• Korean Journal of Environmental Biology
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• v.21 no.3
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• pp.271-275
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• 2003

The direct count and MPN (Most Probable Number) methods were used to measure the number of nematodes in soils collected from cultivated and non-cultivated fields. As a result, the number of nematodes from cultivated soils was higher than the non-cultivated soils (NC -1, NC -2). On the other hand, upon measuring the value from the organo farming cultivated soils (OC, OR) and conventional cultivated soils (CC, CR), the former showed 16 times higher than the latter. These results indicate that nematode population which can multiply in the organic compounds abundantly exist in the organo farming cultivated soil. Isolated entomopathogenie nematodes are composed of two orders, which were Rhabditida and Diplogasterida. To determine the pathogene-city of them using the 5th larvae and pupae silkworm, and the following mean $LD_{90}$ values were found: 24 to 30 hours in Rhabditida and 36 to 48 hours in Diplogasterida nematode, respectively. This study indicates that nematodes are sensitive to this kind of environmental disturbance. Isolated entomopathogenic nematodes were suggested that aye quite within the realms of possibility for biological control agents.

• Korean journal of applied entomology
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• v.24 no.1 s.62
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• pp.39-44
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• 1985

This study was undertaken to select a suitable Korean tissue paper for Baermann funnel method. Ten kinds of five manufacturers were evaluated as to nematode extraction efficiency in Baermann funnel. 'Crown Hankie'(Korea Special Paper Co., Ltd.) had suitable properties in nematode permeability and strength regardless of three soil types, loamy sand, sandy loam and clay loam. The number of nematodes extracted using 'Crown Hankie' 4 ply was 198, while that of 'Cottonwool Nematode Filter' was 227. Un-perfumed tissue papers showed higher nematode extraction efficiencies than perfumed tissue papers by 53 and 23% in 'Kleenex New Softness' and 'Monaliza Finely Soft Tissue', respectively. Among the nematode extraction efficiencies by temperatures, $15^{\circ},\;25^{\circ}\;and\;35^{\circ}C$, it was highest at $35^{\circ}C$. In experiment of evaluating nematode extraction using Baermann funnel at 12 hours interval to 92 hours, 35.3 and 40.3% of nematodes were extracted after 12 and 24 hours, respectively.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.56-65
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• 2016

Pine wood nematode, Bursaphlenchus xylophilus is a fatal damaging pest, infecting pinewood trees and is one of the serious forest pest in Korea. Trunk injection is one of the most effective method to protect the live pine trees from nematode infection. The aim of this research was to reveal the efficacy of the nematicidal materials from 46 Kyrgyzstan, 88 Vietnam plant materials and 21 active materials (${\alpha}$-terpinene, ${\alpha}$-pinene, ${\beta}$-thujaplicin, cinnamaldehyde, eugenol, emodin, geraniol, limonone, methyl palmitate, matrine, myrcene, methyl gallate, nicotine, quassin, resveratrol, rotenone, thymol, thujaplicin, terthiophene, tuberstemonine, ${\gamma}$-terpinene) isolated from plants for using as trunk injection agents. Eclipta prostrata extract was highly effective against pine wood nematode in plant extracts and terthiophene has the best nematicidal activity from active materials isolated from plants. Foliar spray of terthiophene on Japanese black pine (Pinus thunbergii) tree reduced proliferation of inoculated pine wood nematode at 22 days after treatment, however no efficacy was found over 22 days. Eclipta prostrata extract and terthiophene can be used as nematicide for further nematicidal efficacy test against any other plant parasitic nematodes and trunk injection efficacy against pine wood nematode.

• Korean journal of applied entomology
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• v.58 no.1
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• pp.37-47
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• 2019

A survey on the geographical distribution of two soybean cyst nematodes, Heterodera glycines and Heterodera sojae, was conducted in soybean cultivation areas in the Gangwon-do and Chungcheongbuk-do provinces. In 67 fields of 10 counties or cities in Gangwon-do province, H. glycines was detected in 13 fields, H. sojae was detected in five fields, and both species were found in two fields. In 84 fields of nine counties or cities in Chungcheongbuk-do province, H. glycines was detected in 27 fields, H. sojae was detected in four fields, and both species were found in five fields. The diversity and dominance of the plant parasitic nematodes in the Gangwon and Chungbuk provinces were not significantly different among the soybean cultivars. The diversity and dominance index of the plant parasitic nematodes according to the presence or absence of soybean cyst nematodes did not show any significant difference between the soybean cultivation areas of both provinces. The relationship between the soybean cyst nematodes and soil chemical properties showed a low coefficient of determination, and the density of soybean cyst nematodes tended to increase as the pH and available phosphate content in soil samples increased. The soil texture of cyst nematode-detected fields was mostly sandy soils, which amounted to about 60% of the total. As the clay and silt content increased, the density of soybean cyst nematodes tended to decrease, and as the sand content increased, the density of cyst nematodes tended to increase.

