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Summary: The genus Oscheius includes species with different habits and some of them have been shown to kill some insect pests. The occurrence of Oscheius in hay meadow soils from the area recently invaded by the Japanese beetle Popillia japonica in Lombardy, Italy, has been surveyed. Oscheius myriophilus was detected at five out of 18 sites resulting positive to entomopathogenic nematodes (EPN), either alone or together with other genera of EPN, indicating a widespread occurrence. The morphological analysis of the strains retrieved showed that they are morphologically in agreement with those of the type population and with other populations recently described. The phylogenetic analysis supported the sub-grouping of all sequences of O. myriophilus from Lombardy with those present in the databases and a close relationship with O. safricana was observed. The capacity to kill the laboratory host Galleria mellonella was similar to that observed in a previous study related to isolates from P. japonica , although O. myriophilus did not cause significant mortality in laboratory trials with the invasive beetles. The isolates of O. myriophilus from Lombardy were characterised in relation to their infectivity to G. mellonella and response to environmental stress, such as heat tolerance and desiccation. Overall, O. myriophilus appears to be an important component of the EPN community of hay meadow soil in Lombardy and might play a role in the containment of the invasive P. japonica. [ABSTRACT FROM AUTHOR]

Summary: Cryptaphelenchus species are wood- or bark-inhabiting nematodes, generally mycetophagous and reported to have endophoretic associations with insects. In the present study, we describe two new and one known Cryptaphelenchus species detected in imported and domestic wood samples. Cryptaphelenchus americanum n. sp. and C. minutus were detected in the log samples of Pinus taeda imported from the USA, whereas C. orientalis n. sp. was isolated from the bark of dying Pinus sylvestris trees in Inner Mongolia, China. Both new species displayed characteristic features, including a relatively short body length, four lateral lines, a short post-vulval uterine sac in females, and a distinct cloacal apophysis in male tails. Newly recovered and known species were characterised molecularly, and phylogenetic trees were constructed to study their relationship with related Cryptaphelenchus species. Notably, the genetic divergence observed among Cryptaphelenchus species was found to be more significant compared to morphometrical differences, highlighting the importance of molecular data in taxonomy. The identification of new and known species expands our understanding of the genus and suggests that Cryptaphelenchus species may be under studied, underscoring the necessity for continued exploration. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN), Heterodera glycines, HG type 1.2.5.7 is the most virulent and widespread SCN biotype in the southern states of the USA, but its effect on soybean (Glycine max [L.] Merr.) nitrogen fixation (NF) activity and growth is not well documented. The objectives of this study were to: (1) measure the impact of HG type 1.2.5.7 on NF activity during the early vegetative stage of three soybean genotypes and (2) compare the impact on soybean leaf and root development, and plant growth. The NF activity of two susceptible (S) genotypes ("Ellis" and "Williams 82") and one resistant (R) genotype (PI 88,788), subjected to a 10,000-egg treatment, was measured using an in-situ flow-through acetylene reduction assay. The average NF activity of the soybean genotypes was decreased by SCN activity. Time points assessment showed that the NF activity was differently impacted among the genotypes. Based on the measured values, the NF activity was decreased by 30% in SCN infected plants of Williams 82 but that of PI 88,788 and Ellis was affected. Likewise, soybean leaf color and leaf area were affected by SCN infection, but there was no impact on root length and root area. These results showed that SCN HG type 1.2.5.7 can exhibit varying negative impact on NF and shoot growth of S soybean genotypes, while R genotypes may be unaffected. Thus, indicating genetic resistance continues to be a critical tool for the management of the SCN. [ABSTRACT FROM AUTHOR]

Ticks are ectoparasites responsible for the transmission of various pathogens to vertebrates. They represent one of the major threats to livestock production worldwide due to their impact on the health, production and welfare of livestock destined for human consumption. The development of resistance to the main families of ixodicides used for their control has led to the search for new alternatives, where microbial control is an option. The use of microbial control agents against the tick Rhipicephalus microplus is reviewed in this paper. Bacteria such as Bacillus thuringiensis, Serratia marcescens and Staphylococcus spp. the nematodes Steinernema spp. and Heterorhabditis spp. as well as the fungi Metarhizium anisopliae and Beauveria bassiana are the most studied organisms for use as biological control agents against ticks. Laboratory, stable and field trials with free-living and parasitised ticks have shown that microbial agents can control both susceptible and ixodicide-resistant tick populations. However, multidisciplinary studies using novel tools like genomics, transcriptomics and proteomics should be carried out to understand the virulence factors which microbial agents use to induce pathogenesis and virulence in ticks. In addition, applied research will be carried out with the aim of improving techniques for large-scale application, as well as the improvement of cultivation, storage, formulation and application methods. [ABSTRACT FROM AUTHOR]

We describe a recent case of lymphatic filariasis in Colombia caused by Wuchereria bancrofti nematodes. Our study combines clinical-epidemiologic findings with phylogenetic data. Resurgence of lymphatic filariasis may be linked to increasing urbanization trends and migration from previously endemic regions. Fieldwork can be a beneficial tool for screening and containing transmission. [ABSTRACT FROM AUTHOR]

The objective of this study was to identify genomic regions and genes associated with resistance to gastrointestinal nematodes in Australian Merino sheep in Uruguay, using the single-step GWAS methodology (ssGWAS), which is based on genomic estimated breeding values (GEBVs) obtained from a combination of pedigree, genomic, and phenotypic data. This methodology converts GEBVs into SNP effects. The analysis included 26,638 animals with fecal egg count (FEC) records obtained in two independent parasitic cycles (FEC1 and FEC2) and 1700 50K SNP genotypes. The comparison of genomic regions was based on genetic variances (gVar(%)) explained by non-overlapping regions of 20 SNPs. For FEC1 and FEC2, 18 and 22 genomic windows exceeded the significance threshold (gVar(%) ≥ 0.22%), respectively. The genomic regions with strong associations with FEC1 were located on chromosomes OAR 2, 6, 11, 21, and 25, and for FEC2 on OAR 5, 6, and 11. The proportion of genetic variance attributed to the top windows was 0.83% and 1.9% for FEC1 and FEC2, respectively. The 33 candidate genes shared between the two traits were subjected to enrichment analysis, revealing a marked enrichment in biological processes related to immune system functions. These results contribute to the understanding of the genetics underlying gastrointestinal parasite resistance and its implications for other productive and welfare traits in animal breeding programs. [ABSTRACT FROM AUTHOR]

The ITS‐2‐rRNA has been particularly useful for nematode metabarcoding but does not resolve all phylogenetic relationships, and reference sequences are not available for many nematode species. This is a particular issue when metabarcoding complex communities such as wildlife parasites or terrestrial and aquatic free‐living nematode communities. We have used markerDB to produce four databases of distinct regions of the rRNA cistron: the 18S rRNA gene, the 28S rRNA gene, the ITS‐1 intergenic spacer and the region spanning ITS‐1_5.8S_ITS‐2. These databases comprise 2645, 254, 13,461 and 10,107 unique full‐length sequences representing 1391, 204, 1837 and 1322 nematode species, respectively. The comparative analysis illustrates the complementary value but also reveals a better representation of Clade III, IV and V than Clade I and Clade II nematodes in each case. Although the ITS‐1 database includes the largest number of unique full‐length sequences, the 18S rRNA database provides the widest taxonomic coverage. We also developed PrimerTC, a tool to assess primer sequence conservation across any reference sequence database, and have applied it to evaluate a large number of previously published rRNA cistron primers. We identified sets of primers that currently provide the broadest taxonomic coverage for each rRNA marker across the nematode phylum. These new resources will facilitate more comprehensive metabarcoding of nematode communities using either short‐read or long‐read sequencing platforms. Further, PrimerTC is available as a simple WebApp to guide or assess PCR primer design for any genetic marker and/or taxonomic group beyond the nematode phylum. [ABSTRACT FROM AUTHOR]

