Journal of nematology最新文献

{"title":"Description and molecular characterization of <i>Geraldius jejuensis</i> n. sp. (Nematoda: Chambersiellidae) from Korea.","authors":"Abraham Okki Mwamula, Chang-Hwan Bae, Dae Geun Lee, Yi Seul Kim, Yeong-Don Lee, Dong Woon Lee","doi":"10.2478/jofnem-2025-0023","DOIUrl":"10.2478/jofnem-2025-0023","url":null,"abstract":"<p><p>A new species of the genus Geraldius isolated from the wood of a dead black pine tree is characterized using morphological data and molecular DNA barcodes. <i>Geraldius jejuensis</i> n. sp. is characterized by its lateral fields with two incisures; lip region conoid to rounded and continuous with body; hemizonid and excretory pore located posterior to nerve ring; excretory pore opening just at the beginning of hemizonid or within the contour of hemizonid; vulva a transverse slit in ventral view; opening in a depression, creating a circular profile in lateral view; rectum 1.4 to 1.7 times longer than anal body diameter; phasmids located 55.0 to 78.5 μm from anal opening; tail elongated, 146.0 to 177.0 μm long; gubernaculum 27.0 to 33.5 μm long, caudal papillae arrangement of seven pairs pre-cloacal, two adcloacal, and six post-cloacal; and three additional midventral papillae on anterior cloacal lip. The new species was compared with the three known species of the genus, including <i>G. bakeri, G. galapagoensis</i> and <i>G. inserrai</i>. The phylogenetic relationships among species were reconstructed using 18S-rRNA and 28S-rRNA gene sequences. Inferences from both genes corroborate the close morphological relationships between <i>Geraldius</i> and <i>Diastolaimus</i>.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250023"},"PeriodicalIF":1.4,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12181934/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144475662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genome Announcement: Further Improved Genome Assembly of <i>Parapristionchus giblindavisi</i>.","authors":"Waltraud Röseler, Kohta Yoshida, Christian Rödelsperger","doi":"10.2478/jofnem-2025-0026","DOIUrl":"10.2478/jofnem-2025-0026","url":null,"abstract":"<p><p>Nematodes such as <i>Caenorhabditis elegans</i> and <i>Pristionchus pacificus</i> are powerful models for associating phenotypes to genotypes. However, exploring the evolution of identified genetic loci requires a robust phylogenomic framework. Here, we present an updated genome of the nematode <i>Parapristionchus giblindavisi</i> which is the only known member of the sister group of <i>Pristionchus</i>. Reassembly of previously generated long read sequencing data combined with new Hi-C data resulted in a near chromosome-scale genome assembly spanning 302.5Mb. The Hi-C contact map, karyotyping data and comparative genomic analysis support an organization of the <i>P. giblindavisi</i> genome into six chromosomes, whereby all autosomes correspond to individual Nigon elements and the sex chromosome represents a fusion of Nigon elements D and X. The further improved <i>P. giblindavisi</i> genome will be useful as an outgroup for dating and polarizing lineage-specific genomic signatures.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250026"},"PeriodicalIF":1.4,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12181933/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144475664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to: Nematicidal Properties of Chitosan Nanoformulation.","authors":"R Mouniga, B Anita, A Lakshmanan, A Shanthi, G Karthikeyan","doi":"10.2478/jofnem-2025-0022","DOIUrl":"https://doi.org/10.2478/jofnem-2025-0022","url":null,"abstract":"<p><p>[This corrects the article DOI: 10.2478/jofnem-2023-0033.].</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250022"},"PeriodicalIF":1.4,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12173449/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144317155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nematocidal activity of fungal filtrates on eggs and juveniles of five species of sedentary endoparasitic nematodes.","authors":"B Jumbam, A B Peetz, V S Kunwar, L Zhang, I A Zasada, M C Aime","doi":"10.2478/jofnem-2025-0018","DOIUrl":"10.2478/jofnem-2025-0018","url":null,"abstract":"<p><p>Research efforts are needed to develop new biocontrol strategies against plant-parasitic nematodes (PPNs) to replace chemicals and maintain sustainable crop production. In this study, filtrates obtained from fungi isolated