Pseudaphelenchus taedae n. sp., isolated from loblolly pine logs (Pinus taeda L.) from the USA and peat from Lithuania, is described and figured. It is characterised by the male 355 (305-401) μm and female 427 (318-520) μm body lengths and by the presence of three equal incisures in the lateral field. The slender stylet has small but conspicuous basal knobs. Valve is located at posterior part of metacorpus. The excretory pore is located at the same level as valve plates or anterior. Spicules are paired, thorn-like, separate, condylus broadly rounded, rostrum conical or triangular with a bluntly pointed tip, calomus smoothly tapering together with lamina, thin and strongly arcuate in middle then tapering towards bluntly pointed distal tip, cucullus absent. A narrow bursa surrounds three quarters of tail but is inconspicuous in most cases. The conical male tail is bluntly rounded but mostly with a short pointed or blunt mucron. The female tail is conical in various shapes, smoothly tapering, slightly ventrally bent or curved, with broadly rounded or pointed terminus. Detailed phylogenetic analysis based on the 18S and D2-D3 region of 28S sequences confirmed the status of this nematode as a new species.
{"title":"Pseudaphelenchus taedae n. sp. (Tylenchina: Aphelenchoididae) found in loblolly pine logs from the USA and peat from Lithuania","authors":"J. Gu, Lirong Zhao, Fei-yu Yan, Yiwu Fang, Xinxin Ma, Mutao Wu, Yong Bian","doi":"10.1163/15685411-bja10321","DOIUrl":"https://doi.org/10.1163/15685411-bja10321","url":null,"abstract":"\u0000Pseudaphelenchus taedae n. sp., isolated from loblolly pine logs (Pinus taeda L.) from the USA and peat from Lithuania, is described and figured. It is characterised by the male 355 (305-401) μm and female 427 (318-520) μm body lengths and by the presence of three equal incisures in the lateral field. The slender stylet has small but conspicuous basal knobs. Valve is located at posterior part of metacorpus. The excretory pore is located at the same level as valve plates or anterior. Spicules are paired, thorn-like, separate, condylus broadly rounded, rostrum conical or triangular with a bluntly pointed tip, calomus smoothly tapering together with lamina, thin and strongly arcuate in middle then tapering towards bluntly pointed distal tip, cucullus absent. A narrow bursa surrounds three quarters of tail but is inconspicuous in most cases. The conical male tail is bluntly rounded but mostly with a short pointed or blunt mucron. The female tail is conical in various shapes, smoothly tapering, slightly ventrally bent or curved, with broadly rounded or pointed terminus. Detailed phylogenetic analysis based on the 18S and D2-D3 region of 28S sequences confirmed the status of this nematode as a new species.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140674809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1163/15685411-bja10320
V. V. Yushin, L. Gliznutsa, N. Kanzaki, A. Ryss
Sperm development and structure in the wood-inhabiting fungal and plant-feeding nematode, Bursaphelenchus luxuriosae, were studied using transmission electron microscopy to evaluate interspecific similarities and differences of spermatozoa in nematodes. In general, spermatogenesis in B. luxuriosae fits the ‘rhabditid’ pattern supported by morphological and phylogenetic analysis of the order Rhabditida. Spermatocyte development includes formation of complexes of fibrous bodies (FBs) with membranous organelles (MOs), the complexes dissociate in the spermatids into separate components, and the immature sperm contain MOs but lack FBs, which transform into a dense matrix of sperm cytoplasm. The female spermatheca contains mature spermatozoa as bipolar cells subdivided into a pseudopod devoid of organelles and a main cell body containing a nucleus without a nuclear envelope, numerous mitochondria, and peripheral MOs as pouches opening to the exterior via pores. Data on B. luxuriosae are used for analysis of variable quantitative and morphological characteristics of spermatozoa in Aphelenchoidea. General size of spermatozoa and their MOs have little value for comparative analysis. The MO knobbles look uniform in immature spermatozoa of each aphelenchoidid species studied and may be considered as a taxonomically specific ultrastructural feature. The presence or absence of FBs in immature spermatozoa demonstrates the diagnostic value of the aphelenchoidid sperm structure at the species level. Analysis also shows close similarity of spermatozoa in Bursaphelenchus spp. and Caenorhabditis elegans, the model species with comprehensive data on sperm biology. This may be used to identify new ways for the control and suppression of harmful nematode species such as B. xylophilus.