Xenorhabdus nematophila is a symbiotic Gammaproteobacterium that produces diverse natural products that facilitate mutualistic and pathogenic interactions in their nematode and insect hosts, respectively. The interplay between X. nematophila secondary metabolism and symbiosis stage is tuned by various global regulators. An example of such a regulator is the LysR-type protein transcription factor LrhA, which regulates amino acid metabolism and is necessary for virulence in insects and normal nematode progeny production. Here, we utilized comparative metabolomics and molecular networking to identify small molecule factors regulated by LrhA and characterized a rare γ-ketoacid (GKA) and two new N-acyl amides, GKA-Arg (1) and GKA-Pro (2) which harbor a γ-keto acyl appendage. A lrhA null mutant produced elevated levels of compound 1 and reduced levels of compound 2 relative to wild type. N-acyl amides 1 and 2 were shown to be selective agonists for the human Gprotein-coupled receptors (GPCRs) C3AR1 and CHRM2, respectively. The CHRM2 agonist 2 deleteriously affected the hatch rate and length of Steinernema nematodes. This work further highlights the utility of exploiting regulators of host-bacteria interactions for the identification of the bioactive small molecule signals that they control. [ABSTRACT FROM AUTHOR]

It is common knowledge that plastic pollution has become one of the foremost environmental problems worldwide. Despite the increasing rates in plastic products recycling, the majority of plastic still finds its way unchecked into the environment. Plastic in itself poses no substantial threat to ecosystems, unlike its degraded components, microplastics (MP) and nanoplastics (NP), which are more reactive and easier to transport due to their reduced size. In recent years, the increasing demand, production, and utilisation of products originally manufactured in the form of MP and NP have further exacerbated the pollution problem. Once released, MPs and NPs tend to accumulate more in terrestrial ecosystems than in aquatic environments, an area that has been researched more comprehensively. Consequently, the degraded components of plastic accumulate within soil-dwelling organisms, which can then further break them down (degrade) through their metabolism. The aim of this study was to provide an overview of the ecotoxicity of MP and NP specifically on earthworms, as representatives of the phylum annelid worm (Annelida), and on nematodes (phylum Nematoda), the two most prevalent groups of soil-dwelling invertebrates. Research into the effects of MP and NP on earthworms has so far been conducted on the species Eisenia fetida, Eisenia andrei, and Lumbricus terrestris, with the species Caenorhabditis elegans serving as a representative nematode species. These organisms were exposed to polyethylene (PE), polystyrene (PS), and polypropylene (PP) particles of varying sizes and concentrations. The results of numerous studies on the harmful effects of these polymeric materials on earthworms and nematodes were measured by testing for inhibition of survival and growth rate, showing significant body weight loss, along with damage to the digestive system, and oxidative stress. [ABSTRACT FROM AUTHOR]

Left unchecked, plant-parasitic nematodes have the potential to devastate crops globally. Highly effective but non-selective nematicides are justifiably being phased-out, leaving farmers with limited options for managing nematode infestation. Here, we report our discovery of a 1,3,4-oxadiazole thioether scaffold called Cyprocide that selectively kills nematodes including diverse species of plant-parasitic nematodes. Cyprocide is bioactivated into a lethal reactive electrophilic metabolite by specific nematode cytochrome P450 enzymes. Cyprocide fails to kill organisms beyond nematodes, suggesting that the targeted lethality of this pro-nematicide derives from P450 substrate selectivity. Our findings demonstrate that Cyprocide is a selective nematicidal scaffold with broad-spectrum activity that holds the potential to help safeguard our global food supply. Plant-parasitic nematodes have the potential to destroy crops globally, and limited options for managing nematode infestation are available. Here, the authors report the 1,3,4-oxadiazole thioether scaffold called Cyprocide that selectively kills nematodes including diverse species of plant-parasitic nematodes. [ABSTRACT FROM AUTHOR]

The article presents a study which examined how the abundance of tylenchid nematodes changes in response to various abiotic soil factors in Vasai, Palghar in Maharashtra, India. Topics discussed include site selection for taxonomic and ecological studies, procedure of sampling of soil, and processing of soil samples and extraction of nematodes.

The use of endophytic microbes is increasing in commercial agriculture. This review will begin with a strain selection. Most strains will not function well, so only a few provide adequate performance. It will also describe the endophyte–plant relationship and the fungi and bacteria involved. Their abilities to alleviate biotic (diseases and pests) and abiotic stresses (drought, salt, and flooding) to remediate pollution and increase photosynthetic capabilities will be described. Their mechanisms of action will be elucidated. These frequently result in increased plant yields. Finally, methods and practices for formulation and commercial use will be described. [ABSTRACT FROM AUTHOR]

Purpose: Without accurate data on soil carbon (C) components and the relationships between soil C, soil respiration and biological C, it is challenging to produce assessments of the C sequestration rate in the process of soil remediation. Accordingly, it is essential to investigate the variations of soil C sources in different remediation treatments. Methods: To find out the contributors of soil C sequestration, we compared the different forms of soil C and soil respiration in cadmium (Cd)-polluted soil with morning glory, microbes or morning glory + microbe (M + microbe) remediation treatments. Results: Results indicated that (1) M + microbe treatments showed a higher Cd removal rate than microbe treatments; (2) soil C contents in morning glory + Lactobacillus + Saccharomyces (M + I) treatment was highest on day 80, however, soil C contents and soil respiration in other treatments declined with increasing remediation time; (3) soils with microbe application had higher microbial biomass carbon (MBC) compared with soils without microbe application; (4) nematode production C and respiration C increased with remediation duration; (5) the connection between soil organic carbon (SOC) and MBC was not observable; and (6) the disparities in soil C components between day 40 and day 80 were more pronounced compared with those between day 80 and day 120. Conclusion: The paper discusses the strengths and weaknesses of each soil Cd remediation methods, ultimately determining that the integration of morning glory, Bacillus velezensis and Saccharomyces may maximize the rate of soil carbon sequestration. [ABSTRACT FROM AUTHOR]

Apple replant disease (ARD) may cause significant losses both in commercial orchards and in fruit tree nurseries. The negative effects of ARD may be limited by using biofumigation. The aim of the study was to assess the influence of this treatment on the biological properties of replanted soil in a tree nursery. In two-year experiment, apple trees of the 'Golden Delicious' cultivar were used. The trees were planted into soil from two sites. The soil from one site had not been used in a nursery before (crop rotation soil). The other soil had been used for the production of apple trees (replanted soil). Three species of plants were used in the replanted soil as a forecrop: French marigold (Tagetes patula), white mustard (Sinapis alba), and oilseed radish (Raphanus sativus var. oleifera). The following parameters were assessed in the experiment: the enzyme and respiratory activity of the soil, the total count of bacteria, fungi, oomycetes and actinobacteria in the soil, as well as the count and species composition of soil nematodes. The vegetative growth parameters of the apple trees were also assessed. The biological properties of the replanted soil were worse than those of the crop rotation soil. In the replanted soil, the organic matter content, enzyme and respiratory activity as well as the count of soil microorganisms were lower. The biofumigants, used as a forecrop on the replanted soil, significantly increased its enzyme activity and respiratory activity. Dehydrogenase activity increased more than twofold. Growth parameters of the trees were significantly improved. The height of the trees increased by more than 50%, and the leaf area, weight and total length of side shoots were higher as well. The density of nematodes in the replanted soil after biofumigation was significantly reduced, with a larger reduction in the marigold fumigated soil. Eight of the eleven nematode species were completely reduced in the first year after biofumigation treatment. [ABSTRACT FROM AUTHOR]