from cyst nematodes (Heteroderidae) were evaluated for activity against eggs and second-stage juveniles (J2) of five PPNs: <i>Globdera ellingtonae, Heterodera glycines, Meloidogyne incognita</i>, <i>M. hapla</i>, and <i>M. chitwoodi</i>. Initially, filtrates of 42 fungal isolates were evaluated for effects on <i>G. ellingtonae</i> and <i>H. glycines</i> egg viability. After the initial screening, six of the fungal isolates were selected for further evaluation against additional PPN eggs and J2 based upon evidence of usage in other studies, fast growth, and frequency of isolation. Filtrates from <i>Alternaria tenuissima</i> JB217, <i>Fusarium acaciae-mearnsii</i> JB201, <i>Purpureocillium lilacinum</i> JB209, and <i>Trichoderma virens</i> JB98 reduced <i>H. glycines</i> egg viability by >80%. <i>Aureobasium</i> sp. JB70, <i>F. proliferatum</i> JB173, and <i>P. lilacinum</i> JB209 reduced <i>G. ellingtonae</i> egg viability by >50% but had negligible effect on the J2 stage of this nematode. Filtrate from <i>F. acaciae-mearnsii</i> JB201was the most lethal against PPNs, immobilizing ~100% of J2 of all nematode species while filtrate from <i>A. tenuissima</i> JB217 only immobilized J2 of <i>G. ellingtonae, M. chitwoodi</i>, and <i>M. hapla</i>. These fungal filtrates are therefore promising alternative sources of natural bioactive substances for the potential management of PPNs.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250018"},"PeriodicalIF":2.0,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12136676/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First Record of Mermithidae (Enoplea: Mermithida) Parasitizing <i>Philaenus spumarius</i> (Hemiptera: Aphrophoridae) in Central Italy.","authors":"Anita Nencioni, Gaia Bigiotti, Elisabetta Gargani, Patrizia Sacchetti, Agostino Strangi, Ilaria Cutino","doi":"10.2478/jofnem-2025-0019","DOIUrl":"10.2478/jofnem-2025-0019","url":null,"abstract":"<p><p><i>Philaenus spumarius</i> specimens were found naturally parasitized by Mermithidae nematodes in Central Italy. Nematodes infected all spittlebug instars, showing a highly variable parasitization rate according to sampling locations. Molecular analysis highlighted the presence of two distinct species that are apparently not cohabitant in the same site. However, complete taxonomic identification will occur when adult nematodes are obtained. Further research is needed to identify these two putative nematode species and to understand their ecological requirements. Furthermore, new studies aimed to elucidate the relationship between <i>P. spumarius</i> and Mermithidae nematodes, as well as the role of these parasites in regulating spittlebug populations, can be useful in identifying potential natural enemies for pest control. To our knowledge, this is the first report of Mermithidae infecting <i>P. spumarius</i> in Europe.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250019"},"PeriodicalIF":1.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12136675/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225734","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Properties of Enhanced Calcium-alginate Beads as a Formulation for Disseminating the Entomopathogenic Nematodes <i>Heterorhabditis bacteriophora</i>, <i>Steinernema carpocapase</i>, and <i>Steinernema feltiae</i>.","authors":"Reyhaneh Darsouei, Javad Karimi, Lukasz L Stelinski","doi":"10.2478/jofnem-2025-0020","DOIUrl":"10.2478/jofnem-2025-0020","url":null,"abstract":"<p><p>Calcium alginate beads are one of the substrates used to formulate and store the infective juveniles (IJs) of entomopathogenic nematodes (EPNs). Due to the sensitivity of EPNs to heat, cooling devices are needed to transfer them from the production site to the field or greenhouse. Therefore, it is important to develop a formulation that can be stored at room temperature. The hypothesis of this study was that nematodes formulated in alginate beads would be more stable at room temperature than in sterile water. To compare and select the optimal conditions, formulations were tested at two temperatures: 25 and 8 Celsius (ºC). The formulation included sodium alginate (1.5-1.75%), glycerin, nematode suspension in distilled water (~15,000 IJs), food coloring, and two proprietary water-absorbent compounds. The suspension was added to CaCl₂ (8:2 CaCl₂: glycerin) to create calcium alginate beads. The beads were stored at 8 ºC and 25ºC with a control treatment consisted of sterile