and archaeal population dynamics separated into five major response types, differentiating in their temporal abundance maxima and minima. In‐depth analysis of these population dynamics identified a broad imprint of A. buetschlii grazing on dominant bacterial (Acidobacteriota, Bacteroidota, Gemmatimonadota, Pseudomonadota) and archaeal (Nitrososphaerota) ASVs. Combined bottom‐up control by maize litter and top‐down control by A. buetschlii grazing caused a succession of soil microbiota, driven by population changes first in the Bacteroidota, then in the Pseudomonadota and finally in the Acidobacteriota and Nitrososphaerota. Our results are an essential step forward in understanding trophic modulation of soil microbiota and its feedback on soil respiration. [ABSTRACT FROM AUTHOR]

Summary Two horses kept on different farms at a geographical distance of 150 km were presented with acute neurological dysfunction. Ante‐mortem diagnostic tests including bloodwork, CT scan and cerebrospinal fluid analysis did not provide a diagnosis in either case. Due to rapid deterioration, both horses were euthanised shortly after admission. Postmortem histopathological examination revealed granulomatous meningoencephalitis with intralesional nematodes that were morphologically identified as Halicephalobus gingivalis. This is the first documentation of central nervous system infestation by H. gingivalis in horses residing in Belgium, emphasising the importance of considering aberrant parasitic migration in the differential diagnosis of acute neurological dysfunction. [ABSTRACT FROM AUTHOR]

In the present study, the DNA barcoding of the nematode parasite infecting Ompok bimaculatus and Nemacheilus anguilla fish species was carried out in Barvi Reservoir, Maharashtra. To ascertain the taxonomic status of these nematode parasites, an 18S gene marker was used. Accurate identification of fish parasites is essential to formulate preventive strategies and to study host–environment relations. The present study did barcoding of the nematode parasites of the fishes caught from the Barvi Reservoir using the nuclear 18S rDNA (SSU) sequence. The nuclear 18S rDNA (SSU) was amplified into two overlapping amplicons and sequenced to identify the species based on the sequence similarity with the NCBI GenBank database. The present study sequences (both fragments) showed 98% similarity with the species of Eustrongylides. The average genetic distance value between the present study sample and species of Eustrongylides was 0.003. In the phylogenetic tree also, the sequence was clustered with the species of Eustrongylides with significant bootstrap values. The present study identified the nematode parasite of the fish caught from the Barvi Reservoir, as species of Eustrongylides. The species‐level identification could not be possible due to the insufficient/lack of reference sequences in the database. It indicates the knowledge gap concerning the species‐specific molecular markers for nematode parasites of the fish. [ABSTRACT FROM AUTHOR]

Background: Parascaris spp. represent a significant threat to equine health worldwide, particularly in foals. The long-term survival of parasites in the host necessitates persistent modulation of the host immune response. Intercellular communication achieved through the exchange of molecules via extracellular vesicles (EVs) released from the parasite could be a crucial factor in this regard. This study aimed to isolate and characterize EVs released by adult male and female Parascaris worms and conduct a proteomic analysis to identify sex-specific proteins and potential immunomodulatory factors. Methods: Live adult Parascaris worms were collected, and EVs were isolated from spent culture media using differential ultracentrifugation. Nanoparticle tracking analysis and transmission electron microscopy confirmed the size, concentration, and morphology of the isolated EVs. Proteins within the isolated EVs were analyzed using mass spectrometry-based proteomics (LC–MS/MS). Results: Proteomic analysis revealed a total of 113 proteins in Parascaris EVs, with several proteins showing homology to known helminth exosome proteins and exhibiting immunomodulatory functions. Sex-specific differences in EV protein composition were observed, with a distinct abundance of C-type lectins in female EVs, suggesting potential sex-specific roles or regulation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed metabolic pathways shared between male and female Parascaris EVs, as well as differences in signal transduction, and cell growth and death pathways, indicating sex-specific variations. Conclusions: These findings imply that Parascaris EVs and their protein cargo are complex. This data potentially opens avenues for discovering innovative approaches to managing and understanding helminth infection. [ABSTRACT FROM AUTHOR]

Ageratum conyzoides L. is native to Tropical America, and it has naturalized in many other tropical, subtropical, and temperate countries in South America, Central and Southern Africa, South and East Asia, Eastern Austria, and Europe. The population of the species has increased dramatically as an invasive alien species, and it causes significant problems in agriculture and natural ecosystems. The life history traits of Ageratum conyzoides, such as its short life cycle, early reproductive maturity, prolific seed production, and high adaptive ability to various environmental conditions, may contribute to its naturalization and increasing population. Possible evidence of the molecules involved in the defense of Ageratum conyzoides against its natural enemies, such as herbivore insects and fungal pathogens, and the allelochemicals involved in its competitive ability against neighboring plant species has been accumulated in the literature. The volatiles, essential oils, extracts, residues, and/or rhizosphere soil of Ageratum conyzoides show insecticidal, fungicidal, nematocidal, and allelopathic activity. The pyrrolizidine alkaloids lycopsamine and echinatine, found in the species, are highly toxic and show insecticidal activity. Benzopyran derivatives precocenes I and II show inhibitory activity against insect juvenile hormone biosynthesis and trichothecene mycotoxin biosynthesis. A mixture of volatiles emitted from Ageratum conyzoides, such as β-caryophyllene, β-bisabolene, and β-farnesene, may work as herbivore-induced plant volatiles, which are involved in the indirect defense function against herbivore insects. Flavonoids, such as nobiletin, eupalestin, 5′-methoxynobiletin, 5,6,7,3′,4′,5′-hexamethoxyflavone, and 5,6,8,3,4′,5′-hexamethoxyflavone, show inhibitory activity against the spore germination of pathogenic fungi. The benzoic acid and cinnamic acid derivatives found in the species, such as protocatechuic acid, gallic acid, p-coumaric acid, p-hydroxybenzoic acid, and ferulic acid, may act as allelopathic agents, causing the germination and growth inhibition of competitive plant species. These molecules produced by Ageratum conyzoides may act as defense molecules against its natural enemies and as allelochemicals against neighboring plant species, and they may contribute to the naturalization of the increasing population of Ageratum conyzoides in new habitats as an invasive plant species. This article presents the first review focusing on the defense function and allelopathy of Ageratum conyzoides. [ABSTRACT FROM AUTHOR]

Patterns of lineal descent play a critical role in the development of metazoan embryos. In eutelic organisms that generate a fixed number of somatic cells, invariance in the topology of their cell lineage provides a powerful opportunity to interrogate developmental events with empirical repeatability across individuals. Studies of embryonic development using the nematode Caenorhabditis elegans have been drivers of discovery. These studies have depended heavily on high-throughput lineage tracing enabled by 4D fluorescence microscopy and robust computer vision pipelines. For a range of applications, computer-aided yet manual lineage tracing using 4D label-free microscopy remains an essential tool. Deep learning approaches to cell detection and tracking in fluorescence microscopy have advanced significantly in recent years, yet solutions for automating cell detection and tracking in 3D label-free imaging of dense tissues and embryos remain inaccessible. Here, we describe embGAN, a deep learning pipeline that addresses the challenge of automated cell detection and tracking in label-free 3D time-lapse imaging. embGAN requires no manual data annotation for training, learns robust detections that exhibits a high degree of scale invariance, and generalizes well to images acquired in multiple labs on multiple instruments. We characterize embGAN's performance using lineage tracing in the C. elegans embryo as a benchmark. embGAN achieves near–state-of-the-art performance in cell detection and tracking, enabling high-throughput studies of cell lineage without the need for fluorescent reporters or transgenics. [ABSTRACT FROM AUTHOR]