The economic impact of gastrointestinal (GI) nematode infections on livestock production is well documented worldwide. Increasing evidence supports the hypothesis that parasite colonization induces significant changes in the GI tract environment and, therefore, in the landscape where the microbiota and parasites occur. Understanding the interactions between bacterial and parasite populations in the digestive tract of livestock may be useful to design parasite control strategies based on microbiota modification. The aims of this work were to investigate the impact of the oxytetracycline-mediated manipulation of the gut microbial community on the composition of GI nematode populations in naturally infected sheep and to explore changes in the GI microbial communities after nematode population treatment with the anthelmintic compound monepantel. Extensive manipulation of the GI microbiota with a therapeutic dose of the long-acting oxytetracycline formulation did not induce significant changes in the GI nematode burden. The gut microbiota of treated animals returned to control levels 17 days after treatment, suggesting strong resilience of the sheep microbial community to antibiotic-mediated microbiota perturbation. A significant decrease of the bacterial Mycoplasmataceae family (Log2FC = -4, Padj = 0.001) and a marked increase of the Methanobacteriaceae family (Log2FC = 2.9, Padj = 0.018) were observed in the abomasum of sheep receiving the monepantel treatment. While a comprehensive evaluation of the interactions among GI mycoplasma, methanobacteria and nematode populations deserves further assessment, the bacteria-nematode population interactions should be included in future control programs in livestock production. Understanding how bacteria and parasites may influence each other in the GI tract environment may substantially contribute to the knowledge of the role of microbiota composition in nematode parasite establishment and the role of the parasites in the microbiota composition. [ABSTRACT FROM AUTHOR]

Understanding the transcriptional regulatory characteristics throughout the embryogenesis of plant-parasitic nematodes is crucial for elucidating their developmental processes' uniqueness. However, a challenge arises due to the lack of suitable technical methods for synchronizing the age of plant-parasitic nematodes embryo, it is difficult to collect detailed transcriptome data at each stage of embryonic development. Here, we recorded the 11 embryonic developmental time-points of endophytic nematode Meloidogyne incognita (isolated from Wuhan, China), Heterodera glycines (isolated from Wuhan, China), and Ditylenchus destructor (isolated from Jinan, China) species, and constructed transcriptome datasets of single embryos of these three species utilizing low-input smart-seq2 technology. The datasets encompassed 11 complete embryonic development stages, including Zygote, 2-cell, 4-cell, 8-cell, 24–44 cell, 64–78 cell, Comma, 1.5-fold, 2-fold, Moving, and L1, each stage generated four to five replicates, resulting in a total of 162 high-resolution transcriptome libraries. This high-resolution cross-species dataset serves as a crucial resource for comprehending the embryonic developmental properties of plant-parasitic nematodes and for identifying functional regulatory genes during embryogenesis. [ABSTRACT FROM AUTHOR]

The potato cyst nematode Globodera rostochiensis originates from the Andean Mountain region in South America and has unintentionally been introduced to all inhabited continents. Several studies have examined the population genetic structure of this pest in various countries by using microsatellite markers. However, merging microsatellite data produced from different laboratories is challenging and can introduce uncertainty when interpreting the results. To overcome this challenge and to explore invasion routes of this pest, we have genotyped 22 G. rostochiensis populations from all continents. Within populations, the highest genetic diversity was observed in the South American populations, the European populations showed an intermediate level of genetic diversity and the remaining populations were the less diverse. This confirmed pre-existing knowledge such as a first introduction event from South America to Europe, but the less diverse populations could originate either from South America or from Europe. At the continental scale, STRUCTURE genetic clustering output indicated that North America and Asia have experienced at least two introduction events. Comparing different evolutionary scenarios, the Approximate Bayesian Computation analysis showed that Europe served as a secondary distribution centre for the invasion of G. rostochiensis into all other continents (North America, Africa, Asia and Oceania). [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]

Summary: Root‐knot nematodes (RKN; Meloidogyne species) are plant pathogens that introduce several effectors in their hosts to facilitate infection. The actual targets and functioning mechanism of these effectors largely remain unexplored. This study illuminates the role and interplay of the Meloidogyne javanica nematode effector ROS suppressor (Mj‐NEROSs) within the host plant environment.Mj‐NEROSs suppresses INF1‐induced cell death as well as flg22‐induced callose deposition and reactive oxygen species (ROS) production. A transcriptome analysis highlighted the downregulation of ROS‐related genes upon Mj‐NEROSs expression. NEROSs interacts with the plant Rieske's iron–sulfur protein (ISP) as shown by yeast‐two‐hybrid and bimolecular fluorescence complementation.Secreted from the subventral pharyngeal glands into giant cells, Mj‐NEROSs localizes in the plastids where it interacts with ISP, subsequently altering electron transport rates and ROS production. Moreover, our results demonstrate that isp Arabidopsis thaliana mutants exhibit increased susceptibility to M. javanica, indicating ISP importance for plant immunity.The interaction of a nematode effector with a plastid protein highlights the possible role of root plastids in plant defense, prompting many questions on the details of this process. [ABSTRACT FROM AUTHOR]

Unlike sedentary plant-parasitic nematodes, migratory plant endoparasitic nematodes (MPENs) are unable to establish permanent feeding sites, and all developmental stages (except eggs) can invade and feed on plant tissues and can be easily overlooked because of the unspecific symptoms. They cause numerous economic losses in agriculture, forestry, and horticulture. In order to understand the pathogenetic mechanism of MPENs, here we describe research on functions and host targets focused on currently identified effectors from six MPENs, namely Radopholus similis, Pratylenchus spp., Ditylenchus destructor, Bursaphelenchus xylophilus, Aphelenchoides besseyi, and Hirschmanniella oryzae. This information will provide valuable insights into understanding MPEN effectors and for future fostering advancements in plant protection. [ABSTRACT FROM AUTHOR]

Unravelling the multifaceted and bidirectional interactions between microbiota and host physiology represents a major scientific challenge. Here, we utilise the nematode model, Pristionchus pacificus, coupled to a laboratory-simulated decay process of its insect host, to mimic natural microbiota succession and investigate associated tripartite interactions. Metagenomics reveal that during initial decay stages, the population of vitamin B-producing bacteria diminishes, potentially due to a preferential selection by nematodes. As decay progresses to nutrient-depleted stages, bacteria with smaller genomes producing less nutrients become more prevalent. Lipid utilisation and dauer formation, representing key nematode survival strategies, are influenced by microbiota changes. Additionally, horizontally acquired cellulases extend the nematodes' reproductive phase due to more efficient foraging. Lastly, the expressions of Pristionchus species-specific genes are more responsive to natural microbiota compared to conserved genes, suggesting their importance in the organisms' adaptation to its ecological niche. In summary, we show the importance of microbial successions and their reciprocal interaction with nematodes for insect decay in semi-artificial ecosystems. This study uses decomposing beetle grubs to replicate the natural microbial habitat of a nematode model organism. The approach enables exploration of interactions between nematodes and their microbiota and was used to show the importance of microbial successions and their reciprocal interaction with nematodes for insect decay. [ABSTRACT FROM AUTHOR]