利用透射电子显微镜研究了栖息于林木中的真菌线虫和食植物线虫茂盛线虫（Bursaphelenchus luxuriosae）的精子发育和结构，以评估线虫精子的种间异同。总体而言，茂盛线虫的精子发生符合形态学和系统发育分析所支持的 "横纹线虫 "模式。精母细胞的发育包括纤维体（FBs）与膜质细胞器（MOs）复合体的形成，复合体在精子中解离成单独的成分，未成熟的精子含有MOs，但缺乏FBs，FBs转变成精子胞质的致密基质。雌性精巢中的成熟精子为双极细胞，细分为无细胞器的伪足和包含无核包膜的细胞核、大量线粒体的主细胞体，外围的 MO 通过小孔向外部开放。关于 B. luxuriosae 的数据被用于分析 Aphelenchoidea 中精子的数量和形态特征。精子的一般大小及其 MO 对于比较分析没有什么价值。在所研究的每个类天牛属物种的未成熟精子中，MO旋结看起来都是一致的，可被视为分类学上的特异性超微结构特征。未成熟精子中存在或不存在FBs证明了天牛精子结构在物种水平上的诊断价值。分析还显示，在精子生物学数据全面的模式物种中，Bursaphelenchus spp.和Caenorhabditis elegans的精子非常相似。这可用于确定控制和抑制有害线虫（如嗜木线虫）的新方法。
{"title":"Sperm development and structure in Bursaphelenchus luxuriosae (Nematoda: Aphelenchoidea: Aphelenchoididae)","authors":"V. V. Yushin, L. Gliznutsa, N. Kanzaki, A. Ryss","doi":"10.1163/15685411-bja10320","DOIUrl":"https://doi.org/10.1163/15685411-bja10320","url":null,"abstract":"\u0000Sperm development and structure in the wood-inhabiting fungal and plant-feeding nematode, Bursaphelenchus luxuriosae, were studied using transmission electron microscopy to evaluate interspecific similarities and differences of spermatozoa in nematodes. In general, spermatogenesis in B. luxuriosae fits the ‘rhabditid’ pattern supported by morphological and phylogenetic analysis of the order Rhabditida. Spermatocyte development includes formation of complexes of fibrous bodies (FBs) with membranous organelles (MOs), the complexes dissociate in the spermatids into separate components, and the immature sperm contain MOs but lack FBs, which transform into a dense matrix of sperm cytoplasm. The female spermatheca contains mature spermatozoa as bipolar cells subdivided into a pseudopod devoid of organelles and a main cell body containing a nucleus without a nuclear envelope, numerous mitochondria, and peripheral MOs as pouches opening to the exterior via pores. Data on B. luxuriosae are used for analysis of variable quantitative and morphological characteristics of spermatozoa in Aphelenchoidea. General size of spermatozoa and their MOs have little value for comparative analysis. The MO knobbles look uniform in immature spermatozoa of each aphelenchoidid species studied and may be considered as a taxonomically specific ultrastructural feature. The presence or absence of FBs in immature spermatozoa demonstrates the diagnostic value of the aphelenchoidid sperm structure at the species level. Analysis also shows close similarity of spermatozoa in Bursaphelenchus spp. and Caenorhabditis elegans, the model species with comprehensive data on sperm biology. This may be used to identify new ways for the control and suppression of harmful nematode species such as B. xylophilus.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140725764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1163/15685411-bja10322
J. Gu, M. Munawar, Xinxin Ma, Yiwu Fang
The genus Ektaphelenchoides is a diverse group of nematodes; they are either inhabitants of trees or present in the rhizosphere of economical plants. Members of the genus have ecological relevance in terms of being associated with insects and predators of other nematodes. In the present study, a new Ektaphelenchoides species, E. factum n. sp., is described and illustrated. The new species was isolated from a log sample of Pinus taeda imported from the USA. It is characterised by the lateral field with three incisures, stylet distinctly tripartite. Females having a vulval flap, the anus and rectum indistinct, and the tail (posterior part of body) filiform. Males having arcuate and 21.5 (19.4-22.9) μm long spicules, the lamina of the spicule is smoothly curved to distal end, condylus well developed with a broadly rounded tip, rostrum triangular with finely rounded tip and cucullus absent, tail arcuate and conical with terminus bearing a sharply pointed mucron. The new species is different from other Ektaphelenchoides species in having a vulval flap. Molecular characterisation and phylogenetic studies also supported its unique status. In addition, a Chinese native population of E. pini, detected in Pinus koraiensis branches from Liaoning province, P.R. China, is described.