• Korean journal of applied entomology
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• v.38 no.3
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• pp.249-253
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• 1999

To study races of Heterodera glycines in Korea, 21 soil samples were collected from eight provinces in 1995. Four races were found; race 3(48%) was a dominant race flowed by race 5(24%), race 1(19%), and race 6(9%). About 30~40% of H. glycines populations reproduced on Pickett and PI88788, while non reproduced on Peking or PI90763. Development of resistant soybean cultivar targeting to race 5 and 6 of H. glycines using PI90763 and PI88788 as a parent is recommended.

• Journal of Sericultural and Entomological Science
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• v.29 no.1
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• pp.48-52
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• 1987

The fauna and the distribution of plant parasitic namatodes were investigated by smapling about five hundred grams of soil around roots of mulberry trees from 929 mulberry fields in Korea. Of fourteen genera detected on mulberry fields, Paratylenchus aciculus, P. projectus, P. morius, Helicotylenchus dihystera, Meloidogyne arenaria were found to be parasitic to mulberry. Among them Paratylenchus species were the most abundant in mulberry fields, but Tylenchorhynchus sp., Aphelenchus sp., Helicotylenchus sp., and Meloidogyne sp. were also observed in high frequency. Meloidogyne species were observed in high frequency in Jeonbuk, Gyeonggi and Jeonnam, Helicotylenchus sp., in Gyeongnam and Gyeonggi, Xiphinema sp., in Jeonbuk and Jeonnam, and Paratylenchus sp., in Gyeonggi, Gyeongbuk, Gyeongnam, and Jeonnam. The growth of mulberry was poor as the increase of density of Paratylenchus sp.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.291-301
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• 2019

Nematophagous fungi can capture, kill, and digest nematodes using a specific capturing organ. Of the nematophagous fungi, while Arthrobotrys flagrans and A. superba have been described previously, certain characteristics have not been described. For a detailed description of the two nematophagous fungi, the fungi were isolated from soil samples and produced in a pure culture. Morphological characteristics, such as predatory ability (according to the nematode species), shape, and size of predatory organ, conidia, and chlamydospore were investigated and they were used for identification of the fungal isolates along with molecular phylogenetic analysis. Furthermore, this study provides the classification key for 21 nematophagous species.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.535-539
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• 2009

This study was conducted to identify plant-parasitic nematodes and determine the distribution pattern of the nematode species in citrus fruit orchards in Korea from April to August, 2008. Plant-parasitic nematodes were found in 139 among 178 soil samples. Tylenchulus semipenetrans was collected from 85 out of 94 Citrus unshiu orchards examined (90.4%). C. junos orchards infested with T. semipenetrans were 60 out of 84 (71.4%). However, proportion of dominant species between the two was different. At domestic Citrus orchards, it proved that T. semipenetrans was the most important plant-parasitic nematode from this study. The overall frequency of the plant-parasitic nematodes was positively correlated with the cultivation years. More alkaline soils tended to harbor more T. semipenetrans. However the correlation coefficient between the two was very low.

• Research in Plant Disease
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• v.14 no.1
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• pp.76-78
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• 2008

During the investigation of Allium decline in Pohang, Korea, root-knot nematode was found from root of Allium tuberosum Roth. It was identified as Meloidogyne incognita and was first reported from Allium tuberosum. Allium decline was associated with root-knot nematode, root mite and Fusarium sp. but root-knot nematode appeared to be the main cause of Allium decline.

• Research in Plant Disease
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• v.23 no.4
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• pp.348-354
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• 2017

To investigate occurrence of root-knot nematode (RKN) in plastic house of central area of Korea, 132 soil samples were collected in cucumber, water melon, tomato, red pepper and strawberry fields from 2013 to 2015. Among 132 soil samples, 65 soil samples (49%) were infested with RKN and mean density of RKN was 178 second-stage juveniles per $100cm^3$ soil (min. 1 ~ max. 3,947). The frequency of RKN by regional was the highest in Chuncheon with 80%, followed by Cheonan (68%), Nonsan (36%), Buyeo (33%) and Yesan (30%). The frequency of RKN by crops was the highest in tomato with 83%, followed by cucumber (61%), strawberry (41%), red pepper (30%), watermelon (26%). To identify the species of RKN, fifteen populations were selected for representative populations. As a phylogenetic analysis of 15 populations, southern root-knot nematode (Meloidogyne incognita), peanut root-knot nematode (M. arenaria) and northern root-knot nematode (M. hapla) were identified with 47%, 20% and 33% ratio, respectively. In crops, M. incognita, M. arenaria and M. hapla were detected in tomato, M. incognita and M. arenaria were detected in cucumber and watermelon, and M. hapla was detected in strawberry and lettuce. Thus, there should be a continuous management to major species of each crops to prevent dispersal of RKN damages.