In Sudan, resistance to benzimidazoles has been reported recently in cattle and goats from South Darfur. Herein, ivermectin efficacy against gastrointestinal nematodes (GINs) was evaluated in sheep and goats in three study areas in South Darfur. The faecal egg count reduction test (FECRT) was used to evaluate the efficacy of ivermectin in sheep and goats naturally infected with GINs in the region of Bulbul (goats: n = 106), Kass (goats: n = 40) and Nyala (Domaia (sheep: n = 47, goats: n = 77) and the University farm (goats: n = 52)), using different treatment plans, and the efficacy was evaluated 12 days after treatment. Ivermectin efficacy was also evaluated in goats experimentally infected using local Haemonchus contortus isolates from Kass and Nyala. Nematodes surviving ivermectin treatment in goats in Bulbul and Nyala were harvested and larvae used to infect worm-free male sheep (n = 6, ≤6 months old). Infected sheep were dosed subcutaneously with ivermectin every eight days with increasing doses from 0.2 mg/kg to 1.6 mg/kg bodyweight (bw). Reduced ivermectin efficacy was identified in sheep and goats in the four study locations. Using a paired statistic, the efficacy of a therapeutic dose in sheep was 75.6% (90% upper credible limit (UCrL): 77.5%), while twice the recommended dose led to a reduction of 92.6% (90% UCrL: 93.3%). In goats, the FECRs of a therapeutic dose were 72.9–95.3% (90% UCrL range: 73.6–95.7%) in Bulbul, Nyala Domaia, Nyala University farm and Kass. Twice the dose recommended for goats in Bulbul revealed a 90% UCrL of 87.6%. All post-treatment faecal cultures contained only Haemonchus spp. larvae. The experimental infection trials in sheep and goats supported our findings from field trials and calculated upper 90% CrL of below 98.9%. For the first time highly ivermectin resistant H. contortus populations have been identified in sheep and goats in Sudan, and resistance was experimentally confirmed. [ABSTRACT FROM AUTHOR]

Phenotypic plasticity often requires the coordinated response of multiple traits observed individually as morphological, physiological or behavioural. The integration, and hence functionality, of this response may be influenced by whether and how these component traits share a genetic basis. In the case of polyphenism, or discrete plasticity, at least part of the environmental response is categorical, offering a simple readout for determining whether and to what degree individual components of a plastic response can be decoupled. Here, we use the nematode Pristionchus pacificus, which has a resource polyphenism allowing it to be a facultative predator of other nematodes, to understand the genetic integration of polyphenism. The behavioural and morphological consequences of perturbations to the polyphenism's genetic regulatory network show that both predatory activity and ability are strongly influenced by morphology, different axes of morphological variation are associated with different aspects of predatory behaviour, and rearing environment can decouple predatory morphology from behaviour. Further, we found that interactions between some polyphenism-modifying genes synergistically affect predatory behaviour. Our results show that the component traits of an integrated polyphenic response can be decoupled and, in principle, selected upon individually, and they suggest that multiple routes to functionally comparable phenotypes are possible. [ABSTRACT FROM AUTHOR]

The productivity of agricultural ecosystems is heavily influenced by soil-dwelling organisms. To optimize agricultural practices and management, it is critical to know the composition, abundance, and interactions of soil microorganisms. Our study focused on Acrobeles complexus nematodes collected from tomato fields in South Africa and analyzed their associated bacterial communities utilizing metabarcoding analysis. Our findings revealed that A. complexus forms associations with a wide range of bacterial species. Among the most abundant species identified, we found Dechloromonas sp., a bacterial species commonly found in aquatic sediments, Acidovorax temperans, a bacterial species commonly found in activated sludge, and Lactobacillus ruminis, a commensal motile lactic acid bacterium that inhabits the intestinal tracts of humans and animals. Through principal component analysis (PCA), we found that the abundance of A. complexus in the soil is negatively correlated with clay content (r = -0.990) and soil phosphate levels (r = -0.969) and positively correlated with soil sand content (r = 0.763). This study sheds light on the bacterial species associated to free-living nematodes in tomato crops in South Africa and highlights the occurrence of various potentially damaging and beneficial nematode-associated bacteria, which can in turn, impact soil health and tomato production. [ABSTRACT FROM AUTHOR]

(1) Background: Although Physaloptera retusa is one of the most widespread species infecting reptiles in the Americas, numerous taxonomic problems and little genetic data are associated with it. To clarify the taxonomy of this species, we used an integrative approach. (2) Methods: Physaloptera retusa-infecting Erythrolamprus typhlus (snake) from the Pantanal wetlands, Brazil, was morphologically and genetically characterised (18S and 28S rDNA; COI mtDNA) and compared with conspecific sequences available in GenBank, from parasites of Tupinambis teguixin (lizard), using species delimitation methods. Type specimens of P. liophis were re-evaluated given its morphological similarities with P. retusa. (3) Results: The morphology of the present specimens was equal to that of P. retusa, in which the only difference from P. liophis was the relative position of the vulva. Species delimitation methods were more accurate for the COI dataset; all of them (except ABGD) indicated interspecificity among P. retusa sequences. However, a lack of morphological data or voucher material, associated with the deposited sequences, prevented more assertive conclusions. (4) Conclusions: The present results highlight the importance of a clear association between genetic data and morphology of the isolation source, or at least its adequate vouchering. Moreover, P. retusa may represent a species complex in cryptic speciation, since it is widespread and has low hosts specificity. [ABSTRACT FROM AUTHOR]

In the Pistoia Nursery-Ornamental Rural District (Italy), a leader in Europe in ornamental nurseries covering over 5200 hectares with over 2500 different species of plant, plant-parasitic nematodes represent a serious concern. The potential efficacy of a pot cultivation system using commercial substrates to control plant-parasitic nematodes was assessed. On two different plant species, two different pot cultivation managements, potted plants, and potted plants previously cultivated in natural soil were compared to plants only cultivated in natural soil. The entire soil nematode structure with and without plants was evaluated. The relationship between soil properties and soil nematode community was investigated. All the studied substrates were free from plant-parasitic nematodes. Regarding free-living nematodes, Peat–Pumice showed nematode assemblage established by colonizer and extreme colonizer bacterial feeders, whereas Peat–Perlite included both bacterial and fungal feeders, and, finally, coconut fiber also included omnivores and predators. In farming, the substrates rich in organic matter such as coconut fiber could still play an important role in suppressing plant-parasitic nematodes because of the abundance of free-living nematodes. In fact, they are of crucial importance in both the mineralization of organic matter and the antagonistic control of plant-parasitic nematodes. Potting systems equally reduce virus-vector nematodes and improve the prey/predator ratio favoring natural control. [ABSTRACT FROM AUTHOR]

Plant-parasitic nematodes pose a significant threat to economically important crops, causing annual losses amounting to billions of dollars. Accurate identification of these pathogens is crucial for the implementation of effective management strategies. Various methods are available for nematode species identification; however, some rely on trained taxonomists (morphological methods), specific stages of the nematode (isoenzyme electrophoresis and perineal pattern analysis) or require costly equipment and reagents (conventional or real-time polymerase chain reaction). Loop-mediated isothermal amplification is a molecular technique with the potential to offer a precise, simple, and relatively affordable diagnosis of nematode species. Although widely utilized in microbiology, human and veterinary medicine, its application in plant nematology remains relatively unexplored. This article presents a comprehensive review of the loop-mediated isothermal amplification technique, existing protocols for plant-parasitic nematode diagnosis, and the future prospects for harnessing this method in the field of plant nematology. [ABSTRACT FROM AUTHOR]

