• Korean journal of applied entomology
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• v.40 no.4
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• pp.277-294
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• 2001

Four new and two known species of soil nematodes belonging the order Dorylaimida are described and illustrated. Discolaimium gyeongiens n. sp. is 1.6~1.7 mm long, c=37~41, odontostyle 19~21$\mu\textrm{m}$ long and is characterized by having wider lip region and very short prerectum. Aporcelaimellus donghwaens n. sp. is 2.8~2.9mm long, c=40.0~4.5, odontostyle 19~20$\mu\textrm{m}$ long and is characterized by possessing shorter odontophore, presence of cardiac disc and conoid tail. Labronema korandus n. sp. is 2.2~2.3 mm long, c=68~81, odontostyle 27~28$\mu\textrm{m}$, spicule 61$\mu\textrm{m}$ long and is characterized by having continuous lip region, circular vulva and cylindrical tail. Zalophidera longus n. sp. is 4.1~4.4mm long, c=107~130, spear 80~93$\mu\textrm{m}$ long and is characterized by large sized body, spear and spear extension. Discolaimoides bulbiferous and Diphtherophora communis were reported here for the first time in Korea.

• Research in Plant Disease
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• v.18 no.2
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• pp.101-108
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• 2012

In 2006, pinewood nematode, Bursaphelenchus xylophilus, was isolated from about 50 years old trees of Pinus densiflora and P. koraiensis showing leaf-wilt and -drying symptoms in Gwangju, Gyeonggi-do and Chuncheon, Gangwon-do. Isolation of pinewood nematodes from sapwood of infected pine trees showed no difference in population density between tree species and among the sampling heights on the main stem. Migration of pinewood nematodes in the host tree were investigated by inoculation of red pine (P. densiflora, 3 years old) seedlings with B. xylophilus. The nematodes seemed to move in red pine seedlings prior to multiplication and it might have taken about 20 days to start multiplication and expression of symptoms including wilt and dieback. In initial time after inoculation, nematodes started migration through the cortical resin canal from inoculated site and further showed upward and downward movements. More nematodes were observed in cortical resin canal during early period of inoculation and later in resin canal of xylem and tracheid also while, the pith still remained free from nematode. The density of B. xylophilus was higher in seedlings of low-vigor with poor root growth than in seedlings of normal root growth. Seedlings showing high density of B. xylophilus exhibited stem discoloration and secondary infection by fungus at the inoculation site.

• Korean Journal of Environmental Biology
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• v.39 no.2
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• pp.147-155
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• 2021

To investigate the incidence of plant-parasitic nematodes (PPNs) in perilla fields in Korea, 55 soil samples were collected from open fields and plastic-film house fields and were analyzed during January 2020 to October 2020. Root-lesion nematodes (RLNs), spiral nematodes, root-knot nematodes, and stunt nematodes were detected in perilla fields, and the incidences of RLNs (39%) and spiral nematodes (55%) were higher than those of other nematodes. Among PPNs, RLNs are very important species found on economic crops. The detection frequency of RLNs was increased due to continuous crop cultivation, and the frequency of fields that cultivated only one crop continuously for over 11 years was twice higher than the frequency of fields that cultivated only one crop for less than 5 years. The PPN species diversity and density were different between leaf-perilla cultivation fields and seed-perilla cultivation fields. In phylogenetic analysis of RLNs, Pratylenchus penetrans, P. vulnus, and Pratylenchoides leiocauda were identified in perilla fields. These results suggest the RLNs should be considered for establishing nematode management strategies in perilla fields in Korea.

• Korean journal of applied entomology
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• v.59 no.4
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• pp.361-369
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• 2020

This study aimed to investigate the differences in the effects of nematicidal materials (Burkholderia rinojensis, fluazaindolizine, fluopyram, fosthiazate, hydrogen peroxide, and imicyafos) on eggs and larvae of the sugar beet cyst nematode, Heterodera schachtii and clover cyst nematode, H. trifolii, which have recently become problematic in highland Chinese cabbage cultivation areas in Korea. Comparison of the hatching rates according to the test materials showed differences between treatments. In the treatment with fluopyram, fosthiazate, and imicyafos, a very high hatching inhibitory effect of 99% was observed in both nematodes, and there was no difference in the efficacy of treatments between nematode species except for that with hydrogen peroxide. Regarding the nematocidal activity of treatments against hatched larvae, only the fluazaindolizine treatment, despite showing a high hatching inhibitory effect, showed a low nematicidal effect of less than 30% against both nematodes, whereas a mortality rate of more than 90% was observed in the other treatments. There was no difference between nematode species in the reactions of the 2nd instar juveniles to all nematicidal test materials after 24 and 48 h of treatment. Although there are limitations to the laboratory experiment, the reaction to the nematicidal materials of the two cyst nematodes that damage the same host was similar, and simultaneous control is suggested in the areas where the two nematodes occur together.

