• Journal of Species Research
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• v.8 no.3
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• pp.259-267
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• 2019

Five free-living nematode species belonging to the order of Rhabditida are described for the first time in Korea. Two unrecorded species of Rhabditidae, Cruznema tripartitum (Linston, 1906) Zullini, 1982, and Poikilolaimus oxycerca de Man, 1895, and one species of Peloderidae, Pelodera strongyloides Schneider, 1860, were collected in Korea. C. tripartitum has nine pairs of genital papillae arranged in 2+2+1+4 differently from similar species of C. scarabaeum which has ten genital papillae arranged in 2+1+4+3. Poikilolaimus oxycerca has shorter tail (shorter than anal body diameter) compared to similar species of P. regenfussi which has longer tail(longer than anal body diameter). Pelodera strongyloides has shorter tail(1-1.5 times anal body diameters long) than P. punctata (4 anal body diameters long). Two unrecorded species of Panagrolaimidae, Panagrolaimus apicatus Schuurmans Stekhoven & Teunissen, 1938 and Panagrolaimus rigidus (Schneider, 1866) Thorne, 1937 were collected in Korea. P. apicatus has rounded and lower lip compared to similar species, P. margaretae Massey, 1964 which has finely pointed lip. P. rigidus has slender tail and lips rounded and flat barely separated when compared to similar species, P. subelongatus(Cobb, 1914) Thorne, 1937 which has plumper tail and lips are well separated.

• The Plant Pathology Journal
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• v.25 no.3
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• pp.247-255
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• 2009

Root-knot nematode species, such as Meloidogyne hapla, M. incognita, M. arenaria, and M. javanica are the most economically notorious nematode pests, causing serious damage to a variety of crops throughout the world. In this study, DNA sequence analyses were performed on the D3 expansion segment of the 28S gene in the ribosomal DNA in an effort to characterize genetic variations in the three Meloidogyne species obtained from Korea and four species from the United States. Further, PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism), SCAR (Sequence Characterized Amplified Region) PCR and RAPD (Randomly Amplified Polymorphic DNA) were also utilized to develop methods for the accurate and rapid species identification of the root-knot nematode species. In the sequence analysis of the D3 expansion segment, only a few nucleotide sequence variations were detected among M. incognita, M. arenaria, and M, javanica, but not M. hapla. As a result of our haplotype analysis, haplotype 5 was shown to be common in M. arenaria, M. incognita, M. javanica, but not in the facultatively parthenogenetic species, M. hapla. PCR-RFLP analysis involving the amplification of the mitochondrial COII and large ribosomal RNA (lrRNA) regions yielded one distinct amplicon for M. hapla at 500 bp, thereby enabling us to distinguish M. hapla from M. incognita, M. arenaria, and M. javanica reproduced via obligate mitotic parthenogenesis. SCAR markers were used to successfully identify the four tested root-knot nematode species. Furthermore, newly attempted RAPD primers for some available root-knot nematodes also provided some species-specific amplification patterns that could also be used to distinguish among root-knot nematode species for quarantine purposes.

• Korean journal of applied entomology
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• v.21 no.3 s.52
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• pp.146-152
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• 1982

Survey on potato parasitic nematodes has been undertaken in order to find distribution of the nemic fauna. 41 soil samples were taken from potato fields in Gyeongbug, Gyeongnam and Gangweon provinces. Twenty four species belonging to 16 different genera were identified. Potato cyst nematode, Globodera rostochiensis was not found in the areas. Potato-rot nematode, Ditylenchus destructor and stem nematode, Ditylenchus dipsaci were found from several potato fields and population density high and showed damage to the crops. Root-lesion nematode, Pratylenchus minyus, Pratylenchus penetrans, Pratytenchus thornei and Pratylenchus vulnus were found and their population of these four species were high depending on the fields. Root-knot nematode, Meloidogyne hapla and Meloidogyne incognita were found. M. hapla was found only in Gangweon province and the population density was high. M. incognita was found at Milyang in Gyeongnam province. Spiral nematode, Heticotylenchus digonichus, Helicotylenchus dihystera, Helicotylenchus pseudorobustus, Rotylenchus orientalis and Rotylenchus pini were found. Aphelenchoides saprophilus, Criconemoides informis, Ditylenchus destructor, D. dipsaci, Helicotylenchus digonichus, H. dihystera, Hemicriconemoides intermedius, Meloidogyne hapla, Psilenchus hilarulus, Pratylenchus minyus, and Xiphinema americanum were first found from potato fields in Korea.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.3 no.4
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• pp.221-226
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• 2022