Potato (Solanum tuberosum L.) is a well-known food crop that is regarded as an important component in the worldwide battle against hunger and malnutrition. Root-knot nematodes (RKN), Meloidogyne species, are a serious limitation in the potato industry. Potato, being a tuberous crop, yield reduction is mainly due to tuber quality and quantity. In order to evaluate the response of five commercial potato cultivars, viz 'Buffelspoort 1', 'Hertha', 'Larnoma', 'Mnandi' and 'Up-to-date' to two RKN species, viz M. enterolobii and M. javanica; pot experiments were conducted under net house conditions. Ten separate experiments, each with treatments: 0, 500, 1500, 2500 and 3500 eggs + second-stage juveniles (J2), were arranged in a randomized complete block design (RCBD) with five replicates. Fifty-six days after inoculation, nematode effect on plant yield was evaluated. Potato tubers were assessed for root galls, and nematodes reproductive factor (RF) was computed. There were significant differences amongst treatments on the following potato growth parameters: plant height, stem diameter, chlorophyll content, number of tubers and tuber weight in both M. enterolobii and M. javanica (P ≤ 0.05). The RF was above unity (one) in all potato cultivars for both M. enterolobii and M. javanica; with M. enterolobii showing more aggressiveness compared to M. javanica. Further, cultivars 'Buffelspoort 1' and 'Hertha' showed the highest susceptibility, whilst cultivar 'Mnandi' showed the least susceptibility. Infection of potato cultivars by the nematodes had severe effects on growth parameters of all the cultivars. Results suggested that all five commercial potato cultivars were susceptible to M. enterolobii and M. javanica. Thus, there is an urgent need for RKN management intervention in the aforementioned cultivars. [ABSTRACT FROM AUTHOR]

Citrus slow decline is a slow developing disease occurring in citrus orchards rendering the citrus orchards uneconomical in a decade or two. Causal agents have not been identified and therefore a study was initiated to identify parameters or combination of parameters that could be useful in early detection of the disease. Four citrus orchards in Mpumalanga Province, South Africa, were identified where citrus slow disease decline was present. Twenty trees of each of the three disease categories including healthy, slight sick and sick trees, were randomly selected and sampled in each orchard. Among the many parameters measured, nematode communities were evaluated as they might show differences between the three tree categories. Results showed that Tylenchulus semipenetrans was the most abundant nematode species present in the three tree categories making up more than 90% of the nematode communities. Nine other plant-parasitic and 21 free-living nematodes were identified among the three tree categories with Acrobeloides being the most abundant nematode genus followed by Prismatolaimus. Among the feeding groups, 73% belonged to bacterivores followed by about 10% to the fungivores. Metabolic foot prints for the three tree categories were very small and closely together in the depleted and degraded quadrat. [ABSTRACT FROM AUTHOR]

Plants grown without soil are believed to be less affected by soilborne diseases. However, in a commercial greenhouse in Ethiopia's Rift valley, Lavender plants grown in hydroponic showed signs of severe stunting and galled roots. To identify the cause of the problem, root samples were taken. From these samples, single egg masses were obtained and used as inoculum for tomato cv. Moneymaker seedlings. The resulting seedlings were grown to produce a pure culture. DNA was extracted from second-stage juveniles (J2) from sixteen isolates derived from pure cultures and amplified the 28S rRNA and NADH dehydrogenase subunit 5 (Nad5) region of the mtDNA. The 28S rRNA and Nad5 were sequenced for two and five randomly selected isolates. A BLAST search of 28S rRNA sequences at NCBI showed a 98.34% sequence homology with known sequences of Meloidogyne javanica isolates. Moreover, Nad5 gene analysis, female perennial pattern, and the phylogenetic trees further confirmed the correct identification of this species. This is the first report of a nematode infecting plants growing in a hydroponic greenhouse in Ethiopia. Therefore, isolating any potential contaminants of the potting media for future lavender production are important. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of biostimulants derived from Streptomyces avermitilis metabolites on entomopathogenic nematodes: Steinernema carpocapsae, Steinernema feltiae, and Heterorhabditis bacteriophora, obtained from the soil of several Miscanthus × giganteus plantations in 2020–2023. The nematodes were isolated, identified, and cultured using live insects (the greater wax moth Galleria mellonella). Three preparations containing biostimulants – Charkor, Stimpo, and Regoplant, were tested for compatibility with entomopathogenic and plant parasitic nematodes. Their effect on nematode survival was evaluated using the Petri dish test. The study showed that the effect of biostimulants on the survival of nematodes depended on the concentration of aversectin contained in the evaluated preparations. Stimpo and Regoplant had an adverse effect on plant parasitic nematodes. The highest G. mellonella mortality was observed at the higher dose of Charkor (0.4%), and the lowest at the lower dose of Regoplant (1.22%). The study showed that the virulence of the nematodes decreased after 48 hours of incubation in Regoplant and Stimpo solutions containing aversectin. The degree of interaction between nematodes depended on the nematode species, trophic preferences, and the concentration of active ingredients in the preparations. This conclusion is crucial for the selection of appropriate types of entomopathogenic nematodes and the application rate of plant parasitic nematodes in the assessment of their short- and long-term spread, persistence, and recycling in field conditions. [ABSTRACT FROM AUTHOR]

Mermithid parasitoids are well known to infect spiders; however, their impact on hosts and their taxonomic identity are still poorly analyzed. We present the first record of a mermithid nematode infection in the spider genera Piratula (Lycosidae) and Coelotes (Agelenidae), and in the species Alopecosa pulverulenta and Pardosa paludicola (Lycosidae). We describe the maldevelopment of the spiders' female genitalia induced by the parasitoid and summarize data on the impact of nematode parasitoids on spider development and behaviour. Phylogenetic analysis, based on the 18S rDNA, showed that spider parasitoidism arose independently in different branches of the phylogenetic tree of the family Mermithidae. [ABSTRACT FROM AUTHOR]

Complex cross-talk occurs between gastrointestinal nematodes and gut symbiotic microbiota, with consequences for animal metabolism. To investigate the connection between methane production and endoparasites, this study evaluated the effect of mixed infection with Haemonchus contortus and Trichostrongylus colubriformis on methanogenic and methanotrophic community in rumen microbiota of lambs using shotgun metagenomic and real-time quantitative PCR (qPCR). The rumen content was collected from six Santa Inês lambs, (7 months old) before and after 42 days infection by esophageal tube. The metagenomic analysis showed that the infection affected the microbial community structure leading to decreased abundance of methanotrophs bacteria, i.e. α-proteobacteria and β-proteobacteria, anaerobic methanotrophic archaea (ANME), protozoa, sulfate-reducing bacteria, syntrophic bacteria with methanogens, geobacter, and genes related to pyruvate, fatty acid, nitrogen, and sulfur metabolisms, ribulose monophosphate cycle, and Entner–Doudoroff Pathway. Additionally, the abundance of methanogenic archaea and the mcrA gene did not change. The co-occurrence networks enabled us to identify the interactions between each taxon in microbial communities and to determine the reshaping of rumen microbiome associations by gastrointestinal nematode infection. Besides, the correlation between ANMEs was lower in the animal's postinfection. Our findings suggest that gastrointestinal parasites potentially lead to decreased methanotrophic metabolism-related microorganisms and genes. [ABSTRACT FROM AUTHOR]