An approximately 1.5‐year‐old mixed breed heifer was presented for evaluation and treatment due to ocular pain affecting the right eye secondary to a live nematode within the anterior chamber. Ophthalmic examination revealed marked blepharospasm, evidence of chronic keratitis, uveitis, and a single, white, approximately 2.5 cm long, 0.5 mm thick, living parasite. The heifer underwent general anesthesia, and the parasite was removed using passive aqueous humor outflow following a stab incision into the anterior chamber. Twenty‐four hours after removal of the intraocular parasite, the heifer displayed a significant improvement in ocular comfort, corneal edema, and uveitis. The nematode was identified via genetic analyses as Parafilaria bovicola, a filarial parasite of cattle. The heifer was discharged 5 days following nematode removal with a marked improvement in all ocular signs and apparently normal vision. To the authors' knowledge, there are no previous reports of confirmed intraocular filariosis caused by P. bovicola in the veterinary literature, nor are there reports detailing surgical removal of intraocular parasites in bovids. [ABSTRACT FROM AUTHOR]

Parasitic otitis is an inflammatory process that can affect the external to internal cattle ear, causing discomfort in animals, impairing performance, and even leading to animal death. The infection was initially associated with nematodes of the Rhabditis genus in tropical and subtropical regions. Currently, the nematode species described as associated with bovine otitis are Metarhabditis costai, Metarhabditis freitasi, and, more recently, M. blumi. It is worth highlighting that there is still a lack of robust information regarding the morphological details, ultrastructural aspects, and molecular biology data of these species. The Metarhabditis genus is composed of seven species and two more have recently been added. The objective of this study is to update the morphological data using advanced microscopy techniques to emphasize and clarify the main morphological differences between three species of Metarhabditis currently associated with parasitic otitis. Samples of inflammatory exudate were collected from four adult female Gir cattle (Bos taurus indicus) on a farm in Itabira, Minas Gerais state, Brazil. Specimens were analyzed using light microscopy and scanning electron microscopy. Two species, M. costai and M. freitasi, were morphologically identified, consistent with previous reports. Scanning electron microscopy revealed new structural characteristics of the nematode species involved in parasitic otitis compared with M. blumi obtained from the CGC Center. Significant differences were observed in the male posterior region, bursa, and tail. Molecular analysis was conducted to differentiate these three species, and it was observed that the species first associated with otitis formed distinct clusters compared to M. blumi. However, it is important to note that further studies are needed to genetically characterize species of the Metarhabditis genus. [ABSTRACT FROM AUTHOR]

Zoo conditions are unique for reindeer, since domestic reindeer are not kept in captive facilities like cattle. In the zoo, reindeer are usually surrounded by many different animals that they would never encounter naturally. Thus, they might be infected with new helminths. Numerous petting zoos raise concerns about the safety of tactile interactions for human visitors. Our study is the first large-scale one. Qualitative and quantitative fecal analyses were carried out for 233 reindeer distributed over 50 Russian zoos according to the National Standard of the Russian Federation (GOST R 54627-2011) Ruminant animals—Methods of Laboratory Helminthological Diagnostics. Where possible, DNA analyses of helminths were performed targeting internal transcribed spacer region. As a result, F. hepatica, Paramphistomum sp., Moniezia sp. (including M. expansa), gastrointestinal strongylids (including Nematodirus spp.), Dictyocaulus sp., E. rangiferi, Trichuris sp., and Capillaria sp. were found in 106 (45%) zoo reindeer. All these helminths were previously reported in reindeer and pose no direct danger for humans. The intensity of invasions was mostly low. Fecal examination might be considered as an indirect method for mange diagnostics, as Chorioptes and Demodex mites were found in reindeer fecal samples. The latter may represent a novel species of mite specific for reindeer. [ABSTRACT FROM AUTHOR]

Abdominal angiostrongyliasis (AA) is a zoonotic and severe parasitic infection caused by Angiostrongylus costaricensis. AA is currently diagnosed by the observation of A. costaricensis-compatible structures in biopsies or the detection of antibodies in serological tests. However, molecular methods targeting homologous sequences of A. costaricensis have not been designed before, and therefore, an HRM-coupled qPCR was developed to detect the internal transcribed spacer 1 (ITS1) of the parasite. The present assay successfully amplified DNA of A. costaricensis obtained from different hosts and identified slight sequence differences through the HRM analysis. The detection limit of the HRM-qPCR was 0.00036 ng/µL, 1.0 ng/µL, and 0.1 ng/µL when A. costaricensis DNA was diluted in nuclease-free water, whole blood, and sera, respectively, which highlights its potential use for cell-free DNA detection. Moreover, the reaction did not cross-amplify DNA of Angiostrongylus cantonensis, Strongyloides stercoralis, and other nematodes, thus emphasizing its specificity. Additionally, the assay tested positive in formalin-fixed paraffin embedded biopsies with visible A. costaricensis adults or eggs, but not in samples without evident parasites or a low number of larvae, which suggests that the reaction is useful for confirming the presence of the nematode in clinical samples. Finally, DNA of sera from patients with AA was evaluated with the HRM-qPCR but none tested positive, possibly due to long storage periods of the samples which could have led to cfDNA degradation. These results indicate that this assay may be useful in the confirmation of AA and its prospection for cell-free DNA detection protocols. [ABSTRACT FROM AUTHOR]

Infections of endoparasites in primates in natural habitats are highly prevalent and can cause disease, reduce health quality, and disrupt their life. This study investigated endoparasites prevalence value in the endangered Javan gibbon (Hylobates moloch) in Citalahab Forest, Gunung Halimun Salak National Park, Indonesia, from June to August 2022 by collected fecal samples (N = 10) and analyzed it using floatation methods. As a result, we found five genera of nematodes Trichuris trichiura (10% egg worm prevalence, Oesophagostomum spp. (50%), Trichostrongylus spp. (60%), Ancylostoma spp. (80%), and Strongyloides spp. (100%). The prevalence value of the worms in the larvae stage of Trichostrongylus spp. 20% and Strongyloides spp. 70%. Nematode infection status successively is Strongyloides spp., which is, frequently; Trichostrongylus spp. and Ancylostoma spp., which is, often; Oesophagostomum spp. and Trichuris trichiura which is, occasionally. Four species of nematode were found in both ages, and only Trichuris trichiura was found in one adolescent individual. The threat posed by this parasite deserves attention; further research is needed to fill the gap in our knowledge of their pathogenicity and transmission in Javan gibbon. [ABSTRACT FROM AUTHOR]

Native turkeys kept as domestic bird in rural environments can be infected with bacterial, viral and parasitic agents. Parasites affect health and production of turkeys and cause economic loss. Capillaria spp. and Heterakis spp. are the major helminths reported to be highly pathogenic for turkeys in both deep-litter systems and free-range systems. The most important role of H. gallinarum is its capability of transferring the protozoan Histomonasmeleagridis, responsible for infectious enterohepatitis in fowls. Hence the characterisation of species is necessary to adopt proper management and control measures. The present report documents the morphological identification of nematodes collected during postmortem examination of turkeys in a small holder farm at Thrissur.A markedly dilated caecum with severe catarrhal exudates was observed. The examination of intestinal contents revealed parasitic ova along with adult worms. The recovered adult worms were identified as Baruscapillaria obsignata and Heterakis gallinarum. Faecal sample examination of live birds in the farm also revealed mixed infections. The birds with infection were advised treatment with pyrantel pamoate at a dose rate of 7 mg/kgper orally once. [ABSTRACT FROM AUTHOR]