A filarial nematode was found in a blood sample of an Anas falcata individual collected in South Korea in 2018. Phylogenetic analysis based on partial cytochrome C oxidase subunit I (COI) sequences placed the nematode as a novel genus of the family Onchocercidae and as closely related to Mansonella species, Chandlerella quiscali, and filarial nematodes recently reported in avian species. However, different phylogenetic relationship was observed in the NADH dehydrogenase subunit 5 and 12S rRNA-based phylogenetic trees, which might indicate the filarial nematode found in this study was not defined to belong to the known specific genera of the family Onchocercidae. The screening of 105 additional avian blood samples retrieved only one 12S rRNA-targeting polymerase chain reaction (PCR)-positive sample, which indicates that filarial nematode infection is rare in wild birds or that it occurs below the detection limit of PCR in blood samples. Nevertheless, considering the recent findings about ancient interactions between birds and human pathogenic filarial nematodes and their pathogenic potential in several avian species, additional exploration of novel filarial nematodes in wild birds remains necessary.

• Korean journal of applied entomology
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• v.29 no.1
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• pp.14-19
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• 1990

Nematodes and insects associated with dead trees were surveyed on the 238 dead trees belonging to 19 tree species in Pusan, Gyeongnam, Gyeongbuk, Chunnam, and Chonbuk provinces from April to September of 1989. Pine wood nematode, Bursaphelenchus xylophilus was found only in Pusan but B. mucronatus was collected at Chinju and Chinhae. The 13 nematode species in 9 genera were identified. Out of them, Diplogasteroides dimidius, Rhabdontolaimus adephagus, R. janae, Mikoletzkya diluta, M. ruminis, M. langcaudaa, Parasitorhabditis hylurgi, Panagrolaimus concolor, Panagrodontus dentatus, Prothalonema intermedium, and marcrolaimus canadensis were recorded for the first time in Korea. Insects collected from dead trees were 5 orders, 9 families, 25 genera, and 27 species. of them, the Coleoptera were the most collected insects by the 3 families, 19 genera and 22 species. The Scolytidae were 12 species in 10 genera. Hypothenemus eruditus was firstly collected from Campylotropis macrocarpa, Lespedeza maximowizi, Forsythia ovata, Meliosma oldhami, Securinega suffruticosa, Broussonetia kazinoki, and Cornus walteri. The maximum number of pine wood nematode was separated from the abdomen of Monchamus alternatus, the pine woodnematode vector. The maximum number of nematodes per an adult of M. alternatus was 127,535, minimum 2,616, and average 42,817.

• Animal Systematics, Evolution and Diversity
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• v.38 no.4
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• pp.205-213
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• 2022

A new free-living marine nematode, Chaetonema longicorpus sp. nov., was discovered in a subtidal benthic habitat around the Uljin nuclear power plant in the East Sea. Chaetonema longicorpus sp. nov. differs from other Chaetonema species in its very long body length, relatively long cephalic setae, long and narrow buccal cavity, bottle-shaped amphideal fovea, short spicules, only one pre-cloacal seta instead of a pre-cloacal supplement, and conspicuous ventral swelling at the middle of the tail. Herein, we provide a taxonomic description and illustrations of this new species using differential interference contrast microscopy. Furthermore, an illustrated pictorial key to all valid species, including the new species and comparative tables on the biogeographical and morphological characteristics of the genus Chaetonema, are provided.