water. The study measured survival, reproduction rate, and infectivity of <i>Heterorhabditis bacteriophora, Steinernema carpocapsae</i>, and <i>S. feltiae</i> IJs in calcium alginate beads over time (1-180 days post-formulation). The survival rate of IJs in bead formulations was significantly higher than in the water control treatment. <i>H. bacteriophora</i> experienced higher survival at 25ºC, while <i>S. carpocapsae</i> experienced higher survival at 8ºC. <i>S. feltiae's</i> survival was not affected by temperature. The pathogenicity of EPNs did not decrease over time. Calcium alginate effectively encapsulated living IJs of various EPN species, keeping them alive for up to three months at room temperature. These results suggest that alginate beads are a suitable material for EPNs formulation. Further research is needed to enhance the efficacy and economic viability of these formulations.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250020"},"PeriodicalIF":1.4,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12136810/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144225736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of the newly discovered entomopathogenic nematode <i>Steinernema adamsi</i> against <i>Helicoverpa zea</i>: life stage susceptibility, UV tolerance, and field performance.","authors":"James Paul Glover, Nathan Spaulding, Justin George, Maribel Portilla, Gadi V P Reddy, Adler Dillman","doi":"10.2478/jofnem-2025-0012","DOIUrl":"https://doi.org/10.2478/jofnem-2025-0012","url":null,"abstract":"<p><p><i>Helicoverpa zea</i> is a major agricultural pest, particularly in cotton, and poses significant challenges due to its ability to develop resistance to chemical insecticides. This study evaluates the efficacy of the entomopathogenic nematode (<i>Steinernema adamsi</i>) and its mutualistic bacteria (<i>Xenorhabdus</i>) as biological control agents against <i>H. zea</i> larvae in both laboratory and field settings. In laboratory assays, mortality rates for 1^st to 4^th instars were high, ranging from 74.2% to 100%, while 5^th instars exhibited significantly lower susceptibility (<37% mortality). Pupae were completely resistant to nematode infection. The impact of UV radiation on nematode efficacy was assessed, with mortality decreasing from 100% in control conditions (0 hours of UV exposure) to 71.8% after 5 hours of UV exposure, highlighting the vulnerability of <i>S. adamsi</i> to UV degradation. In addition, <i>Xenorhabdus</i> caused 100% mortality in <i>H. zea</i> larvae when injected directly into the hemocoel, but oral toxicity was significantly lower, with 36% mortality in 7 days post-exposure. Field experiments demonstrated that the combination of <i>S. adamsi</i> with 0.05% sodium alginate (hygroscopic agent) and 0.02% Congo red (UV protectant) resulted in a significant increase in larval mortality. In field test A, where <i>S. adamsi</i> was applied in water, mortality averaged 56% with 82% EPN infection. In field test B, the combined treatment of sodium alginate and Congo red led to 98% larval mortality, although infection rates were lower and statistically non-significant. The addition of these protective agents likely enhanced the environmental stability and efficacy of the nematodes under field conditions. These findings suggest that <i>S. adamsi</i> can be an effective biological control agent for <i>H. zea</i>, particularly when combined with formulations that protect against UV radiation and desiccation. Future research should focus on optimizing nematode delivery systems to improve field efficacy under diverse environmental conditions.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250012"},"PeriodicalIF":1.4,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12020467/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144029200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reproduction of <i>Meloidogyne enterolobii</i> on Onion and Potential Yield Suppression.","authors":"Nabin Poudel, Richard F Davis, Ted McAvoy, Bhabesh Dutta, Intiaz Amin Chowdhury","doi":"10.2478/jofnem-2025-0005","DOIUrl":"10.2478/jofnem-2025-0005","url":null,"abstract":"<p><p><i>Meloidogyne enterolobii</i>, is an emerging root-knot nematode species in the southern United States. To date, no studies have evaluated the host status of onions to <i>M. enterolobii</i>. This study aimed to assess the reproduction and pathogenicity of <i>M. enterolobii</i> on onion cultivars commonly grown in