• MgONPs were synthesized through green approach using trichoderma fungus. • Myco-synthesized NPs exhibited strong nematicidal activity. • Soil application of NPs improved plant growth under nematode infection. • Soil application of NPs reduced nematode population and development. Meloidogyne incognita is believed to be the most devastating pest causing severe damage to crops, and hence, innovative and effective means of controlling the nematode is the need of the day. The focus of the current study is to devise an effective and innovative myco-fabrication of MgO nanoparticles (NPs) along with melatonin for efficient management of M. incognita infecting tomatoes. Fungal extracts were used to synthesize the myco-fabricated NPs through a green synthesis pathway and were verified using different spectroscopic means. The nanoparticles exhibited appreciable nematicidal potential, such as drastic egg hatch inhibition and juvenile mortality under in vitro assays. Evaluation of NPs and melatonin in planta, alone or combined form, was investigated on tomato plants already inoculated with M. incognita. The alterations in the nematode population on roots of plants as well as in soil, growth parameters, and biochemical attributes of plants were recorded. A significant reduction in nematode population was revealed on the application of melatonin and myco-fabricated nanoparticles, hence exhibiting an improvement in the plant's biochemical (glutathione, phenolic, flavonoid, and antioxidant enzymes) and growth parameters. A synergistic impact was shown on the combined application of the treatments. Furthermore, an enhancement in the expression as well as activities of antioxidant enzymes was also observed. Increased resistance of plants against nematodes resulted in connection with the improved antioxidant status of plants due to this combined treatment. The significantly improved growth of plants under M. incognita stress conditions reveals the potential of the proposed treatments having synergistic interaction to manage phyto-parasitic nematodes effectively. This presents innovative means of agricultural biotechnologies that have the potential to contribute to the efficient management of nematodes infecting plants. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes are a major problem for horticultural production, causing significant economic losses. Chemical nematicides are a common nematode control strategy but can negatively impact the environment and human health. In this review, we provide an overview of the use of fungi for the biological control of plant-parasitic nematodes in horticultural crops. Fungal bio-control represents an alternative, environmentally friendly strategy for managing nematodes. The use of fungi for the bio-control of nematodes has gained increasing attention due to the potential benefits of selectivity, sustainability, and long-term control. Here, we discuss the different types of fungi used for nematode management, the mechanisms of their action, the advantages and limitations of using fungi for bio-control, and the factors affecting their efficacy. Additionally, we provide several case studies of fungal bio-control against root-knot, cyst, and lesion nematodes in horticultural crops. The review concludes with a discussion of future directions and research recommendations for implementing fungal bio-control in horticultural crops. [ABSTRACT FROM AUTHOR]

AbstractThe increasing public demand to avoid the use of synthetic pesticides and fertilizers in agricultural production systems, causing serious environmental damages, has challenged industry to develop new and effective solutions to manage and control phytopathogens. Biopesticides, particularly microbial-based biopesticides, are a promising new alternative with high biodegradability, specificity, suitability for incorporation into integrated pest management practices, low likelihood of resistance development, and practically no known human health risks. However: expensive production methods, narrow action spectra, susceptibility to environmental conditions, short shelf life, poor storage stability, legislation registry constraints, and general lack of knowledge are slowing down their adoption. In addition to regulatory framework revisions and improved training initiatives, improved preservation methods, thoughtfully designed formulations, and field test validations are needed to offer new microbial- and nematode-based biopesticides with improved efficacy and increased shelf-life. During the last several years, substantial advancements in biopesticide production have been developed. The novelty part of this review written in 2023 is to summarize (i) mechanisms of action of beneficial microorganisms used to increase crop performance and (ii) successful formulation including commercial products for the biological control of phytopathogens based on microorganisms, nematode and/or metabolites. [ABSTRACT FROM AUTHOR]

We report a case of infection with the zoonotic nematode Gongylonema sp. in a 24-year-old woman from Varna, Bulgaria. Two days before seeking medical attention, the patient had noticed a filamentous mass in her buccal mucosa that migrated when touched with the tongue. She manually removed a thread-like worm from the mucosa near her lower lip. Albendazole was prescribed for three days. The patient had no history of travelling abroad or contact with animals. To our knowledge, this is the sixth case that has been reported in the country. [ABSTRACT FROM AUTHOR]

The Old-World bollworm, Helicoverpa armigera (Lepidoptera: Noctuidae), is a significant threat to crops worldwide and has become resistant to traditional synthetic insecticides. The present study investigated the pathogenicity of the entomopathogenic fungi (EPF) Metarhizium robertsii (Hypocreales: Clavicipitaceae) strain WG-04 or Beauveria bassiana (Hypocreales: Cordycipitaceae) strain WG-10, and an entomopathogenic nematode (EPN) species Heterorhabditis bacteriophora against the second and fourth instar larvae of H. armigera. Both fungal species and H. bacteriophora were evaluated, singly or in combination. After 24 and 48 h post-application of the fungal spores (106 spores/mL), H. bacteriophora was introduced at a rate of 50 infective juveniles/mL, and mortality was observed at 3-, 5-, and 7-days post-treatment. Adult emergence, egg hatching, and percentage pupation were recorded. The integration of both types of biocontrol agents exhibited additive and synergistic interactions in larval stages, and enhanced mortality was recorded when EPF was used in combination with the nematodes. In the individual application of all three biocontrol agents alone, the order of efficacy was H. bacteriophora > B. bassiana > M. robertsii; however, in joint treatments, the increase in mortality and decrease in percentage egg hatching, pupation, and adult emergence was determined to be directly linked to the exposure period of the H. bacteriophora. The results of this study suggest that combining H. bacteriophora with EPF could provide a solid foundation for an economically viable method for managing H. armigera larvae in chickpea fields. [ABSTRACT FROM AUTHOR]

Invasive plants are capable of homogenizing both aboveground and belowground biota and, along with climate change, are recognized as one of the biggest threats to global biodiversity. Soil nematode communities reflect the surroundings they inhabit and are therefore frequently employed as biological indicators of soil condition. In this study, soil properties and nematode communities in Carpathian beech forest floor covered by dense vegetation of invasive Impatiens parviflora (small balsam) were investigated over two vegetation seasons. We assumed that the spread of invasive I. parviflora could influence soil fauna through litter accumulation when established and could also change several soil properties, consequently altering soil nematode communities. A total of 52 nematode species were found in the soil samples. The mean number of species varied from 18 to 31, but did not significantly differ between invaded and uninvaded plots across all sampling dates. However, redundancy analysis indicated that the nematode community in plots with small balsam differed significantly from that in uninvaded plots, reflecting different proportions of genera in the two communities. Invasion by small balsam significantly enhanced the relative abundance of bacterivores, whereas it decreased the abundance of plant parasites and root-fungal feeders, mainly in the spring and summer season. Ordination of nematode species along the structure index and enrichment index trajectories revealed a maturing food web, low to moderately disturbed in the I. parviflora invaded soils as well as in uninvaded forest plots. Decomposition channels of soil food webs in both plots were balanced and fungal–bacterial mediated, although low values of the channel index suggested prevailing bacterial decomposition. Our study reveals that the expansion of I. parviflora moderately influenced the composition of nematode communities and the soil food web, increased soil nitrogen, carbon and C/N ratio, but did not modify soil acidity. [ABSTRACT FROM AUTHOR]

Exsheathment is crucial in the transition from free-living to parasitic phase for most strongyle nematode species. A greater understanding of this process could help in developing new parasitic control methods. This study aimed to identify commonalities in response to exsheathment triggers (heat acclimation, CO2 and pH) in a wide range of species (Haemonchus contortus, Trichostrongylus spp., Cooperia spp., Oesophagostomum spp., Chabertia ovina, and members of the subfamily Ostertagiinae) from sheep, cattle and farmed deer. The initial expectation of similarity in pH requirements amongst species residing within the same organ was not supported, with unexpected pH preferences for exsheathment of Trichostrongylus axei, Trichostrongylus vitrinus, Trichostrongylus colubriformis and Cooperia oncophora. We also found differences between species in their response to temperature acclimation, with higher exsheathment in response to heat shock observed for H. contortus, Ostertagia ostertagi, T. axei, T. vitrinus and Oesophagostomum sikae. Furthermore, some species showed poor exsheathment under all experimental conditions, such as Cooperia curticei and the large intestinal nematodes C. ovina and Oesophagostomum venulosum. Interestingly, there were some significant differences in response depending on the host from which the parasites were derived. The host species significantly impacted on the exsheathment response for H. contortus, Teladorsagia circumcincta, T. vitrinus and T. colubriformis. Overall, the data showed variability between nematode species in their response to these in vitro exsheathment triggers, highlighting the complexity of finding a common set of conditions for all species in order to develop a control method based on triggering the exsheathment process prematurely. [ABSTRACT FROM AUTHOR]

