• Korean Journal of Agricultural Science
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• v.40 no.2
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• pp.101-106
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• 2013

To know how much damages occurred by nematodes in plastic vinyl house field, soil samples were collected from strawberry cultivation areas at Buyeo and Nonsan in Chungnam and Jinju in Kyeongnam, melon cultivation area at Gocksung in Junnam and cucumber field at Gongju in Chungnam. And then, nematode samples were separated from each soil sample, and identified the kind of plant-parasitic nematodes. Plant-parasitic nematodes were separated from 52 soil samples. Among samples, Meloidogyne spp., Pratylenchus spp. and Helicotylenchus spp. were isolated from 45 (86.5%%) and 33 (63.5%) and 47 collected soil samples (90.4%), respectively. As a result of identification of plant-parasitic nematodes from regional collected soil samples, distribution of Helicotylenchus spp. was higher than any other plant-parasitic nematode. And the population of Meloidogyne spp. and Pratylenchu spp. were also higher, and a occurrence ratio of Meloidogyne spp. is higher than Pratylenchu spp. except the cucumber growing area at Gongju.

• Korean journal of applied entomology
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• v.52 no.4
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• pp.327-333
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• 2013

Plant parasitic nematodes were isolated from 274 soil samples collected from soybean fields in Korea. Nematode importance rating in soybean is proposed based on this study and by reviewing other reports. Soybean cyst nematode, Heterodera glycines is the most important nematode species and rated as $1^{st}$ because it detected from 38%(range 25-51%) of soil samples with high density except Jeju province. Root-knot nematode, Meloidogyne spp. is rated $2^{nd}$ and is more widely distributed in southern provinces, Gyeongnam, Jeonnam, and Jeju province (detection rate ranged 16-44%). Pratylenchus is rated $3^{rd}$ and is more frequently detected from northern provinces such as Gyeonggi and Gangwon (detection rate ranged 10-13%). Helicotylenchus is rated $4^{th}$ and is particularly important in Jeju province (detection rate is 62% and numbers averaged 571 nematodes/$300cm^3$ soil), which is the main production area for sprouting soybean in Korea. Tylenchorhynchus, Paratylenchus, Criconema, Criconemoide, Mesocriconema, Ogma, Xiphinema, Paratrichodorus, and Trichodorus occur in low frequency and density, thus they are rated to $5^{th}$. We propose to delete following nematode genus from the list of soybean parasitic nematode in Korea because their parasitism on soybean is unconfirmed or negligible; Tylenchus, Aphelenchus, Aphelenchoides, Ditylenchus, Hirschmanniella immamuri, Basiria graminophila, Psilenchus, and Pseudhalenchus. Therefore, we revised 30 species in 16 genera as soybean parasitic nematodes in Korea. Importance rating is $1^{st}$ Heterodera glycines, $2^{nd}$ Meloidogyne spp., $3^{rd}$ Pratylenchus spp. and $4^{th}$ Helicotylenchus spp. especially in Jeju province.

• Research in Plant Disease
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• v.29 no.1
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• pp.45-51
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• 2023

The study was conducted to investigate the infestation and distribution of plant-parasitic nematodes on kiwi orchards in Korea. Plant parasitic nematodes genus and densities were investigated at a total of 102 sites in Jeollanam-do, Gyeongsangnam-do, and Jeju-do, which are the main production areas of domestic kiwi orchards. Plant parasitic nematodes detected were of 9 genera, including root-knot nematodes (Meloidogyne spp.), spiral nematodes (Helicotylenchus spp.), and needle nematodes (Paratylenchus spp.), and 56% of the 102 plantations were infected with root-knot nematodes. Root-knot nematodes were found to be the most important plant parasitic nematode in domestic kiwi orchards. The average density of root-knot nematodes is 97 per 300 cm³ soil, and there is concern about the kiwi yield reduction. As a result of identifying the root-knot nematode species: M. arenaria, M. hapla, M. incognita, and M. javanica. Among them, M. arenaria is the most dominant. As the plant parasitic nematode infection route in fruit trees is often spread through the transplantation of infected seedlings, attention should be paid to the production of nematode-free plants during the production and supply of kiwifruit plants.

• 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.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.306-310
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• 2012

Populations of plant-parasitic nematodes were evaluated in soil and root samples from areas planted with passion fruit, or covered with adjacent native cerrado vegetation, in five different cropping regions of the Brazilian Federal District. From July 2007 to January 2008, twenty samples had been collected in five Rural Centers (N$\acute{u}$cleo Rural-NR) planted with passion fruit. In five sites, samples were also collected in native cerrado vegetation. Specimens of nine genera of plant-parasitic nematodes (Meloidogyne, Helicotylenchus, Rotylenchulus, Scutellonema, Pratylenchus, Paratylenchus, Hemicycliophora, Xiphinema and Criconemoides) were found in the present survey. Important nematode pathogens, such as Rotylenchulus reniformis and Meloidogyne spp. were observed in the passion fruit plantations throughout five major producing regions of the Brazilian Federal District.