Ektaphelenchoides 属是一个种类繁多的线虫类群；它们或是树木的居民，或是存在于经济植物的根圈中。该属的成员与昆虫和其他线虫的天敌相关，因此具有生态学意义。在本研究中，描述并说明了一种新的 Ektaphelenchoides 物种--E. factum n. sp.。该新种是从美国进口的太田松原木样本中分离出来的。其特征是侧领域有三个切口，花柱明显呈三叉状。雌性有外阴瓣，肛门和直肠不明显，尾部（身体后部）呈丝状。雄性有弧曲的 21.5（19.4-22.9）微米长的小刺，小刺的薄片平滑地弯曲至远端，髁发达，顶端宽圆，喙三角形，顶端细圆，无鳞茎，尾弧曲，圆锥形，末端有尖锐的短尖头。该新种与其他 Ektaphelenchoides 种类不同，具有外阴瓣。分子特征和系统发育研究也支持其独特的地位。此外，还描述了在中国辽宁省的柯来松枝条中发现的 E. pini 的中国原生种群。
{"title":"Ektaphelenchoides factum n. sp. in Pinus taeda from the USA and E. pini in Pinus koraiensis from China","authors":"J. Gu, M. Munawar, Xinxin Ma, Yiwu Fang","doi":"10.1163/15685411-bja10322","DOIUrl":"https://doi.org/10.1163/15685411-bja10322","url":null,"abstract":"\u0000The genus Ektaphelenchoides is a diverse group of nematodes; they are either inhabitants of trees or present in the rhizosphere of economical plants. Members of the genus have ecological relevance in terms of being associated with insects and predators of other nematodes. In the present study, a new Ektaphelenchoides species, E. factum n. sp., is described and illustrated. The new species was isolated from a log sample of Pinus taeda imported from the USA. It is characterised by the lateral field with three incisures, stylet distinctly tripartite. Females having a vulval flap, the anus and rectum indistinct, and the tail (posterior part of body) filiform. Males having arcuate and 21.5 (19.4-22.9) μm long spicules, the lamina of the spicule is smoothly curved to distal end, condylus well developed with a broadly rounded tip, rostrum triangular with finely rounded tip and cucullus absent, tail arcuate and conical with terminus bearing a sharply pointed mucron. The new species is different from other Ektaphelenchoides species in having a vulval flap. Molecular characterisation and phylogenetic studies also supported its unique status. In addition, a Chinese native population of E. pini, detected in Pinus koraiensis branches from Liaoning province, P.R. China, is described.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140723100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1163/15685411-bja10317
John M. Webster
This Forum article traces the initiation and development of research into plant-parasitic and entomopathogenic nematodes in Canada going back 170 years. It highlights the major achievements and the scientists involved up to the present day.