I summarize my recent theorizing on orientation and navigation across life. Organisms use navigational servomechanisms working with oscillators to get to goals. Navigational servomechanisms track errors from the best direction of travel and initiate action to correct the error. They work with endogenously generated action patterns, oscillations produced by oscillators, to adjust the course of travel. The theme applies to all scales of life from micrometers to thousands of kilometers. Servomechanisms and oscillators also characterize some other domains of cognition. [ABSTRACT FROM AUTHOR]

Background: Nematodes are the most abundant and diverse metazoans on Earth, and are known to significantly affect ecosystem functioning. A better understanding of their biology and ecology, including potential adaptations to diverse habitats and lifestyles, is key to understanding their response to global change scenarios. Mitochondrial genomes offer high species level characterization, low cost of sequencing, and an ease of data handling that can provide insights into nematode evolutionary pressures. Results: Generally, nematode mitochondrial genomes exhibited similar structural characteristics (e.g., gene size and GC content), but displayed remarkable variability around these general patterns. Compositional strand biases showed strong codon position specific G skews and relationships with nematode life traits (especially parasitic feeding habits) equal to or greater than with predicted phylogeny. On average, nematode mitochondrial genomes showed low non-synonymous substitution rates, but also high clade specific deviations from these means. Despite the presence of significant mutational saturation, non-synonymous (dN) and synonymous (dS) substitution rates could still be significantly explained by feeding habit and/or habitat. Low ratios of dN:dS rates, particularly associated with the parasitic lifestyles, suggested the presence of strong purifying selection. Conclusions: Nematode mitochondrial genomes demonstrated a capacity to accumulate diversity in composition, structure, and content while still maintaining functional genes. Moreover, they demonstrated a capacity for rapid evolutionary change pointing to a potential interaction between multi-level selection pressures and rapid evolution. In conclusion, this study helps establish a background for our understanding of the potential evolutionary pressures shaping nematode mitochondrial genomes, while outlining likely routes of future inquiry. [ABSTRACT FROM AUTHOR]

• Extracted root protein from resistant and susceptible tobacco genotype at 60 DAI of nematode infection. • 2DE and in-solution digested proteins analyzed by RPLC-MS/MS to identify the unknown proteins. • Comparative proteomics revealed RFK1 and RPP 13 like candidate genes exclusively present in resistant genotype. • Out of 306 proteins, 79 proteins were up-regulated and 51 proteins were down-regulated. • These candidate genes can be exploited for the development to resistant crop against nematode disease. Root knot nematode (RKN) is an obligate endoparasitic pest of many vegetable, fruits, non-food cash crops etc. It causes more economic losses in terms of production and productivity worldwide. A range of management strategies including synthetic nematicides are available which can be harmful to human health, environment, wildlife, beneficial organisms and may induce resistance in plant populations. Therefore, identification of resistant gene is an alternative strategy to improve the crop either through breeding or by transgenic technology. In present investigation, an attempt was made to identify the candidate genes resistant to root knot nematode through proteomics approach. Comparative proteome was executed using RKN resistant ABT-10 and susceptible A-119 genotype. Proteomics was performed on nematode-challenged root tissue using 2D gel electrophoresis, in-solution trypsin digestion, and reverse phase liquid chromatography mass spectrometry. A total of 306 proteins were identified of which 79 proteins were up-regulated, 51 were down-regulated and 176 proteins showed no significant expression in resistant genotype. Out of 51 up-regulated proteins, two genes namely LRR Receptor-Like Serine/Threonine-Protein Kinase RFK1 and Putative Disease Resistance RPP13-Like Protein were identified in RKN resistant genotype. In addition to these two genes, RT-PCR analysis showed that three additional genes—Putative Wall-Associated Receptor Kinase-Like 11, Alpha-mannosidase, and TMV Resistance Protein N-Like gene—had significantly higher gene expression levels in the resistant root sample, exhibiting 14.89, 9.95, and 6.81 fold expression, respectively. The identified candidate genes can be exploited further for development of nematode resistant genotype in vegetables as well as other field crops through transgenic approaches. [ABSTRACT FROM AUTHOR]

Simple Summary: There are growing concerns about wildlife and livestock interactions and the impacts of those interactions on the sustainability of livestock. One of those concerns is the spillover of wildlife pathogens, including helminths, into livestock. This concern will likely become realized as the demand for free-range animal products increases. One such helminth with spillover potential is the eyeworm Oxyspirura petrowi. This eyeworm is common in many wild birds, and particularly common in Northern bobwhite quail. Related helminths are already commonly found in poultry raised in free-range conditions in developing nations. The purpose of this research was to investigate the lethality of fenbendazole, a widely available drug for treating parasites, to these eyeworms. The lethality estimates were similar to estimates of lethality to other roundworm parasites. However, studies that have investigated concentrations in host blood following administration of the drug indicate that it does not stay in the system long enough to achieve elimination of the parasite after a single dose. This indicates that in order to effectively treat eyeworm, fenbendazole must be delivered in a repeated or continuous manner. Oxyspirura petrowi is a heteroxenous nematode that infects the harderian gland and other ocular tissues in birds. High-intensity infections often cause damage to the infected tissues. Due to the nature of the infection sites, treatment of O. petrowi in these hosts can be difficult. Fenbendazole (FBZ) is a common anthelmintic used to treat birds for helminth infections; however, little information exists as to the efficacy of the drug on O. petrowi infections. The present study aims to estimate lethal concentrations of FBZ to O. petrowi. Adult O. petrowi were maintained in vitro and exposed to doses of 5, 50, 100, and 200 µM concentrations of FBZ and included both negative and vehicle controls. Exposure lasted 7.5 days and lethality was determined for each treatment. Negative and vehicle controls did not differ, and both had 75% survival at the end of the treatment period. The percentage survivorship in ascending order of concentration, corrected for the controls, was 66.67%, 44.44%, 33.33%, and 0%. LC10, LC50, and LC90 estimates were 7.5 ± 0.26, 49.1 ± 1.69, and 163.2 ± 5.63 µM, respectively. In the context of known pharmacokinetics of FBZ in birds, a single oral dose of FBZ can achieve exposure levels that are lethal to O. petrowi, but the drug does not stay in the system long enough. Thus, treatment of O. petrowi infections will require multiple oral doses over several days. [ABSTRACT FROM AUTHOR]

A survey was conducted in the agricultural fields of mustard of Haridwar district, Uttarakhand, India, where a heavy population of Zeldia was recovered. The morphological, molecular, and phylogenetic characterization confirmed the nematode as Zeldia punctata. The phylogenetic analysis based on 18 and 28S rDNA placed the studied population of Z. punctata close to other populations of the same species. The principal component analysis (PCA) data revealed the high intraspecific and interspecific variations between the populations of Zeldia punctata from different geographical regions. The result indicated a variation between the Indian populations of Z. punctata. Additionally, the selected ecological factors indicated an impact of EC, temperature, and phosphorus on Z. punctata during the flowering and podding time of mustard crops in India. However, the PCA revealed no effect of ecological factors on the nematode diversity indices. In conclusion, Z. punctata, with its high individual numbers on mustard, may affect crop production due to activating the bacterial community of the soil and less space for plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) are well-known biocontrol agents to control both above- and below-ground insect pests. EPNs can also control plant parasitic nematodes by releasing allelochemicals through symbiotic bacteria present in their guts. This study aimed to evaluate the bio-efficacy of a novel powder formulation comprising of infective juveniles (IJs) of a heat-tolerant indigenous EPN species of India, Steinernema abbasi, against subterranean termites (Odontotermes obesus) in wheat and chickpea fields. The bioefficacy of test formulation in field study for three rabi seasons (2020-2023) in wheat and chickpea grown in field heavily infested with subterranean termites decreased the plant damage from termite attack, monitored as relative number of infested tillers in wheat and infested plants in chickpea fields. The reduced damage in test crops caused by termites increased growth, yield attributes and yield of test crops. This present research validated the prepared formulation's potential as a biopesticide ideal for organic farming and integrated pest management practices. [ABSTRACT FROM AUTHOR]