Georgia. Six Vidalia onion cultivars ('Rio del Sol', 'Sapelo', 'Sweet Magnolia,' 'Tania,' 'Vidora,' and 'NUN 1011'), three red onion cultivars ('Red Duke,' 'Red Halen,' and 'Red Maiden'), and a white onion cultivar ('Monjablanca') were evaluated. Each cultivar was inoculated with 8,000 eggs of <i>M. enterolobii</i> in a repeated greenhouse trial with six replications each. Twelve weeks post-inoculation, plants were harvested to determine reproduction and pathogenicity based on the reproduction factor (Rf = final nematode population/initial nematode inoculum) and reductions in bulb and shoot weights, respectively. All tested cultivars were susceptible to <i>M. enterolobii</i>, with Rf values greater than 1, though significant differences were observed. 'Vidora' and 'Tania' exhibited the highest galling index and Rf values, while 'Sweet Magnolia' and 'Sapelo' had the lowest. All red onion cultivars showed significant reductions in weight for both bulbs and shoots, whereas among the Vidalia cultivars, only 'NUN 1011' exhibited notable reductions in bulb and shoot weights. These findings suggest that onions are suitable hosts for <i>M. enterolobii</i>, and that the nematode's reproduction and pathogenicity vary with onion type and cultivar.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250005"},"PeriodicalIF":1.4,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12016019/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144025921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluopyram or Resistant Cultivars Manage <i>Meloidogyne arenaria</i> Infestation in Virginia-Type Peanut Production.","authors":"Zane J Grabau, Sabina Budhathoki, Rebeca Sandoval Ruiz, Chang Liu","doi":"10.2478/jofnem-2025-0010","DOIUrl":"https://doi.org/10.2478/jofnem-2025-0010","url":null,"abstract":"<p><p><i>Meloidogyne arenaria</i> (peanut root-knot nematode, PRKN) is an important pest in peanut (<i>Arachis hypogea</i>) production in the United States, including specialty Virginia-type peanuts. Cultivars resistant to PRKN and nematicide application are two available methods for managing PRKN. The objectives of this study were to determine the impacts of resistant Virginia-type peanut cultivars (Georgia-19HP and TifJumbo) on (1) management of PRKN abundances and damage and (2) total free-living nematode soil abundances. A common susceptible cultivar (Bailey II) with or without in-furrow fluopyram nematicide was compared to the resistant cultivars without nematicide in field trials in Florida (2022 and 2023). Resistant cultivars reduced midseason PRKN abundances from roots by 92-98% and final PRKN soil abundances by 81-93% relative to the untreated susceptible cultivar. Fluopyram reduced midseason PRKN root abundances by 65-74% and final PRKN soil abundances by 42-51% relative to untreated susceptible. Although PRKN reproduced on peanuts, no damage symptoms were observed, yield did not vary by treatment in 2022, and yield was significantly greater for fluopyram than either resistant cultivar in 2023. Impacts on total free-living nematode soil abundances were inconsistent. In summary, either fluopyram or resistant cultivars are effective tools for managing PRKN abundances in Virginia-type peanuts.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250010"},"PeriodicalIF":1.4,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12014208/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143997554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Draft Genome Assembly of Root Knot Nematode, <i>Meloidogyne fallax</i>.","authors":"Sarah Olivia Griffin, Valeria Orlando, Chris Conyers, Rebecca Lawson, Thomas Prior, Eleanor Jones, Edward Haynes, Evelyn L Jensen","doi":"10.2478/jofnem-2025-0016","DOIUrl":"https://doi.org/10.2478/jofnem-2025-0016","url":null,"abstract":"<p><p><i>Meloidosgyne fallax</i> (false Columbia root knot nematode) is an invasive crop pest recorded across Europe, Africa, North America, and Oceania. Here we present the draft genome assembly of <i>M. fallax</i> which was de novo assembled and scaffolded using <i>M. chitwoodi</i> (Columbia root knot nematode), a close relative of <i>M. fallax</i>.</p>","PeriodicalId":16475,"journal":{"name":"Journal of nematology","volume":"57 1","pages":"20250016"},"PeriodicalIF":1.4,"publicationDate":"2025-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12002905/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144009049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}