{"title":"Arrival and survival of nematology in Canada","authors":"John M. Webster","doi":"10.1163/15685411-bja10317","DOIUrl":"https://doi.org/10.1163/15685411-bja10317","url":null,"abstract":"\u0000This Forum article traces the initiation and development of research into plant-parasitic and entomopathogenic nematodes in Canada going back 170 years. It highlights the major achievements and the scientists involved up to the present day.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140722817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-09DOI: 10.1163/15685411-bja10319
Ignacio Cid del Prado-Vera, Howard Ferris, S. Subbotin
In 2018-2022, during nematological surveys in several Mexican states, a new species, Xiphinema ficusi sp. n., two known species, X. basiri and X. luci, and four unidentified Xiphinema species, Xiphinema sp. A, sp. B, sp. C, and sp. D, were collected and characterised. Xiphinema ficusi sp. n. was found in a tropical forest in the La Mancha Ecological Reserve of the Ecology Institute of Jalapa, Veracruz state. The new species is characterised by a body length of 2.82-3.79 mm, slightly offset lip region, odontostyle 93-105 μm long, guiding ring at 51-96 μm from anterior end, an elongate conical tail 41-50 μm long with digitate terminus, didelphic-amphidelphic reproductive system, with both gonads equally developed without Z differentiation in females. Males have one pair of adanal and four ventromedial supplements. The seven Xiphinema species were molecularly characterised and the phylogenetic relationships of these species with other representatives of this genus were reconstructed using the D2-D3 expansion segments of 28S rRNA and COI gene sequences. Molecular analysis revealed the presence of a parasitic oomycete of the genus Lagenidium in X. ficusi sp. n. and endosymbiotic bacteria of the genus Candidatus Xiphinematobacter in X. luci and Xiphinema sp. D. belonging to the Xiphinema americanum group. It has been suggested that valleys surrounded by ridges of Sierra Madre Mountains in Mexico might be one of the world centres of diversity for the genus Xiphinema.
{"title":"Description of Xiphinema ficusi sp. n. (Nematoda: Longidoridae) and molecular characterisation of some Xiphinema species from Mexico","authors":"Ignacio Cid del Prado-Vera, Howard Ferris, S. Subbotin","doi":"10.1163/15685411-bja10319","DOIUrl":"https://doi.org/10.1163/15685411-bja10319","url":null,"abstract":"\u0000In 2018-2022, during nematological surveys in several Mexican states, a new species, Xiphinema ficusi sp. n., two known species, X. basiri and X. luci, and four unidentified Xiphinema species, Xiphinema sp. A, sp. B, sp. C, and sp. D, were collected and characterised. Xiphinema ficusi sp. n. was found in a tropical forest in the La Mancha Ecological Reserve of the Ecology Institute of Jalapa, Veracruz state. The new species is characterised by a body length of 2.82-3.79 mm, slightly offset lip region, odontostyle 93-105 μm long, guiding ring at 51-96 μm from anterior end, an elongate conical tail 41-50 μm long with digitate terminus, didelphic-amphidelphic reproductive system, with both gonads equally developed without Z differentiation in females. Males have one pair of adanal and four ventromedial supplements. The seven Xiphinema species were molecularly characterised and the phylogenetic relationships of these species with other representatives of this genus were reconstructed using the D2-D3 expansion segments of 28S rRNA and COI gene sequences. Molecular analysis revealed the presence of a parasitic oomycete of the genus Lagenidium in X. ficusi sp. n. and endosymbiotic bacteria of the genus Candidatus Xiphinematobacter in X. luci and Xiphinema sp. D. belonging to the Xiphinema americanum group. It has been suggested that valleys surrounded by ridges of Sierra Madre Mountains in Mexico might be one of the world centres of diversity for the genus Xiphinema.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140721925","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-28DOI: 10.1163/15685411-bja10318
Habtamu Kefelegn, Beira-Hailu Meressa, Wim M.L. Wesemael, M. G. Teklu, Sunheng Yon, M. Couvreur, A. Aseffa, W. Bert
Chickpea is one of the most important legume crops in Ethiopia; however, its production is far below the mean international chickpea production due to biotic and abiotic stressors. Plant-parasitic nematode infestation is extensive in chickpea-growing areas worldwide. The distribution and population density of plant-parasitic nematodes in chickpea were determined during the September-December 2021 growing season. Ten plant-parasitic nematode taxa were identified from 27 localities across ten districts in the main chickpea-growing areas in Ethiopia. Pratylenchus had the highest prominence values, followed by Rotylenchulus and Meloidogyne spp. Helicotylenchus, Hoplolaimus, Scutellonema and Quinisulcius were more prevalent than Criconemoides and Ditylenchus. Sequences of different molecular markers, including D2-D3 of 28S rDNA, ITS of rDNA, and COI and Nad5 of mtDNA, revealed the presence of Meloidogyne javanica, Rotylenchulus parvus, Scutellonema clathricaudatum and Helicotylenchus caudatus. Helicotylenchus caudatus and R. parvus are the first reports from Ethiopia and chickpea, while S. clathricaudatum is the first report for chickpea. This study provides essential baseline information of nematode pest occurrence on chickpea in Ethiopia. This information will raise awareness among growers, agricultural officers, and extension advisors, enabling them to develop effective nematode management strategies for the chickpea production system in Ethiopia.