• Research in Plant Disease
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• v.22 no.4
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• pp.243-248
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• 2016

As preventive measures for bonsai exports, nematodes were isolated from 55 bonsai samples of five coniferous species (Chamaecyparis pisifera, Juniperus chinensis, Pinus densiflora, Pinus thunbergii, and Taxus cuspidate) from all 15 bonsai gardens in Korea. Nematodes belonging to 21 genera in 7 orders were isolated from the 55 bonsai samples. Among plant-parasitic nematodes, Tylenchus spp. was the most frequently isolated (14.9%), followed by Ditylenchus spp. (10.5%), Aphelenchoides spp. (9.5%), Aphelenchus sp. (5.5%), Criconemoides sp. (4.0%), Helicotylenchus sp. (0.7%), Hemicycliophora sp. (0.7%), Mesocriconema sp. (0.7%), Tylenchorhynchus sp. (0.7%), and Paratylenchus sp. (0.4%). Among nonparasitic nematodes, Cephalobina was the most frequently isolated nematodes (26.5%), followed by Rhabditida (19.3%), Dorylaimida (17.8%), Pangrolaimida (14.5%), Plectida (6.5%), Tryphylida (6.2%), Mononchida (3.3%), Alaimida (2.9%), Monhysterida (2.5%), and Triplonchida (0.4%). Based on these results, we conclude that there is no problematic plant-parasitic nematode in bonsai gardens of Korea.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.215-225
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• 2013

To assess the efficacy of nematicides for the control of plant-parasitic nematodes in fruit and vegetables fields, soil samples were collected from a cucumber field at Gongju; from strawberry fields at Buyeo, Nonsan, and Jinju; and from a melon field at Gocksung in Jeonnam Province, Korea. Plant-parasitic nematodes were separated from each soil sample and identified. The susceptibilities of the nematodes to abamectin 1.68% SC, cadusafos 3% GR, dazomet 98% GR, fosthiazate 30% SL and BA12011 SL were examined under laboratory and field conditions. The average population density of plant-parasitic nematodes was generally reduced after the treatment with nematicides; however, there was increase in the population of Pratylenchus spp. in soil after treatment with fosthiazate at Buyeo and Gocksung. Furthermore, there were increased populations following treatment with abamectin, cadusafos, and dazomet at Gocksung. The control effects of BA12011 treatment on plant-parasitic nematodes were confirmed to be similar to those of the other 4 nematicides evaluated, although its control effect was higher than that of fosthiazate in cucumber-growing soil at Gongju. The effects of nematicide treatment on egg mass formation in each of the collected soils differed according to the region of soil origin. Abamectin was effective in reducing the degree of egg mass formation in Buyeo and Jinju soil, whereas BA12011 was effective in Nonsan and Gocksung soil. Dazomet was found to inhibit egg mass formation in Gongju soil. To evaluate the effect of the newly developed nematicide, BA12011, experiments were conducted in a cucumber-growing greenhouse. The average population densities of Meloidogyne spp., Pratylenchus spp., and Helicotylenchus spp. after the first treatment were reduced to a greater extent than after the second treatment. It is thus suggested that early nematicide treatment is important for effective control of plant-parasitic nematodes.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.317-323
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• 2005

This study was conducted to survey plant-parasitic nematodes and their damages on Codonopsis lanceolata Trautv at 116 fields of 15 major cultivation areas in Korea. Among the 9 plant-parasitic nematode genera detected in the fields, Ditylenchus citri, Meloidogyne hapla, M. incognita, Pratylenchus neglectus, Tylenchorynchus clayton were identified. M. hapla Chitwood showing the highest field infection rate of 61.9% followed by Tylenchus spp. 16.1%, Pratylenchus neglectus 7.8%, Ditylenchus citri 5.1%, and Helicotylenchus sp. 5.1%. Average field infection rate of root-knot nematodes in 2-year-old C. lanceolata was 67.0%, and the average plant infection rate was 60.2%. The average yield decrease rate was 10%. The damage rate by the root-hot nematode increased as the cultivation year extended in Jeonbuk province, and the damage was also higher in flat land than in mountainous areas.

• Research in Plant Disease
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• v.12 no.2
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• pp.108-114
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• 2006

This study was conducted to elucidate the interactions among soil microorganisms in a special field where one, two or three of N, P, K fertilizers were continuously not applied for 29 years. Crop yield (barley, soybean), soil chemical properties and microflora and microfauna including nematodes, nematophagous fungi, actinomycetes, bacteria, and fungi were examined for two years. Tylenchorhynchus sp. was the most important plant-parasitic nematode (range $11{\sim}642/300 cm^3$ soil) followed by Pratylenchus sp. and Helicotylenchus sp. Among nematophagous fungi, Monacrosporium spp. was the most frequently found followed by Harposporium sp. and Cystopage sp. In general, plots treated with phosphate fertilizer yielded more, had more nematodes, bacteria and actinomycetes. In contrast, total fungal population densities including nematophagous fungi, Cystopage sp. and Harposporium sp. were in reverse; they were more abundant in the plots with lower phosphate contents. Phosphate and pH are positively correlated and two most important determining factors for the population density of soil organisms under investigation. According to correlation analysis, Ca, Mg, and $SiO_2$ contents in soil and population densities of Tylenchorhynchus sp., saprophitic nematodes, actinomycetes, and bacteria were positively correlated with pH, but were negatively correlated with fungal population densities. We hope that the study will add an additional knowledges to understand our mysterious underworld.