Parthenium hysterophorus, a noxious weed of tropical America, had relocated to Indian plains and rapidly encroached on northwestern Himalayas Mountain regions. Earlier, the plant was primarily found in wastelands, but it now thrives in cultivated fields, pastures, and roadsides. Parthenium weed threatens human and animal health, destroys vegetation, lowers the diversity of native plant groups and causes significant financial damage to individuals and their significance in numerous nations worldwide. Parthenin, a sesquiterpene lactone found in P. hysterophorus, is harmful to livestock and poses a serious health risk to people, e.g., dermatitis and skin rashes, emaciation, tissue rupturing, internal organ haemorrhages and death are the hazardous side effects. Several studies are being conducted to determine the most efficient and reasonable method to control this harmful weed worldwide, including physical, chemical and biological ones. The study revealed that biocontrol of P. hysterophorus was a costeffective, safe and viable technique and poses no threat to non-target organisms, environment and biodiversity, e.g., some allelopathic plants are used to curb the growth of congress grass. The combined effects of biocontrol agents like insects, fungi, nematodes, snails, slugs, and competitive plants decrease the density and vigour of congress grass and increase its production. The work done over the past 20 years on screening and evaluating both insect and fungal agents and the actual and potential employment of natural enemies as traditional biological control agents has been discussed. The study concludes that biological control, because of its affordability, environmental safety and sustainability, could be a significant constituent of an effective strategy for managing weed. [ABSTRACT FROM AUTHOR]

Helminth infections are unavoidable in outdoor grazing systems, but must be managed and controlled effectively as they lead to significant production losses and welfare issues. Control has typically relied on a small number of broad-spectrum anthelmintics, but resistance is now widespread and threatens the sustainability of farming. Detection of anthelmintic resistance (AR) has long relied on microscopy-based tests which lack sensitivity and do not offer species-specific information. Next-generation sequencing (NGS) has revolutionized our understanding of the genetic basis of AR in recent years. This has now facilitated the development of improved sequencing-based molecular diagnostics which now can offer for the first time multidrug and multispecies detection in a single assay. Helminth infections in grazing ruminants are a major issue for livestock farming globally, but are unavoidable in outdoor grazing systems and must be effectively managed to avoid deleterious effects to animal health, and productivity. Next-generation sequencing (NGS) technologies are transforming our understanding of the genetic basis of anthelmintic resistance (AR) and epidemiological studies of ruminant gastrointestinal parasites. They also have the potential to not only help develop and validate molecular diagnostic tests but to be directly used in routine diagnostics integrating species-specific identification and AR into a single test. Here, we review how these developments have opened the pathway for the development of multi-AR and multispecies identification in a single test, with widespread implications for sustainable livestock farming for the future. [ABSTRACT FROM AUTHOR]

The white-bellied pangolins (Phataginus tricuspis) harbour ecto- and endo-parasites. In this study we compared the bioaccumulation potentials of metadavinae cestode and stongylondes nematode parasites for trace metals in the intestine, and the lipid profile in the liver of infected and uninfected P. tricuspis sampled from Epe Local Government Area, Lagos State, Nigeria. Trace metal concentrations were determined in the pangolin and its intestinal parasites using a Flame Atomic Absorption Spectrometer. Total cholesterol levels in the infected and uninfected pangolin were determined using the enzymatic endpoint method. The concentrations of Al, Cd, and Cr were higher in the infected intestines, while Ba, Fe, and Zn were higher in the uninfected intestines. The levels of lipid profile in the infected intestine were comparatively low. The average level of cholesterol (CHOL) in the infected intestine was 0.87 mg/dL, while the levels of triglycerides (TRIG), high-density lipoproteins (HDL), and low-density lipoproteins (LDL) were all below 0.4 mg/dL. The concentrations of the lipid profile CHOL and HDL in the uninfected intestines were higher than the concentrations observed in the infected counterparts. The concentrations of CHOL, HDL, and LDL were 2 mg/dL, 1.7 mg/dL, and 0.85 mg/dL respectively, while TRIG below 0.35 mg/dL. The concentrations of trace metals detected in the tissues of strongylondes nematodes showed significant bioaccumulation factors in the order of Mn (28.6)> Zn (9.7)> Ba (5.2)> Cd (3.5)> Cr (2.9)> Al (1.3). Cestode parasites are good biodepurative agents. The nematodes in this study exhibited notable biodepuration superiority. Strongyloides spp. may be a reliable bioindicator of the metal burden in P. tricuspis. This provides a reliable ecotoxicological prognosis for proactive remediations and decisions by lawmakers to make pragmatic plans and policies toward sustainable conservation of P. tricuspis. [ABSTRACT FROM AUTHOR]

Summary: The present study describes two new Ditylenchus species, isolated from the growing medium of Rhododendron simsii imported from Japan, at the Ningbo plant quarantine laboratory, Ningbo, P.R. China. Ditylenchus parvicauda n. sp. is an amphimictic species. Females have six incisures in the lateral fields, a medium length slim body, a short delicate stylet with asymmetrical stylet knobs, the secretory-excretory (S-E) pore located posterior to the isthmus and in the anterior region of the basal pharyngeal bulb, a posteriorly located vulva (V = 80.9-83.0), post-uterine sac (PUS) tube-like, and the tail cylindrical, tapering gradually towards finely rounded terminus. Males are similar to females in general morphology and have 10.1-14.9 μ m long spicules. The second new species, D. gracicauda n. sp. is characterised by having a long and slender body, the presence of a vulval flap, four lines in the lateral field, a narrow and low lip region not offset, the S-E pore located posterior to the isthmus but not in the anterior region of the basal pharyngeal bulb, a posteriorly located vulva (V = 71.1-76.2), a short post-vulval uterine sac short (4.5-9.2 μ m), and the tail slender, tapering gradually towards finely rounded to wedge-shaped terminus. The two new species were also characterised molecularly using 18S, ITS and the D2-D3 expansion segments of 28S rRNA genes. Our phylogenetic analyses showed their independent place among available Ditylenchus species. Several Ditylenchus species are regulated pests, and the introduction of these species into a new environment may result in diseases among native plants or vegetation in the area. Therefore, careful attention must be directed towards newly discovered species, particularly those under quarantine observation. [ABSTRACT FROM AUTHOR]

Summary: The red ring nematode, Bursaphelenchus cocophilus , vectored by the South American palm weevil, Rhynchophorus palmarum , is the causal agent of red ring disease in coconut and other palms in countries of Central and South America. The populations of B. cocophilus collected in the states of Guerrero and Tabasco, Mexico, were molecularly characterised using the D2-D3 expansion segments of 28S rRNA, ITS rRNA and COI gene sequences. Mexican B. cocophilus populations were molecularly different from other Central and South American populations. Comparative analysis of available rRNA sequences obtained from several countries showed that B. cocophilus consists of molecularly different populations and its species structure is likely congruent with that of the beetle vector. Conventional PCR, real-time PCR and recombinase polymerase amplification (RPA) with lateral flow dipstick (LF) assays have been developed for the identification of the red ring nematode in this study. The specificity of the ITS rRNA primers in the assays were examined using B. cocophilus and other 15 species of family Aphelenchoididae. Detection sensitivity levels, determined by using a dilution series of B. cocophilus extracts, was 0.13 nematode per reaction tube for real-time PCR and 0.25 nematode per reaction tube for conventional PCR and LF-RPA assays. The application of the LF-RPA assay has great potential for diagnosing infestation of this species with a minimal laboratory infrastructure. [ABSTRACT FROM AUTHOR]