{"title":"Diversity of plant-parasitic nematodes associated with chickpea (Cicer arietinum L.) in the main growing areas of Ethiopia","authors":"Habtamu Kefelegn, Beira-Hailu Meressa, Wim M.L. Wesemael, M. G. Teklu, Sunheng Yon, M. Couvreur, A. Aseffa, W. Bert","doi":"10.1163/15685411-bja10318","DOIUrl":"https://doi.org/10.1163/15685411-bja10318","url":null,"abstract":"\u0000Chickpea is one of the most important legume crops in Ethiopia; however, its production is far below the mean international chickpea production due to biotic and abiotic stressors. Plant-parasitic nematode infestation is extensive in chickpea-growing areas worldwide. The distribution and population density of plant-parasitic nematodes in chickpea were determined during the September-December 2021 growing season. Ten plant-parasitic nematode taxa were identified from 27 localities across ten districts in the main chickpea-growing areas in Ethiopia. Pratylenchus had the highest prominence values, followed by Rotylenchulus and Meloidogyne spp. Helicotylenchus, Hoplolaimus, Scutellonema and Quinisulcius were more prevalent than Criconemoides and Ditylenchus. Sequences of different molecular markers, including D2-D3 of 28S rDNA, ITS of rDNA, and COI and Nad5 of mtDNA, revealed the presence of Meloidogyne javanica, Rotylenchulus parvus, Scutellonema clathricaudatum and Helicotylenchus caudatus. Helicotylenchus caudatus and R. parvus are the first reports from Ethiopia and chickpea, while S. clathricaudatum is the first report for chickpea. This study provides essential baseline information of nematode pest occurrence on chickpea in Ethiopia. This information will raise awareness among growers, agricultural officers, and extension advisors, enabling them to develop effective nematode management strategies for the chickpea production system in Ethiopia.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140370321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.1163/15685411-bja10315
Valeria Orlando, David Roberts, Simon G. Edwards, Thomas Prior, Roy Neilson, M. Back
Pratylenchus crenatus, P. neglectus, P. penetrans and P. thornei are globally the most commonly occurring species of root-lesion nematodes (RLN). Correct identification and quantification of these nematodes is important for strategic management interventions such as rotation choice and nematicide use. A real-time quantitative PCR can provide a fast and reliable alternative to morphological identification, which requires significant taxonomic experience. A TaqMan hydrolysis probe method based on the 28S rDNA D2-D3 expansion region was developed and validated for the identification and quantification of these four root-lesion nematode species. Standard curves for each target RLN species were generated by plotting known gene copy number, obtained by a ten-fold serial dilution of purified plasmids, with corresponding Ct values. Each standard curve had a strong linear correlation () between Ct value and gene copy number. There was consistent amplification of samples with target species from different geographic locations within the UK, whereas a lack of amplification was noted for selected non-target species: P. coffeae, P. pseudocoffeae, P. vulnus, P. fallax, Globodera rostochiensis, Meloidogyne hapla, Trichodorus primitivus and Bitylenchus hispaniensis. Specificity and sensitivity of the methods were confirmed by three experiments that explored different life stages, increasing the number of target species, and had mixed Pratylenchus samples. Finally, estimates obtained by qPCR methods were compared with counting carried out by microscopy showing a good correlation (). The TaqMan real-time PCR developed in this study provides a specific, fast and accurate quantification of P. crenatus, P. neglectus, P. penetrans and P. thornei.