Abnormal blood coagulation is a major health problem and natural anticoagulants from blood-feeding organisms have been investigated as novel therapeutics. NAPc2, a potent nematode-derived inhibitor of coagulation, has an unusual mode of action that requires coagulation factor Xa but does not inhibit it. Molecular dynamics simulations of NAPc2 and factor Xa were generated to better understand NAPc2. The simulations suggest that parts of NAPc2 become more rigid upon binding factor Xa and reveal that two highly conserved residues form an internal salt bridge that stabilises the bound conformation. Clotting time assays with mutants confirmed the utility of the salt bridge and suggested that it is a conserved mechanism for stabilising the bound conformation of secondary structure-poor protease inhibitors. [ABSTRACT FROM AUTHOR]

The aim of this study is to identify plant-parasitic nematodes molecularly and morphologically in wheat (Triticum spp.) fields in the Eastern Anatolia Region (Türkiye) between 2017-2019. For this purpose, a total of 258 soil samples were collected from 7 provinces (Erzincan, Elazığ, Erzurum, Iğdır, Kars, Malatya, and Sivas) in the Eastern Anatolia Region. Nematodes were morphologically identified using a light microscope at the genus (some of them species) level. DNA extraction was performed and PCR products were used to DNA sequencing and nucleotide analysis for 28S ribosomal DNA region by comparing the results with the database. According to the obtained data, a total of 20 genera and 7 species belonging to 2 orders and 9 families were identified: H. digonicus Perry, 1959; H. canadensis Waseem, 1961; H. vulgaris Yuen, 1964 (Nematoda: Hoplolaimidae); Ditylenchus myceliophagus Goodey, 1958 (Nematoda: Anguinidae); Amplimerlinius macrurus (Goodey, 1932) (Nematoda: Dolichodoridae); Scutylenchus quadrifer (Andrassy, 1954); (Nematoda: Dolichodoridae), and Pratylenchoides alkani Yüksel, 1977 (Nematoda: Pratylenchidae). H. vulgaris was identified at the species level using molecular techniques. The rates of presence of economically important plant parasitic nematodes were determined as 73%, 43%, 36%, 33% and 28% for Ditylenchus spp., Pratylenchus spp., Aphelenchus spp., Xiphinema spp. and Helicotylenchus spp. respectively. It is thought that the results obtained will help to plan nematode control methods in the region. [ABSTRACT FROM AUTHOR]

Horticultural and musaceous crops are of great economic importance in Ecuador. Although there are studies on the association of phytopathogenic nematodes and the damage they cause, little research has been done on the diversity and composition of nematodes in these crops. The present study evaluates the diversity, composition and abundance of the nematode community related to soil physicochemical characteristics, reports Shannon H' diversity and nematode community structure, based on their trophic groups, colonizer-persistent (c-p) community structure and maturity index (MI). This work presents results from soils in horticultural and banana plantations in the provinces of Azuay (highlands), El Oro and Guayas (coast), respectively. The results showed average organic matter (OM%), temperature (T°C) and humidity (H%) variables with significant differences (P<0.05) between sampling regions. No organisms of the mycophagous trophic group were found throughout the study. Genera such as Tylenchus, Helycotylenchus and Pratylenchus, represented more than 50% of the total of those collected. However, a notable difference was observed in the predatory trophic group, with a higher abundance in the coastal region than in the highlands. In general, the Costa and Sierra growing regions had a considerable impact on abundance and physicochemical variables. Climate had an important effect on the distribution and diversity of nematodes, including those of the predatory trophic group. The abundance of the herbivore trophic group could be mediated by the presence of the predator trophic group. [ABSTRACT FROM AUTHOR]

The present study aimed to detect the parasitic fauna associated with black rats (Rattus rattus) from southeastern Algeria. It showed the presence of seven species of parasitic fungi namely Penicillium sp. (Prevalence Pr=91.3%), Aspergillus niger (Pr=91.3%), Alternaria sp. (Pr=58.7%), Cladosporium sp. (Pr=87%), Microsporum sp. (Pr=19.6%), Trichophyton sp. (Pr=21.7%) and Chrysosporium sp. (Pr=10.9%), noting that saprophytic fungi were the most recorded. On the other hand, according to the richness (S), adults (S = 7) and sub-adults (S = 7) of black rats were the most infested, with leaning for males compared to females, considering all the isolated species as satellites except the Chrysosporium sp. (2.9%) which is presented as a rare species. Concerning parasitic bacteria, aged rats were the most infected followed by adults and sub-adults where total coliforms were present in all individuals of the three classes tested. However, fecal streptococci were noted with a similar infestation rate in all age groups. Unlike this, clostridium sulfite-reducer (CSR) was mostly recorded on aged rats. Concerning the endoparasites found in the intestines of black rats, the pinworms (Syphacia muris, Syphacia obvelata, and Aspiculuris tetraptera) were more abundant than the other species. Hence, the current study allowed us to demonstrate that black rats can be considered an important reservoir of several microorganisms that can hold germs and represent a threat to biomedical and veterinary public health. [ABSTRACT FROM AUTHOR]

Genetic studies of nematodes have been dominated by Caenorhabditis elegans as a model species. A lack of genomic resources has limited the expansion of genetic research to other groups of nematodes. Here, we report a draft genome assembly of a mermithid nematode, Mermis nigrescens. Mermithidae are insect parasitic nematodes with hosts including a wide range of terrestrial arthropods. We sequenced, assembled, and annotated the whole genome of M. nigrescens using nanopore long reads and 10X Chromium link reads. The assembly is 524 Mb in size consisting of 867 scaffolds. The N50 value is 2.42 Mb, and half of the assembly is in the 30 longest scaffolds. The assembly BUSCO score from the eukaryotic database (eukaryota_odb10) indicates that the genome is 86.7% complete and 5.1% partial. The genome has a high level of heterozygosity (6.6%) with a repeat content of 83.98%. mRNA-seq reads from different sized nematodes (≤2 cm, 3.5–7 cm, and >7 cm body length) representing different developmental stages were also generated and used for the genome annotation. Using ab initio and evidence-based gene model predictions, 12,313 protein-coding genes and 24,186 mRNAs were annotated. These genomic resources will help researchers investigate the various aspects of the biology and host–parasite interactions of mermithid nematodes. [ABSTRACT FROM AUTHOR]

Nuclear hormone receptors (NHRs) are a deeply-conserved superfamily of metazoan transcription factors, which fine-tune the expression of their regulatory target genes in response to a plethora of sensory inputs. In nematodes, NHRs underwent an explosive expansion and many species have hundreds of nhr genes, most of which remain functionally uncharacterized. However, recent studies have reported that two sister receptors, Ppa-NHR-1 and Ppa-NHR-40, are crucial regulators of feeding-structure morphogenesis in the diplogastrid model nematode Pristionchus pacificus. In the present study, we functionally characterize Ppa-NHR-10, the sister paralog of Ppa-NHR-1 and Ppa-NHR-40, aiming to reveal whether it too regulates aspects of feeding-structure development. We used CRISPR/CAS9-mediated mutagenesis to create small frameshift mutations of this nuclear receptor gene and applied a combination of geometric morphometrics and unsupervised clustering to characterize potential mutant phenotypes. However, we found that Ppa-nhr-10 mutants do not show aberrant feeding-structure morphologies. Instead, multiple RNA-seq experiments revealed that many of the target genes of this receptor are involved in lipid catabolic processes. We hypothesized that their mis-regulation could affect the survival of mutant worms during starvation, where lipid catabolism is often essential. Indeed, using novel survival assays, we found that mutant worms show drastically decreased starvation resistance, both as young adults and as dauer larvae. We also characterized genome-wide changes to the transcriptional landscape in P. pacificus when exposed to 24 h of acute starvation, and found that Ppa-NHR-10 partially regulates some of these responses. Taken together, these results demonstrate that Ppa-NHR-10 is broadly required for starvation resistance and regulates different biological processes than its closest paralogs Ppa-NHR-1 and Ppa-NHR-40. [ABSTRACT FROM AUTHOR]