• Korean journal of applied entomology
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• v.25 no.3 s.68
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• pp.175-182
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• 1986

A study was conducted to survey the fauna and the field density ofp lant parastic nematodes on important cash crops in Korea. Studies were carried out with sampling about five hundred grams of soil around roots of eighteen different kinds of crops from fifty five locations throughout the country. Nematodes were elutriated from over three thousand soil samples, and identified into sixteen different genera. Among them Ditylenchus species were found to be the most abundant in fields of garlic and onion, Helicoty-lenchus of sesame, chinese cabbage and mulberry, Meloidogyne of red-pepper, tomato, cucumber and peanut, Pratylenchus of mulberry and peach, Pratylenchus of apple, Chinese cabbage and radish, Trichodorus of potato, and Xiphinema of peach and potato. Field density of Meloidogyne species was increased with the longer continuous cultivation of red-pepper in the same field.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.101-111
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• 2012

Soybean cyst nematode(SCN) (Heterodera glycines Ichinohe) causes the greatest yield loss to soybean compared to any other pest worldwide. Yield loss due to SCN is estimated 7.6 million megagrams in the USA and nearly 9 million worldwide. SCN causes yield reductions by feeding on plant nutrients, retarding root growth, and inhibiting Bradyrhizpbium japonicum(Kirchner) Buchanan nodulation. The primary methods for controlling SCN include planting resistant cultivars and rotation with nonhost crops. Genetically diverse field populations of SCN combined with the limited germplasm base of commercial soybean for resistance could potentially leads to population shifts over time, and this makes controlling H. glycines more difficult. This paper reviewed the importance of soybean, soybean cyst nematode, researches on resistance to SCN, and prospects. Tremendous effort must still be endeavored for elucidating resistance mechanisms and managing H. glycines in the soybean field.

• Korean Journal of Plant Resources
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• v.16 no.3
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• pp.200-206
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• 2003

This study were conducted to assess plant­parasitic nematodes infesting Codonopsis lanceolata. Ten kinds of plant­parasitic nematode gem including Meloidogyne and Pratylenchus were identified in 34 localities of C. lanceolata fields in three provinces in Korea. Meloidogyne, a dominant genus, was found in 97％ localities and showed high average density as 1,700 nematodes per 300$m\ell$ soil. Its average density was 10 times higher in upland field than in paddy field.

• Asian Journal of Turfgrass Science
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• v.12 no.2
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• pp.107-112
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• 1998

우리나라 골프장의 잔디 가해 해충과 천적을 조사하던 중 농림작물의 중요해충인 고구마뿌리혹선충을 Zoysia잔디에서 발견하였다. 고구마뿌리혹선충에 감염된 잔디는 새 뿌리가 발육하지 못하고 뭉툭하게 되어 황화현상과 함께 전반적으로 생육이 부진하였다. 감염된 잔디의 종은 들잔디(Zoyais japonica)와 금잔디(Zoysia matrella), 버뮤다글라스(Cynodon sp.)였다. 그리고 Z. japonica는 고구마뿌리혹선충의 새로운 기주로 기록된다. 조사 골프장의 대부분이 정도의 차이는 있었지만 피해를 받고 있었다. 잔디에서 뿌리혹선충이 기록되기는 우리나라에서는 처음이다.

• Korean journal of applied entomology
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• v.41 no.4
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• pp.293-298
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• 2002

Cadusafos and fosthiazate were applied at the rate of 1.8 g a.i./6$\m^2$ as pre-plant or pre-plant＋post-plant treatments on winter-grown oriental melon in a greenhouse soil infested with Meloidogyne arenaria. Nematicides reduced root-knot nematode population from 35 to 90% compared with control； fosthiazate was better than cadusafos (P ＝ 0.003) and fosthiazate pre-plant＋post-plant application reduced nematode population densities as much as 90%. Nematicides increased yield in an average of 23% (11-38%) in May, 39% (2-65%) in June, and 31% (12-46%) for the total (P ＝ 0.085). The residue in the fruit of oriental melon by post-plant treatment of fosthiazate exceeded maximum residue limit of 0.2ppm, while the Cadusafos residue was below the limit. It is concluded that fosthiazate cannot be used as a post-plant treatment in winer-grown oriental melon with overall consideration, i. e., danger of residue, value of melon, costs of nematicide, consumer demand on safer agricultural products, and effects of fallow.

• Korean journal of applied entomology
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• v.31 no.4
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• pp.396-415
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• 1992

To investigate identification of species distribution state, population density of plant parasitic nematodes and damaged state by parasitism of nematodes with soil samples taken from major cultivating area of medicinal herbs in Kyungbuk districts are summarized as follow; total species belonging to genera in families were identified from 43 different medicinal herbs. The dominant nematode species on medicinal herbs was Meloidogyne hapla by 55.6% of field infection. Damaged state by parasitizm of Root-knot nematode, M. hapla, M. incognita are severed 15 medical plant except P. japonica, infected field were in 54.5~88.0%, and highered in population densities of 2nd larvae, Gall, Egg sac. Percentage of yield-decrease were 57.8% in A. gigas, 49.1% in P.japonica. Lighten effect of M. spp. by cropping system were lowered in population density in Rice+Paeony than Paeony+Paeony in paddy field, and also lowered in Sesame+Paeony or one year fallowing after harvest Paeony than Red pepper+Pseony, Paeony+Paeony in upland field.