Background and aims: The false-root knot nematode (Nacobbus spp.) comprises polyphagous species, with pepper (Capsicum annuum) being one of the most affected crops. Due to the lack of resistant pepper genotypes, we compared the responses of different commercial cultivars to identify possible plant defence mechanisms against N. celatus. M&M: Nematodes from Río Cuarto (Córdoba Province) and Lisandro Olmos (Buenos Aires Province) were inoculated on pepper cultivars: California Wonder (control), Fyuco INTA, Yatasto, and Fenomeno RZ. Plants were grown under a greenhouse and galls were analysed by histopathological techniques. Results: The roots of the commercial cultivars showed the typical morpho-anatomical alterations induced by N. celatus: gall formation, hyperplasia reactions, development of syncytia in the central cylinder and disorganisation of vascular tissues. Syncytial cells in contact with females of nematodes from Lisandro Olmos showed a defence reaction by Fyuco INTA, whereas feeding sites in Fenomeno RZ did not denote high metabolic activity in nematodes of both origins. Conclusions: The different responses observed between populations and/or hosts demonstrate the importance of considering nematodes from different geographical origins when testing plant material for tolerance and/or resistance to N. celatus. Studies of this nature are necessary since they facilitate a more in-depth understanding of the parasite-plant interaction. [ABSTRACT FROM AUTHOR]

Infections with gastrointestinal nematodes (GINs) reduce the economic efficiency of sheep operations and compromise animal welfare. Understanding the host's response to GIN infection can help producers identify animals that are naturally resistant to infection. The objective of this study was to characterize the hepatic transcriptome of sheep that had been naturally exposed to GIN parasites. The hepatic transcriptome was studied using RNA-Sequencing technology in animals characterized as high (n = 5) or medium (n = 6) based on their innate immune acute-phase (AP) response phenotype compared with uninfected controls (n = 4), and with biased antibody-mediated (AbMR, n = 5) or cell-mediated (CMR, n = 5) adaptive immune responsiveness compared to uninfected controls (n = 3). Following the assessment of sheep selected for innate responses, 0, 136, and 167 genes were differentially expressed (DE) between high- and medium-responding animals, high-responding and uninfected control animals, and medium-responding and uninfected control animals, respectively (false discovery rate (FDR) < 0.05, and fold change |FC| > 2). When adaptive immune responses were assessed, 0, 53, and 57 genes were DE between antibody- and cell-biased animals, antibody-biased and uninfected control animals, and cell-biased and uninfected control animals, respectively (FDR < 0.05, |FC| > 2). Functional analyses identified enriched gene ontology (GO) terms and metabolic pathways related to the innate immune response and energy metabolism. Six functional candidate genes were identified for further functional and validation studies to better understand the underlying biological mechanisms of host responses to GINs. These, in turn, can potentially help improve decision making and management practices to increase the overall host immune response to GIN infection. [ABSTRACT FROM AUTHOR]

Beech leaf disease (BLD) is a newly emerging disease in North America that affects American beech (Fagus grandifolia). It is increasingly recognized that BLD is caused by a subspecies of the anguinid nematode Litylenchus crenatae subsp. mccannii (hereafter L. crenatae), which is likely native to East Asia. How nematode infestation of leaves affects the leaf microbiome and whether changes in the microbiome could contribute to BLD symptoms remain uncertain. In this study, we examined bacterial and fungal communities associated with the leaves of F. grandifolia across nine sites in Ohio and Pennsylvania that were either symptomatic or asymptomatic for BLD and used qPCR to measure relative nematode infestation levels. We found significantly higher levels of infestation at sites visibly symptomatic for BLD. Low levels of nematode infestation were also observed at asymptomatic sites, which suggests that nematodes can be present without visible symptoms evident. Bacterial and fungal communities were significant ly affected by sampling site and symptomology, but only fungal communities were affected by nematode presence alone. We found many significant indicators of both bacteria and fungi related to symptoms of BLD, with taxa generally occurring in both asymptomatic and symptomatic leaves, suggesting that microbes are not responsible for BLD but could act as opportunistic pathogens. Of particular interest was the fungal genus Erysiphe, which is common in the Fagaceae and is reported to overwinter in buds --a strategy consistent with L. crenatae. The specific role microbes play in opportunistic infection of leaves affected by L. crenatae will require additional study. [ABSTRACT FROM AUTHOR]

The question, when ants first appeared, remains unanswered. However, images of ants in Burmese amber show that some extinct types existed back then. By the mid-Cenozoic, most fossil ants could be assigned to extant genera. The present work examines ancient associations between ants and other organisms based on fossils in amber. Topics include fungal associates, interactions with higher plants, associations between ants and arachnids, ants bringing food to the colony, insect parasites and predators, nematode parasites, ants visiting flowers, ant mimics and gut microbes in ants. All specimens included in the present work are listed with the amber source, present location, published accounts and accession numbers of those in the Poinar amber collection (PAC). [ABSTRACT FROM AUTHOR]

This study was conducted to determine whether the macroalgae Ulva papenfussi and Ulva nematoidea could be alternatives for preventing Litopenaeus vannamei vibriosis caused by the bacterium Vibrio parahaemolyticus. Phytochemical screening was performed on methanolic extracts to qualitatively determine the main groups of bioactive compounds, previous to an in vitro antibacterial test against V. parahaemolitycus. Phenols, polyphenols, flavonoids, and the high presence of carbohydrates were found in both macroalgae. U. papenfussi showed more presence of lipids and alkaloids than U. nematoidea. Macroalgae extracts prepared (v:v) with a 1:1 methanol: dichloromethane solvent was used for the in vitro test using the disc diffusion method (MDD). Filter paper discs impregnated with 1.0, 1.5, 2.0, 3.0, and 4.0 mg of the extracts showed antibacterial activity against V. Parahaemolitycus in a dose-dependent manner in both macroalgae. The inhibition zone varied significantly (p < 0.05) from 8.33 ± 0.12 to 11.41 ± 0.73 mm for 1 to 3 mg of extract levels, respectively. In conclusion, both macroalgae have antibacterial activity in their crude extracts against this bacteria. It is suggested to evaluate it as a feed additive for L. vannamei. This study is the first report on a phytochemical screening and antibacterial activity of these macroalgae against V. parahaemolyticus. [ABSTRACT FROM AUTHOR]

The Sparganophilidae are one of the few non monotypic families of earthworms with no reported parasites, pathogens, or endosymbionts. While conducting a survey of the Sparganophilidae across North America we took the opportunity to examine a population from an exposed lakebed for endoparasites. Worms were dissected after anesthetizing them in clove water; 4 of 24 worms (16%) harboured a new species of Stomatophora (Apicomplexa: Monocystidae) and one worm harbored a juvenile Rhabditida (Nematoda). Based on these collections we described Stomatophora benhami n. sp. [ABSTRACT FROM AUTHOR]

Clear variation in the pathogenicity and epidemiology of gastrointestinal nematodes and sensitivity to anthelminthic drugs require precise epidemiological information for such worms. Our work is the first effort to detect the abomasal nematodes (Haemonchus spp, Ostertagia ostertagi) in calves in Mosul, Iraq through amplification of rDNA ITS1 and ITS 2 regions. Four hundred and eighty (480) faecal samples were collected from 35 private calf herds between October 2021 and April 2022. Ages, origins of the herds, size of the herds, and gender were recorded. Microscopic examination and larval culture were conducted. Specified primers were used for molecular identification. The study showed a 50.6% total prevalence of gastrointestinal nematodes in calves. Haemonchus spp. and Ostertagia ostertagi rates were 62.13%, and 60.9%, respectively. The percentages of L3 of Haemonchus spp. and Ostertagia spp. were 32% and 14% respectively. Polymerase chain reaction (PCR) showed reaction products of 321 bp, and 257 bp for studied parasites, respectively. In conclusion, classical laboratory tools may be unable to identify precisely the species and subsequently, minimise the comprehension of parasitic species that circulate in animal populations. Molecular detection is a rapid, highly sensitive, specific and cost-effective procedure that accurately identifies parasite species. [ABSTRACT FROM AUTHOR]