In soil-based protected cultivation, the prevalence of certain diseases like bacterial wilt and nematodes in the bell pepper plant due to its successive cropping pose a threat for maximizing productivity. Considering the potential of grafting to alleviate various biotic and abiotic stresses, often relying on rootstock's capability, we explored the potential of diverse local genotypes of Capsicum spp. to utilize as rootstocks. In this research, we assessed the performance of a commercial bell pepper cv. Massilia F1, grafted onto twenty-five rootstocks along with non-grafted and self-grafted Massilia plants under artificial inoculation conditions of bacterial wilt (Ralstonia solanacearum) and nematodes (Meloidogyne incognita) in a plastic greenhouse. The response of rootstock grafting was determined by assessing disease incidences and their effect on plants growth, yield, and physiology, as well as their efficiency in nutrient accumulation. The grafted plants exhibited varied responses to diseases depending on rootstock genotypes. Notably, Massilia grafted onto the CRS-8 and CRS-1 rootstocks exhibited high bacterial wilt resistance by showing lower percent disease incidence (PDI) (22.22 and 27.78 percent, respectively). Others, like CRS-11, CRS-12, CRS-13, CRS-21, and CRS-24, showed moderate resistance (PDI ranging from 33.33 to 38.89 percent, respectively). The self-grafted and non-grafted plants were highly susceptible and recorded complete mortality by the end of the experiment. All of the grafted plants exhibited promising resistance against nematode infestation compared to non-grafted and self-grafted plants with 26.17 and 8.67 percent root galls, respectively. The susceptible plants had lower shoot and root dry weights, while the resistant graft combinations had comparatively higher biomass. Importantly, grafting induced earliness in flowering and provided higher yields, especially in graft combinations involving the CRS-15, CRS-11, and CRS-8 rootstocks. These graft combinations exhibited significantly higher yields over the non-grafted and self-grafted plants. The plant yield was positively associated with plant height, number of leaves, fresh and dry weight of roots, number of fruits per plant, and average fruit weight, but negatively related to bacterial wilt and root-knot nematode incidences. The increased level of antioxidant enzymes such as polyphenol oxidase (PPO), phenylalanine ammonia lyase (PAL), and peroxidase (POD) and the higher total chlorophyll content in the resistant grafted plants indicates their better ability to cope with diseases at the cellular level. This study highlights the robust performance of certain rootstocks from Capsicum annuum (CRS-1, CRS-2, CRS-11, CRS-15) and Capsicum frutescens (CRS-8, CRS-13, CRS-22) species across multiple measured parameters. Grafting emerges as a sustainable solution for bell pepper production in bacterial wilt- and nematode-infested soil under plastic greenhouses. [ABSTRACT FROM AUTHOR]

The longjaw tapertail anchovy Coilia nasus, which migrates from ocean to freshwater for spawning in spring, is an important anadromous fish with ecological and cultural significance. To determine parasite infection in anadromous C. nasus, a total of 103 fish from the Yangtze River were collected and examined in 2021 and 2022. The overall infection prevalence of nematodes in C. nasus was 100%, with a mean intensity of 13.81 ± 16.45. The mean intensity of nematode infections in 2022 was significantly higher than that observed in 2021 across all sampling sites (p < 0.05). Nematodes were widely detected in the mesentery, pyloric cecum, stomach, and liver, among which the mesentery accounted for the highest proportion, reaching up to 53.52%. A total of eight ascaridoid nematodes belonging to the family Anisakidae and Raphidascarididae were identified by using morphological characters and molecular biological techniques, including two species of Anisakis, five species of Hysterothylacium, and one species of Raphidascaris. A. pegreffii was found as the predominant species, accounting for 48.65% of all identified parasitic nematodes in liver, while Raphidascaris sp. was the most common nematode in the mesentery, pyloric cecum, and stomach, reaching up to 39.81%, 36.21%, and 74.36%, respectively. The present study systematically investigated the parasitic status and community structure of the nematode in C. nasus during its migration in the Yangtze River. This research provides a foundation for studying the impact of nematode parasitism on the reproductive migration and population recruitment of C. nasus, and offers valuable insights for biomarker screening and nematode identification in C. nasus. [ABSTRACT FROM AUTHOR]

The utilization of Trichoderma longibrachiatum filtrate as a safe biocontrol method for producing zinc nanoparticles is a promising approach for managing pests and diseases in agricultural crops. The identification of Trichoderma sp. was achieved through PCR amplification and sequencing of 18s as ON203115, while the synthesis of ZnO-NPs was accomplished by employing Trichoderma filtration. The presence of ZnO-NPs was confirmed by observing a color change to dark green, along with the use of visible and UV spectrophotometers, and the formation and chemical structure of ZnO-NPs were examined. Direct exposure to ZnO-NPs exhibited a significant inhibitory effect on the growth of Fusarium oxysporum at 80.73% compared with control. Also, the percent mortality of Meloidogyne incognita second juveniles stage (J2s) results showed 11.82%, 37.63%, 40.86%, and 89.65% after 6, 12, 24, and 72 h, respectively in vitro. Disease resistance was assessed in the greenhouse against M. incognita and F. oxysporum using the drench application of ZnO-NPs. The application of ZnO-NPs significantly reduced the disease severity of F. oxysporum and improved the quality and quantity of sweet pepper yield. In addition, the application of ZnO-NPs to M. incognita resulted in a significant reduction in the number of nematode galls, egg masses per root, eggs/egg mass, and females by 98%, 99%, 99.9%, and 95.5% respectively. Furthermore, it was observed that the application of ZnO-NPs to pepper plants not only inhibited the growth of F. oxysporum and M. incognita, but also promoted the recovery of pepper plants as indicated by improvements in stem length by 106%, root length 102%, fresh weight 112%, root fresh weight 107%, and leaf area 118% compared to healthy control plants. Additionally, real-time PCR application and DD-PCR technique revealed that the application of ZnO-NPs stimulated the secretion of certain enzymes. These findings suggest that the biosynthesized ZnO-NPs possess anti-nematode and antifungal properties, making them effective for protecting plants against M. incognita and F. oxysporum invasion in soil. This study significantly contributes to our understanding of the nematicidal and fungicidal activities of ZnO-NPs in suppressing soil-borne diseases. [ABSTRACT FROM AUTHOR]

Beech leaf disease (BLD) is a foliar disease of American Beech (Fagus grandifolia L.) causally linked to the nematode Litylenchus crenatae mccannii and has rapidly spread throughout central and northeastern North America. This study aimed to characterize the anatomical and physiological differences between asymptomatic and symptomatic leaves to provide evidence for a mechanistic link between abnormal leaf development associated with BLD and the long‐term decline of affected trees. We found that leaf mass per area (LMA) and leaf thickness were 45% and 249% higher in symptomatic regions, respectively. The difference in leaf thickness was largely attributable to the spongy mesophyll being 410% thicker in symptomatic as compared with asymptomatic regions of the leaves, but palisade mesophyll and abaxial epidermal tissues were also thicker in symptomatic regions. While major vein density was not significantly different, minor vein density was significantly lower in symptomatic regions, suggesting that the effects on leaf development occur after the formation and initial development of first‐ and second‐order veins. Stomatal density was also lower in symptomatic leaves. Maximum photosynthetic rates were approximately 61% lower in symptomatic leaves and respiration rate increased as the percentage of affected leaf tissue increased. Collectively, our data show reduced photosynthetic capacity, increased respiration rates, and higher leaf construction costs, which will likely have a negative, long‐term impact on the carbon balance of trees affected by BLD. [ABSTRACT FROM AUTHOR]