• Research in Plant Disease
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• v.18 no.4
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• pp.381-386
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• 2012

Nematode fauna in Dokdo island was investigated for two years between 2008 and 2009. Population density and biomass were $239,500m^2$ (26,000-836,000) and $103.9mg/m^2$ (3.0-388.6), respectively. Total of 31 species of nematodes were identified : Acrobeloides is the most important genus with prominence value (PV) of 117.8, followed by Rhabditidae (PV = 81.9), Prismatolaimus (PV = 39.0), and Aphelenchoides (PV = 31.4). Among feeding group, bacteriovorus nematode composed 77% of density and 62% of biomass followed by plant-parasitic and fungivorus nematodes. A species of Pratylenchus having distinctive tail terminus is under study as a new species. Biological indices, Shannon and Wiener index (2.46), Simpson's diversity index (0.86), Species evenness (0.73), Species richness (1.30) indicate that nematode fauna in Dokdo island is diverse and unique. This study may give a general idea of nematode fauna at the Dokdo island.

• Research in Plant Disease
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• v.25 no.3
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• pp.149-155
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• 2019

Nematode-trapping fungi develop trap and consume nematodes are an important part of the subsoil ecosystem and they share a special predator-prey relationship. Four nematode-trapping species, there with adhesive network, Arthrobotrys oligospora, A. sinensis, A. thaumasia and one with constricting ring, Drechslerella brochopaga were collected from soils in Korea and tested their predacity against 12 different nematode species. They were three feeding groups, plant-parasitic (Meloidogyne incognita and Pratylenchus penetrans), fungivorous (Aphelenchus avenae), bacteriovorous (Betlerius sp. and Diplogasteritus sp. in diplogasterid, Panagrolaimus labiatus, P. multidentatus in panagrolaimid, Mesorhabditis irregularis, Pelodera strongyloides and Rhabditis sp., in rhabditid, and Acrobeloides sp. in cephalobid). Results showed that nematode-trapping fungi successfully captured most of nematodes in Petri dish in the group of plant-parasitic nematodes and rhabditids, moderately and variably in other nematodes in 15 days. But it didn't captured A. avenae and Acrobeloides sp. both belongs to c-p group 2. Numbers of Acrobeloides sp. and A. avenae even increased during the test period. The results of this study indicated that nematode-trapping fungi may have specificity among nematode species.

• Korean Journal of Organic Agriculture
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• v.27 no.4
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• pp.501-512
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• 2019

To survey the incidence of plant-parasitic nematodes, 187 soil samples from leguminous plant fields in Chungnam province, Korea were assessed from June to August 2018. As the result, four nematode genera - the cyst nematode (Heterodera spp.), root-knot nematode (Meloidogyne spp.), root-lesion nematode (Pratylenchus spp.), spiral nematode (Helicotylenchus spp.) - were detected. Among them, the incidence of cyst nematode was the highest in Taean (73%) and lowest in Hongseong (10%). The cyst nematode was detected from the adzuki and kidney bean fields as well as soybean fields. The incidence of cyst nematode in upland fields was higher than in paddy fields. In addition, the extracted cyst nematodes consisted of two species, which was identified as Heterodera glycines and H. sojae. The incidence of H. glycines (22%) was higher than H. sojae (10%), and a few of the fields (5%) was mixed with two cyst nematodes. This result suggested that we should consider that the cyst nematode is the major plantparasitic nematode when controlling the nematodes in soybean fields in Chungnam province.

• Korean Journal of Environmental Biology
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• v.39 no.4
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• pp.463-470
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• 2021

Admirandus multicavus Belogurov and Belogurova, 1979, a new record of free-living marine nematode species belonging to family Oncholaimidae is reported based on the specimens collected from the intertidal sediments of Korea. Admirandus multicavus is characterized by the following unique characteristics: cephalic setae (1-2 ㎛ long), spicules (71-126 ㎛ long) and gubernaculum (15-31 ㎛ long), midventral preanal supplementary organ, three glandular duct openings of the Demanian system, and stoma length measuring twice the width. A comparative analysis of the biogeographical and ecological characteristics of Admirandus species is presented. DIC (Differential interference contrast) photomicrographs of the species are also provided herein. This report represents the first taxonomic analysis of the genus Admirandus Belogurov and Belogurova, 1979 discovered from the Korean seawaters.