Introduction: The current experiment investigated the multifaceted effects induced by microplastics and the statin Lipitor on marine benthic nematodes. Methods: The nematodes were exposed to a single polystyrene and polyvinyl chlorides (both at 1 mg.kg-1 Dry Weight) and two Lipitor concentrations (0.1 and 1 mg.l-1), as well as to a mixture of both types of pollutants, for 30 days. Results: The results highlighted a significant decrease in the abundance, individual biomass, and diversity of nematodes directly with the addition of polyvinyl chlorides and/or Lipitor. These treatments induced a greater mortality rate among microvores and diatom feeders compared to other feeding types of nematodes. Discussion: The nematofauna underwent a strong restructuring phase following exposure to microplastics and Lipitor when added alone, leading to the disappearance of sensitive species and their replacement by more tolerant taxa. The toxicity of Lipitor is attenuated by the physical bonding with polystyrene when added to a mixture and has no negative effect on marine nematode species. [ABSTRACT FROM AUTHOR]

Lymphatic filariasis is caused by parasitic nematodes and is a leading cause of disability worldwide. Many filarial worms contain the bacterium Wolbachia as an obligate endosymbiont. RNA sequencing is a common technique used to study their molecular relationships and to identify potential drug targets against the nematode and bacteria. Ribosomal RNA (rRNA) is the most abundant RNA species, accounting for 80-90% of the RNA in a sample. To reduce sequencing costs, it is necessary to remove ribosomal reads through poly-A enrichment or ribosomal depletion. Bacterial RNA does not contain a poly-A tail, making it difficult to sequence both the nematode and Wolbachia from the same library preparation using standard poly-A selection. Ribosomal depletion can utilize species-specific oligonucleotide probes to remove rRNA through pull-down or degradation methods. While species-specific probes are commercially available for many commonly studied model organisms, there are currently limited depletion options for filarial parasites. Here, we performed total RNA sequencing from Brugia malayi containing the Wolbachia symbiont (wBm) and designed ssDNA depletion probes against their rRNA sequences. We compared the total RNA library to poly-A enriched, Terminator 5'-Phosphate-Dependent Exonuclease treated, NEBNext Human/Bacteria rRNA depleted and our custom nematode probe depleted libraries. The custom nematode depletion library had the lowest percentage of ribosomal reads across all methods, with a 300-fold decrease in rRNA when compared to the total RNA library. The nematode depletion libraries also contained the highest percentage of Wolbachia mRNA reads, resulting in a 16-1,000-fold increase in bacterial reads compared to the other enrichment and depletion methods. Finally, we found that the Brugia malayi depletion probes can remove rRNA from the filarial worm Dirofilaria immitis and the majority of rRNA from the more distantly related free living nematode Caenorhabditis elegans. These custom filarial probes will allow for future dual RNA-seq experiments between nematodes and their bacterial symbionts from a single sequencing library. [ABSTRACT FROM AUTHOR]

Heterodera schachtii (Schmidt, 1871) (Nematoda: Heteroderidae) is one of the most widespread plant-parasitic nematodes (PPNs) associated with cabbages, which cause severe yield losses in cruciferous vegetables. This study aimed to improve the current understanding of the prevalence and detection of H. schachtii in the cabbage-growing areas of Niğde Province, Türkiye. Field surveys were conducted between November and December 2021, and 100 soil samples were collected immediately after cabbage harvesting. Heterodera schachtii populations were identified by morphological and morphometric methods along with Internal Transcribed Spacer of the ribosomal region (ITS-rDNA) and Cytochrome Oxidase Subunit (COI-mtDNA) sequencing. The mean body length of H. schachtii was 463 ± 7 μm, while stylet and hyaline length ranged between 20.7–27.8 μm and 20.1–32.1 μm, respectively. Nearly half of the surveyed areas were infested with H. schachtii with a 41% incidence rate. However, the Merkez District had the highest proportion of infested fields with an over 51% incidence rate. The population density was determined in 41 samples with a mean of 79.5 cysts per 250 g of soil. These results will help to determine the control and management strategies of H. schachtii. [ABSTRACT FROM AUTHOR]

The nematode family Aphelenchoididiae is considered fungal-feeding, predatory, or root hair feeders. Some members of this family are universally present in agricultural landscapes and are an integral part of soil health and conservation studies. In the present soil nematode biodiversity survey, we detected four species of the genera Aphelenchus, Aphelenchoides, and Robustodorus. Because fungal-feeding nematodes from southern Alberta have not previously been reported, we conducted a detailed morphological and molecular investigation, identifying these species as Aphelenchus avenae, Aphelenchoides limberi, Aphelenchoides prairiensis n. sp. and Robustodorus paramegadorus n. sp. The first two species we document as new records from southern Alberta, whereas A. prairiensis n. sp. and R. paramegadorus n. sp. we describe in detail as new taxa. Briefly, A. prairiensis n. sp. is an amphimictic species having 4 lateral lines; hemispherical anteriorly flattened lip region; delicate stylet and swelling-like stylet knobs; excretory pore at the posterior edge of nerve ring. Female tail conical, gradually tapering towards a truncated end with single mucro. Spicule 23.0 (20.0–25.0) µm long having elongated rounded condylus, small, blunt conical rostrum, and lamina that gradually tapers towards the rounded distal end; three pairs of caudal papillae were present on the male tail. Robustodorus paramegadorus n. sp., is a parthenogenetic species with 3 lines in the lateral fields; lip region rounded, anteriorly flattened; stylet robust, with knobs rounded to bean-shaped; excretory pore located posterior to nerve ring; reproductive components were quite indiscernible with a short 24.0 (18.0–27.0) µm post-vulval uterine sac; tail conical, ending with pointed to wedge-shaped tip. We performed molecular characterizations for each species and constructed phylogenetic trees to study the phylogenetic relationship of these aphelenchid species. The discovery of A. prairiensis n. sp. and R. paramegadorus n. sp. indicates that soil nematode diversity is relatively unexplored in southern Alberta. The findings of this study will significantly enhance the identification processes and may contribute towards future soil health and biodiversity efforts. [ABSTRACT FROM AUTHOR]

We propose a framework that integrates norm entrepreneurship from human society into the dynamics of an agent society. Most work in agent coordination in a distributed environment studies norms that are provided to agents as part of their specification or distributed from centralised agents. Exploring an alternate perspective, we focus on peer-to-peer interaction by providing the agents with the freedom to initiate norm creation in demanding situations like a potential interference. This paper explores the concept of norm entrepreneurship through proactive establishment and emergence of norms by agents. A common approach in prior work focuses on coordination problems that are reduced to simple game theory models involving the simultaneous performance of a single action by each agent. Instead, we define the concept of a local coordination plan (LCP), which is a sequence of actions from each agent to cope with an interference in their normal course of action. We identify LCPs across various scenarios and abstract these plans using coordination state machines (CSMs). A coordination state machine contains a separate state machine for each agent where the states encapsulate the potentially constrained and suboptimal movement options agents have at a given time. We also explore how multiple LCPs lead to a coordination state machine of the same format and how a coordination state machine can abstract across multiple scenarios. [ABSTRACT FROM AUTHOR]