Highly diverse exoenzymes mediate the energy flow from substrates to the multitrophic microbiota within the soil decomposer micro‐food web. Here, we used a "soil enzyme profile analysis" approach to establish a series of enzyme profile indices; those indices were hypothesized to reflect micro‐food web features. We systematically evaluated the shifts in enzyme profile indices in relation to the micro‐food web features in the restoration of an abandoned cropland to a natural area. We found that enzymatic C:N stoichiometry and decomposability index were significantly associated with substrate availability. Furthermore, the higher Shannon diversity index in the exoenzyme profile, especially for the C‐degrading hydrolase, corresponded to a greater microbiota community diversity. The increased complexity and stability of the exoenzyme network reflected similar changes with the micro‐food web networks. In addition, the gross activity of the enzyme profile as a parameter for soil multifunctionality, effectively predicted the substrate content, microbiota community size, diversity, and network complexity. Ultimately, the proposed enzymic channel index was closely associated with the traditional decomposition channel indices derived from microorganisms and nematodes. Our results showed that soil enzyme profile analysis reflected very well the decomposer food web features. Our study has important implications for projecting future climate change or anthropogenic disturbance impacts on soil decomposer micro‐food web features by using soil enzyme profile analysis. Highlights: Soil enzyme profile analysis for indicating decomposer micro‐food web features was first proposed.Diversity indication utilities for contrasting enzyme profiles were different.Protozoa channel index and enzymatic channel index were proposed. [ABSTRACT FROM AUTHOR]

ES‐62, a protein secreted by Acanthocheilonema viteae, is anti‐inflammatory by virtue of covalently attached phosphorylcholine (PC) residues and thus a library of drug‐like small molecule analogues (SMAs) based on its PC moieties has been designed for therapeutic purposes. Two members, SMAs 11a and 12b, were previously found to suppress production of pro‐inflammatory cytokines by mouse bone marrow‐derived macrophages (BMMs) exposed to cytosine‐phosphate‐guanosine oligodeoxynucleotides (CpG), agonists for Toll‐like receptor 9. In order to explore the mechanism of action underlying such activities, an untargeted mass spectrometry‐based metabolomics screen was undertaken. Stimulation of BMMs with CpG produced significant metabolic changes relating to glycolysis and the TCA cycle but the SMAs had little impact on this. Also, the SMAs did not promote alterations in metabolites known to be associated with macrophage M1/M2 polarization. Rather, BMMs exposed to SMAs 11a or 12b prior to CpG treatment, or even alone, revealed downregulation of metabolites of creatine, a molecule whose major role is in the transport of high energy phosphate from the mitochondria to the cytosol. These data therefore provide insight into a possible mechanism of action of molecules with significant therapeutic potential that has not previously been described for parasitic worm products. [ABSTRACT FROM AUTHOR]

Microdeletion syndromes are genetic diseases caused by multilocus chromosomal deletions too small to be detected by karyotyping. They are typified by complex pleiotropic developmental phenotypes that depend both on the extent of the deletion and variations in genetic background. Microdeletion alleles cause a wide array of consequences involving multiple pathways. How simultaneous haploinsufficiency of numerous adjacent genes leads to complex and variable pleiotropic phenotypes is not well understood. CRISPR/Cas9 genome editing has been shown to induce microdeletion-like alleles at a meaningful rate. Here, we describe a microdeletion allele in Caenorhabditis elegans recovered during a CRISPR/Cas9 genome editing experiment. We mapped the allele to chromosome V, balanced it with a reciprocal translocation crossover suppressor, and precisely defined the breakpoint junction. The allele simultaneously removes 32 protein-coding genes, yet animals homozygous for this mutation are viable as adults. Homozygous animals display a complex phenotype including maternal effect lethality, producing polynucleated embryos that grow into uterine tumors, vulva morphogenesis defects, body wall distensions, uncoordinated movement, and a shortened life span typified by death by bursting. Our work provides an opportunity to explore the complexity and penetrance of microdeletion phenotypes in a simple genetic model system. [ABSTRACT FROM AUTHOR]

This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'. [ABSTRACT FROM AUTHOR]

Strongyloides ratti is a natural parasite of wild rats and most laboratory mouse strains are also fully permissive. The infection can be divided into three distinct phases: the tissue migration of the infective third stage larvae during the first two days, the early intestinal establishment of S. ratti parasites molting to adults on days three to six and the later intestinal parasitic phase until the end of infection. Immunocompetent mice terminate the S. ratti infection after one month and are semi-resistant to a second infection. Employing the powerful tools of mouse immunology has facilitated a detailed analysis of the initiation, execution and regulation of the immune response to S. ratti. Here we review the information collected to date on the protective immune response to migrating S. ratti larvae in tissues and to adult parasites in the intestine. We show that depending on the phase of infection, a site-specific portfolio of immune effector mechanisms is required for infection control. In addition, we summarize the strategies employed by S. ratti to evade the immune system and survive long enough in its host to replicate despite an effective immune response. Selected murine studies using the closely related Strongyloides venezuelensis will be discussed. This article is part of the Theo Murphy meeting issue 'Strongyloides: omics to worm-free populations'. [ABSTRACT FROM AUTHOR]

[Display omitted] • Commercial translation of an ELISA for mucosal/luminal cyathostomins is described. • The test demonstrates high (>0.9) ROC-AUC values for various cyathostomin burden thresholds. • The test has high sensitivity (>90%)/specificity (>70%) at selected cyathostomin burden ELISA cut-off values. • The percentage of test-positives associates with egg shedding levels in populations. • Logistic regression modelling shows promise as a method for predicting burden. Cyathostomins are ubiquitous equine nematodes. Infection can result in larval cyathostominosis due to mass larval emergence. Although faecal egg count (FEC) tests provide estimates of egg shedding, these correlate poorly with burden and provide no information on mucosal/luminal larvae. Previous studies describe a serum IgG(T)-based ELISA (CT3) that exhibits utility for detection of mucosal/luminal cyathostomins. Here, this ELISA is optimised/validated for commercial application using sera from horses for which burden data were available. Optimisation included addition of total IgG-based calibrators to provide standard curves for quantification of antigen-specific IgG(T) used to generate a CT3-specific 'serum score' for each horse. Validation dataset results were then used to assess the optimised test's performance and select serum score cut-off values for diagnosis of burdens above 1000, 5000 and 10,000 cyathostomins. The test demonstrated excellent performance (Receiver Operating Characteristic Area Under the Curve values >0.9) in diagnosing infection, with >90% sensitivity and >70% specificity at the selected serum score cut-off values. CT3-specific serum IgG(T) profiles in equines in different settings were assessed to provide information for commercial test use. These studies demonstrated maternal transfer of CT3-specific IgG(T) in colostrum to newborns, levels of which declined before increasing as foals consumed contaminated pasture. Studies in geographically distinct populations demonstrated that the proportion of horses that reported as test positive at a 14.37 CT3 serum score (1000-cyathostomin threshold) was associated with parasite transmission risk. Based on the results, inclusion criteria for commercial use were developed. Logistic regression models were developed to predict probabilities that burdens of individuals are above defined thresholds based on the reported serum score. The models performed at a similar level to the serum score cut-off approach. In conclusion, the CT3 test provides an option for veterinarians to obtain evidence of low cyathostomin burdens that do not require anthelmintic treatment and to support diagnosis of infection. [ABSTRACT FROM AUTHOR]

Growth and agricultural production of crops including, Abelmoschus esculentus (okra), a staple and nutritious vegetable cultivated and consumed in sub-Saharan Africa, is threatened and constrained by abiotic and biotic stresses caused by global climate change. While individual stressors cause devastating impacts to agricultural production, the possible combination of different multiple stresses (either jointly or sequentially), could pose a greater threat to global food production and food security. This study aimed at exploring morphological responses of okra plants cv. 'Meya' subjected to individual, sequential and concurrent stresses of drought and Meloidogyne incognita a causative agent of root-knot disease. Results showed both stresses significantly reduced growth and yield components of plants. Individual drought stressed plants significantly reduced growth compared to plants stressed with only nematode infection. Varied morphological differences were observed between plants stressed in sequence and those that received both stresses concomitantly. Plants subjected to dehydration stress prior to nematode infection coped better with the stress combination in comparison to plants that were challenged with nematode infection before dehydration stress and concurrent drought-nematode stress. This okra cultivar was either highly or moderately resistant to nematode infection by moderate formation and establishment of galls and egg masses. Survival mechanisms of this cultivar under both stresses could be primarily linked to its water-use efficiency as well as several cascades of changes in signal transduction pathways. [ABSTRACT FROM AUTHOR]