{"title":"Development and validation of four TaqMan real-time PCR diagnostics for the identification and quantification of Pratylenchus crenatus, Pratylenchus neglectus, Pratylenchus penetrans and Pratylenchus thornei","authors":"Valeria Orlando, David Roberts, Simon G. Edwards, Thomas Prior, Roy Neilson, M. Back","doi":"10.1163/15685411-bja10315","DOIUrl":"https://doi.org/10.1163/15685411-bja10315","url":null,"abstract":"\u0000Pratylenchus crenatus, P. neglectus, P. penetrans and P. thornei are globally the most commonly occurring species of root-lesion nematodes (RLN). Correct identification and quantification of these nematodes is important for strategic management interventions such as rotation choice and nematicide use. A real-time quantitative PCR can provide a fast and reliable alternative to morphological identification, which requires significant taxonomic experience. A TaqMan hydrolysis probe method based on the 28S rDNA D2-D3 expansion region was developed and validated for the identification and quantification of these four root-lesion nematode species. Standard curves for each target RLN species were generated by plotting known gene copy number, obtained by a ten-fold serial dilution of purified plasmids, with corresponding Ct values. Each standard curve had a strong linear correlation () between Ct value and gene copy number. There was consistent amplification of samples with target species from different geographic locations within the UK, whereas a lack of amplification was noted for selected non-target species: P. coffeae, P. pseudocoffeae, P. vulnus, P. fallax, Globodera rostochiensis, Meloidogyne hapla, Trichodorus primitivus and Bitylenchus hispaniensis. Specificity and sensitivity of the methods were confirmed by three experiments that explored different life stages, increasing the number of target species, and had mixed Pratylenchus samples. Finally, estimates obtained by qPCR methods were compared with counting carried out by microscopy showing a good correlation (). The TaqMan real-time PCR developed in this study provides a specific, fast and accurate quantification of P. crenatus, P. neglectus, P. penetrans and P. thornei.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140408714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.1163/15685411-bja10314
Joseph O. Maosa, P. R. Singh, Abdul-Ganew Asumaila, M. Couvreur, W. Bert
Paratylenchus cacao n. sp., a pin nematode associated with cocoa (Theobroma cacao L.) from Ghana, is described herein based on morphology, morphometrics and phylogenetic relationships with other species. Morphologically, P. cacao n. sp. is characterised by a female body length of 174-265 μm, body assuming a ‘C’ or ‘J’ shape after heat relaxation, a flat head, slightly set off lip region, a truncated anterior end, a rigid stylet of 24-31 μm, four lateral lines, vulval region with distinct vulval flaps, and a finely rounded tail with a mucron-like terminus. The findings of the phylogenetic analyses utilising the D2-D3 expansion segments of 28S, ITS of rDNA, and COI of mitochondrial DNA sequences indicate that P. cacao n. sp. is a species closely related to P. leptos. Additionally, based on butterhead lettuce and leek populations from Belgium, the first description of a male, SEM pictures and COI sequences of P. enigmaticus are presented. Both studies exemplify how even potentially important plant-parasitic nematode species can remain unnoticed for a long time. This suggests the need to conduct more nematode diversity studies and underscores the significance of correct nematode identification through the utilisation of tools such as integrative taxonomy.
