• Korean journal of applied entomology
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• v.22 no.4 s.57
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• pp.251-261
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• 1983

Survey on soybean parasitic nematodes has been undertaken in order to get an ideas about the distribution of nemic fauna. Total 71 soil samples were collected from soybean fields in Gyeongbug and Chungbug provinces. Eighteen species belonging to fourteen different genera were found associated with soybean, Glycine max. The results were as follows: Aphelenchus avenae, Circonemoides informis, Ditylenchus dipsaci, Helicotylenchus pseudorobustus, Heterodera glycines, Hirschmanniella imamuri, Meloidogyne hapla, Meloidogyne incognita, Paratylenchus pandus, Pratylenchus thornei, Pratylenchus vulnus, Psilenchus hilarulus, Rotylenchus sp. Tylenchorhynchus clay toni, Tylenchorhynchus dubius, Tylenchorhynchus nudus, Tylenchus sp. Xiphinema americanum were found in soybean fields. In frequency of occurring nematodes by localities, soybean cyst nematode was higher in Chungbug by $70\%$, while $50\%$ in Gyeongbug. But rook-knot nematode was higher in Gyeongbug by $54.1\%$, while $19.1\%$ in Chungbug. In density of nematode, Heterodera was the most dominant as 200.4 populations per 100ml soil, Meloidogyne as 107.1 populations, Rotylenchus, Xiphinema, Aphelenchus in decreasing order. In survey of loss, density of soybean cyst nematode in heavily infested fields was 155 cysts per 100ml soil while 35 cysts in slightly infested fields. Seventy percent of soybean yields was decreased when comparing with average 64.2kg/10a in heavily infested fields and average 209.5kg/10a in slightly infested. Correlation coefficients among number of soybean cyst and yields, pod weight, number of pod was negative as r- 0.57, 0.47, 0.38 over all localities.

• 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.

• 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 Medicinal Crop Science
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• v.12 no.5
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• pp.355-359
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• 2004

A survey was conducted during $April{\sim}May$ 2004 to determine the occurrence and population density of plant-parasitic nematodes in ginseng (Panax ginseng C.A. Meyer) growing fields, in major ginseng growing regions of Chungbuk, Chungnam, Gyeongbuk and Kyongki provinces. The survey revealed presence of eleven species of plant-parasitic nematodes namely, Criconemoides morgensis, Ditylenchus destructor, Helicotylenchus dihystera, Meloidogyne incognita, M. hapla, Paratylencgus lepidus, Pratylenchus penetrans, Psilenchus hilarulus, Trichodorus similis, Tylenchorhynchus claytoni and Xiphinema americanum. Frequency and density of each species were highly variable. M. incognita and M. hapla were the predominant species, their infestation observed in 46.3 and 39.4% fields with an average density of $78{\sim}254\;and\;76{\sim}211$ nematodes per $300\;cm^3$ soil, respectively. Whereas, T. similis and X. americanum were rarely observed; only in 2.3 and 1.8% of surveyed fields and their density was $10{\sim}17\;and\;7{\sim}10$ individuals per $300\;cm^3$ soil, respectively. They are recorded herewith for the first time from ginseng fields of Korea. In nematode-infestated fields, stunted plant growth with chlorotic leaves, and wilted plants were observed in patches.

• 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 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.40 no.3
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• pp.272-281
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• 2024

Field surveys were conducted to assess the occurrence and diversity of plant-parasitic nematodes (PPNs) in golf courses and athletic fields across Maryland, USA, during 2022 and 2023. A total of 28 golf courses and ten athletic fields were surveyed, revealing the prevalence and abundance of 13 PPNs taxa in the region. Criconemoides was identified as the most prevalent (94.9%) and Tylenchorhynchus as the most abundant (2.3) across all samples. Central golf courses (west side of the Chesapeake Bay) exhibited a high prevalence of Criconemoides and Tylenchorhynchus, while Eastern Shore golf courses and athletic fields displayed a higher prevalence of Helicotylenchus and Criconemoides. Further, Belonolaimus longicaudatus was reported for the first time from turfgrass in Maryland, raising concerns due to its potential to cause severe damage on both cool- and warm-season turfgrass. Biodiversity analysis indicated that richness (R²) was higher in athletic fields, while diversity (H') and evenness (J') were significantly greater in golf courses. This study provides baseline information for monitoring PPNs distribution in Maryland and also for the development of effective nematode management approaches in turfgrass ecosystems.

• Korean journal of applied entomology
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• v.15 no.3 s.28
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• pp.133-136
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• 1976

In order to survey the kinds and distribution of tobacco parasitic nematodes, 51 soil samples were. collected from 14 associations under the office of Monopoly of Kyungbuk and Kyungnam province. 1, The plant parasitic nematodes were found $96.1\%$ in the whole sampled. 2. The propotion of infested field of each nematode genera, Tylenchus shown as dominant by $82.3\%$ and next Aphelenchus $72.5\%$, Tylenchorhynchus $58.8\%$, Meloidogyne$50.9\%$, Criconemoides $25.4\%$, Pratylenchus, Hirschmanniella $23.5\%$ in order. 3. The density of genera per localities were as follows Pratylenchus is most abundant in Youngdeog as 43 population, Tylenchorhynchus shown in Jinbo, Tylenhus in Yeongil, Meloidogyne in Kimcheon, Xiphinema in Euisung. 4. Eighteen species belonging to 16 different genera of 11 families were identified, 12 of them are new for Korea as tobacco parasitic nematodes; Aglenchus costatus, Aphelenchus avenae, Criconemoides informis, Ditylenchus dipsaci, Helicotylenchus dihystera Hirschmanniella imamuri, Meloidogyne incognita, Psilenchus hilarulus, Rotylenchus pini, Tylenchorhynchus claytoni, Tylenchorhynchus nudus and Xiphinema americanum.

• 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.31 no.1
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• pp.50-68
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• 1992

The results of survey on the nematodes associated with sapling from 8 Forestry Experiment Stations(F.E.S.) in Korea are reported herein. A total of 35 species under 20 genera, 11 families, and 2 orders were identified from the soils around the roots of 119 tree species and amongst them, Xiphinema insigne is unrecorded species for Korea and Geocenamus sp. is a new species. Tylenchorhynchus claytoni, which showed the highest detection rate (D.R.) from all F.E.S., except Nambu F.E.S, was the dominant species among the nematodes associated with saplings. The D.R. of T. claytoni was the highest in Ch’ungnam F.E.S. by 100% from 15 saplings sampled, followed by 87.5% in Kangwon, 66.6% in Kyongbuk, 58.3% in Cheonbuk, 48.1% in Ch’ungbuk, 41.3% in Kyongki, and 40% in Cheonnam F.E.S. Other important nematode species which showed very high densities by stations are; Criconemella morgensis (D.R.: 37.5%), Helicotylenchus digonicus (D.R. : 35%), Pararotylenchus pini (D.R.: 37%), Tylenchorhynchus nudus (D.R.: 37.9%), Criconemella informis (D.R.: 27.5%), and Meloidogyne sp. (D.R.: 12.5), from Chunbuk, Chunnam, Ch’ungbuk, Kyongki, and Kangwon F.E.S., respectively.