Background and Objectives Cucumber (Cucumis sativus L.) holds significant agricultural importance in Iran, occupying extensive cultivation areas. Greenhouse conditions favor the proliferation of numerous pests and diseases affecting cucumber growth. Root-knot nematodes inflict yearly damage on cucumber farmers and producers, particularly in tropical and subtropical regions. Cucumbers are susceptible to various plant-parasitic nematodes, with Meloidogyne species, notably rootknot nematodes, posing significant threats. Controlling the nematode is challenging due to its wide host range, short life cycle, high reproductive rate, and parasitism. While chemical control remains prevalent for nematode population management, growing public concern over the environmental and human health impacts of nematicides is driving efforts to restrict their usage. Employing resistant varieties either independently or in conjunction with other strategies is increasingly recognized as a highly effective means of nematode control. Resistant plants prevent the need for long-term rotations and are highly suitable for sustainable agriculture. Consequently, the development of new cucumber varieties and hybrids and the assessment of their resistance can be applied in integrated nematode management. Hence, this research aims to evaluate the resistance of cucumber hybrids to root-knot nematodes (M. incognita) under greenhouse conditions. Materials and Methods Soil and root sampling was undertaken from cucumber cultivation sites in Guilan province. Egg masses were then introduced to the root systems of tomato seedlings, specifically the Early Urbana variety, at the two to four true leaf stage. Subsequently, these seedlings were nurtured for 45 to 60 days under greenhouse conditions. Identification involved the analysis of perineal patterns alongside morphological and morphometric traits of second-stage juveniles. Staining of female nematodes in root tissue was accomplished using the Hartman and Sasser method. Multiple consecutive inoculation cycles were executed on susceptible tomato plants to cultivate a substantial and uncontaminated nematode population. Seed germination took place in Petri dishes, with transfer to individual pots containing a mix of perlite and coco peat in equal measures after 48 hours. These pots were then randomly distributed within the greenhouse, with subsequent maintenance performed as required. The experiment followed a completely randomized design with three replications. Ten weeks post-inoculation, nematode-related parameters, such as the count of galls and egg masses using the Taylor and Sasser method, alongside the number of second-stage juveniles in the soil using the Barker method, were assessed. Subsequently, statistical analysis was carried out utilizing SAS 9.0 software following data normalization. Mean comparisons were conducted using the Tukey test. Results The results showed significant differences in some traits of the hybrids treated with nematodes. Variance analysis revealed no significant differences in specific indicators, including gall count, egg sacs, eggs, second-stage juveniles in the soil, reproduction factor, as well as fresh and dry shoot and root weights across the assessed hybrids. However, significant differences were observed among the growth indices of plants, particularly in fresh and dry shoot weight, fresh root weight, and root volume. The mean weight of the aerial parts in the control was 103.66 g. Hybrid 5×3 exhibited the highest reduction, with a weight of 63.33 g, reflecting a 38.9% decrease compared to the control. Conversely, hybrid 7×6 showed the least disparity, with a weight of 100 g and only a 3.53% reduction. Notably, significant differences were evident in gall index, egg mass index, resistance index, root dry weight, and root length. According to the Taylor and Sasser ranking for determining gall and egg masses indices, hybrid 2×6 exhibited sensitivity, while the remaining hybrids were classified as very sensitive. Regarding the egg masses index, hybrids 5×3, 2×6, and 3×4 displayed relative resistance, whereas the other hybrids were categorized as sensitive. Evaluation based on the reproduction factor and gall index indicated that all hybrids were classified as sensitive. Discussion The study concluded that none of the hybrids exhibited significant resistance indices. However, hybrid 2×6 demonstrated statistical significance in gall index, egg masses, and resistance, while hybrid 2×7 displayed superiority over the control variety in terms of larval count, egg count, and dry shoot weight. Consequently, pending further complementary experiments, these hybrids may be regarded as promising replacement candidates. [ABSTRACT FROM AUTHOR]

This study explores an eco-friendly approach to synthesizing silver nanoparticles (AgNPs) using soybean leaf extracts, employing a reaction with silver nitrate at 65 °C for 2.5 h. Optimal results were achieved at extract concentrations of 3.12 and 6.25 mg of the leaf mL−1, termed 3.12AgNP and 6.25AgNP, respectively. UV-Vis spectrophotometric analysis between 350 and 550 nm exhibited a peak at 410–430 nm, along with a color transition in the suspensions from pale yellow to brown, indicating successful synthesis. Dynamic light scattering (DLS) further delineated the favorable properties of these AgNPs, including nanometric dimensions (73–104 nm), negative charge, and moderate polydispersity, portraying stable and reproducible synthesis reactions. The bioreduction mechanism, possibly expedited by leaf extract constituents such as amino acids, phenolic acids, and polysaccharides, remains to be fully elucidated. Notably, this study underscored the potent nematicidal effectiveness of biosynthesized AgNPs, especially 6.25AgNP, against Pratylenchus brachyurus, which is a common plant-parasitic nematode in tropical soybean cultivation regions. In vitro tests illustrated significant nematicidal activity at concentrations above 25 µmol L−1, while in vivo experiments displayed a pronounced nematode population diminishment in plant roots, particularly with a 6.25AgNP rhizosphere application at concentrations of 500 µmol L−1 or twice at 250 µmol L−1, attaining a reproduction factor below 1 without any morphological nematode alterations. This research highlights the potential of 6.25AgNPs derived from soybean leaf extracts in forging sustainable nematicidal solutions, marking a significant stride toward eco-friendly phytonematode management in soybean cultivation. This novel methodology signals a promising avenue in harnessing botanical resources for nematode control and propelling a greener agricultural horizon. [ABSTRACT FROM AUTHOR]

Metathelazia capsulata (family Pneumospiruridae) is a lungworm parasitizing the bronchi and bronchioles, described in four species of wild carnivores. Very little molecular data are available on this nematode and none on other species of the Pneumospiruridae family. In this work, we describe for the first time the complete mitogenome (mitochondrial genome) of M. capsulata, being the first described of the family Pneumospiruridae. The mitogenome of M. capsulata has 13,659 bp in length, an A + T content of 79.2%. The mitogenome included 12 protein-coding genes (PCGs) (lacking the atp8 gene), 22 tRNA genes, 2 rRNA genes (all the genes are coded by the heavy strand), and an AT-rich region. The PCGs varied in size (232 bp-1645 bp). Only the tRNA-Trp has the standard cloverleaf secondary structure, while the other 21 do not. The AT-rich region, with a 90.5% A + T content and a length of 389 bp, is located between the cox3 and tRNA-Ala genes. Comparison with the mitogenomes of 29 species of Spiruromorpha infraorder, belonging to different families, demonstrates that M. capsulata mitogenome shared the common characteristics of most of them. The phylogeny constructions yielded phylogenies that were in agreement with the obtained previously by using sequences and gene order data of mitogenomes. [ABSTRACT FROM AUTHOR]

Species of the Heterakidae family are similar in appearance. These signs cause difficulties in determining the systematic position of the species. For this purpose, the digestive organs of adult H. gallinarum nematode were studied at the ultrastructural levels by light and electron microscopic methods. The obtained results were compared with the structures of other species of the family. The digestive organs of adult H. gallinarum nematode are divided into 3 parts - stomodeum, intestine and proctodeum. The esophagus in turn is divided into procorpus, metacorpus and bulb. Its wall consists of basement membrane, muscle cells and cuticle. In the bulb, the muscle cells are large and relatively large in number. The intestine is divided into ventricular, middle and prerectal areas. It consists of a thick basement membrane, a single-layered epithelium with microvillas. Epithelial cells are divided into 5 areas that differ from each other according to their structure. The smooth membranes of the epithelial cells create a barrier connection with each other. Sphincter cells are noted at the end of the intestine. After that part, the rectum was found in females and the cloaca in males nematodes. The lumen of both is covered with cuticle. The ultrastructural features of the digestive organs of the nematode H. gallinarum are consistent with the main systematic features of the family. [ABSTRACT FROM AUTHOR]