本文根据形态学、形态计量学以及与其他物种的系统发育关系，描述了加纳可可（Theobroma cacao L.）上的一种蛲虫--Paratylenchus cacao n. sp.。从形态上看，P. cacao n. sp.的特征是：雌虫体长 174-265 μm，热松弛后身体呈 "C "形或 "J "形，头部扁平，唇区稍偏离，前端截断，硬质花柱长 24-31 μm，有四条侧线，外阴区有明显的外阴瓣，尾部细圆，末端呈短尖头状。利用 28S 的 D2-D3 扩增片段、rDNA 的 ITS 和线粒体 DNA 的 COI 序列进行的系统进化分析结果表明，可可蛙是与瘦蛙亲缘关系密切的物种。此外，基于比利时的莴苣头和韭菜种群，首次描述了谜样莴苣头的雄性、扫描电镜图片和 COI 序列。这两项研究说明，即使是潜在的重要植物寄生线虫物种，也可能长期不被注意。这表明有必要开展更多的线虫多样性研究，并强调了利用综合分类法等工具正确识别线虫的重要性。
{"title":"Characterisation of Paratylenchus cacao n. sp. from Ghana, and P. enigmaticus (Nematoda: Paratylenchinae) from Belgium","authors":"Joseph O. Maosa, P. R. Singh, Abdul-Ganew Asumaila, M. Couvreur, W. Bert","doi":"10.1163/15685411-bja10314","DOIUrl":"https://doi.org/10.1163/15685411-bja10314","url":null,"abstract":"\u0000Paratylenchus cacao n. sp., a pin nematode associated with cocoa (Theobroma cacao L.) from Ghana, is described herein based on morphology, morphometrics and phylogenetic relationships with other species. Morphologically, P. cacao n. sp. is characterised by a female body length of 174-265 μm, body assuming a ‘C’ or ‘J’ shape after heat relaxation, a flat head, slightly set off lip region, a truncated anterior end, a rigid stylet of 24-31 μm, four lateral lines, vulval region with distinct vulval flaps, and a finely rounded tail with a mucron-like terminus. The findings of the phylogenetic analyses utilising the D2-D3 expansion segments of 28S, ITS of rDNA, and COI of mitochondrial DNA sequences indicate that P. cacao n. sp. is a species closely related to P. leptos. Additionally, based on butterhead lettuce and leek populations from Belgium, the first description of a male, SEM pictures and COI sequences of P. enigmaticus are presented. Both studies exemplify how even potentially important plant-parasitic nematode species can remain unnoticed for a long time. This suggests the need to conduct more nematode diversity studies and underscores the significance of correct nematode identification through the utilisation of tools such as integrative taxonomy.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140413821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-29DOI: 10.1163/15685411-bja10316
Zengqi Zhao, J. Gu, Tanya Greenwood, Brent Rogan, Wellcome Ho, Robert Taylor
Bursaphelenchus zealandicus sp. n. was extracted from a dead pine tree (Pinus radiata) in Kinleith Forest, Taupo, New Zealand (NZ). This is the fourth Bursaphelenchus species from NZ. Bursaphelenchus zealandicus sp. n. is characterised by a body length of 562 (466-730) μm and 580 (470-706) μm of males and females, respectively, slim body (a = 34.7 and 33.1, respectively), stylet 11.4 (9.7-13.0) μm long for males and 10.7 (9.4-12.1) μm for females, lateral field with three lines, the mean value of the vulva position 71.8%, lacking a vulval flap in lateral view, length of the post-uterine branch ca 41.6% of the vulva-anus distance, the female tail long and conical (c = 19.3), tapering to a finely rounded terminus, ventrally curved like a hook, the male with spicules 12.3 μm long in chord, having an obvious developed rostrum and condylus, the rostrum sharply pointed, the male tail terminus with a distinct bursa seen in dorso-ventral position, a single pre-anal papilla, two pairs of ventro-sublateral papillae (one pair pre-anal (P2), one pair post-anal (P3) just in front of the bursa) and one pair of ventral mid-line glandular papillae (P4) present. The combination of three lateral lines and the position of caudal papillae reveal a relationship of the new species to other three-lined groups (hofmanni-group, eggersi-group, eremus-group, leoni-group); however, the shape of the spicules is different and unique among the known species of Bursaphelenchus. Its taxonomic status has been confirmed by analyses of the near full length small subunit (SSU), the internal transcribed spacer region (ITS1 and 2), D2-D3 expansion segments of the large subunit (LSU) of the ribosomal rDNA and the mitochondrial cytochrome c oxidase subunit I (COI) gene.
{"title":"Bursaphelenchus zealandicus sp. n. (Tylenchina: Aphelenchoididae), a new species of the hofmanni-group from Pinus radiata in New Zealand","authors":"Zengqi Zhao, J. Gu, Tanya Greenwood, Brent Rogan, Wellcome Ho, Robert Taylor","doi":"10.1163/15685411-bja10316","DOIUrl":"https://doi.org/10.1163/15685411-bja10316","url":null,"abstract":"\u0000Bursaphelenchus zealandicus sp. n. was extracted from a dead pine tree (Pinus radiata) in Kinleith Forest, Taupo, New Zealand (NZ). This is the fourth Bursaphelenchus species from NZ. Bursaphelenchus zealandicus sp. n. is characterised by a body length of 562 (466-730) μm and 580 (470-706) μm of males and females, respectively, slim body (a = 34.7 and 33.1, respectively), stylet 11.4 (9.7-13.0) μm long for males and 10.7 (9.4-12.1) μm for females, lateral field with three lines, the mean value of the vulva position 71.8%, lacking a vulval flap in lateral view, length of the post-uterine branch ca 41.6% of the vulva-anus distance, the female tail long and conical (c = 19.3), tapering to a finely rounded terminus, ventrally curved like a hook, the male with spicules 12.3 μm long in chord, having an obvious developed rostrum and condylus, the rostrum sharply pointed, the male tail terminus with a distinct bursa seen in dorso-ventral position, a single pre-anal papilla, two pairs of ventro-sublateral papillae (one pair pre-anal (P2), one pair post-anal (P3) just in front of the bursa) and one pair of ventral mid-line glandular papillae (P4) present. The combination of three lateral lines and the position of caudal papillae reveal a relationship of the new species to other three-lined groups (hofmanni-group, eggersi-group, eremus-group, leoni-group); however, the shape of the spicules is different and unique among the known species of Bursaphelenchus. Its taxonomic status has been confirmed by analyses of the near full length small subunit (SSU), the internal transcribed spacer region (ITS1 and 2), D2-D3 expansion segments of the large subunit (LSU) of the ribosomal rDNA and the mitochondrial cytochrome c oxidase subunit I (COI) gene.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140410994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-02-28DOI: 10.1163/15685411-bja10313
F. Fekrat, R. Ghaderi, E. Pourjam, P. Castillo, M. Pedram
A population of Xiphinema artemisiae was recovered from Iran, representing the first report after its original description from a meadow pasture in northern Caucasus, Russia. The Iranian population was recovered from the rhizosphere of grasses in the Damavand region, Tehran province. The females of the recovered populations are characterised by a lip region separated from the rest of body by a depression, a 5.1-5.6 mm long body, a 129-138 μm long odontostyle, 76-85 μm long odontophore, a uterus having a pseudo-Z-organ and crystalloid bodies observed in some specimens, and a short, rounded, dorsally more convex tail with a subcentral mucron, four juvenile developmental stages (the first stage was not recovered) and functional males. The Iranian population is morphologically and morphometrically similar to the type population and minor morphological differences can be attributed to geographical interpopulation differences. Molecular phylogenetic relationships of the Iranian population of X. artemisiae with other species were reconstructed using sequences of three genomic ribosomal markers, viz. small, large subunit D2-D3 and internal transcribed spacer (SSU, LSU D2-D3 and ITS) rDNA.
{"title":"Redescription of Xiphinema artemisiae Chizhov, Tiev & Turkina, 1986 (Dorylaimida: Longidoridae): new occurrence in Iran","authors":"F. Fekrat, R. Ghaderi, E. Pourjam, P. Castillo, M. Pedram","doi":"10.1163/15685411-bja10313","DOIUrl":"https://doi.org/10.1163/15685411-bja10313","url":null,"abstract":"\u0000A population of Xiphinema artemisiae was recovered from Iran, representing the first report after its original description from a meadow pasture in northern Caucasus, Russia. The Iranian population was recovered from the rhizosphere of grasses in the Damavand region, Tehran province. The females of the recovered populations are characterised by a lip region separated from the rest of body by a depression, a 5.1-5.6 mm long body, a 129-138 μm long odontostyle, 76-85 μm long odontophore, a uterus having a pseudo-Z-organ and crystalloid bodies observed in some specimens, and a short, rounded, dorsally more convex tail with a subcentral mucron, four juvenile developmental stages (the first stage was not recovered) and functional males. The Iranian population is morphologically and morphometrically similar to the type population and minor morphological differences can be attributed to geographical interpopulation differences. Molecular phylogenetic relationships of the Iranian population of X. artemisiae with other species were reconstructed using sequences of three genomic ribosomal markers, viz. small, large subunit D2-D3 and internal transcribed spacer (SSU, LSU D2-D3 and ITS) rDNA.","PeriodicalId":18928,"journal":{"name":"Nematology","volume":null,"pages":null},"PeriodicalIF":1.2,"publicationDate":"2024-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140422220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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