• Ocean Science Journal
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• v.41 no.3
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• pp.163-173
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• 2006

A draconematid nematode species, Dracograllus filipjevi Allen and Noffsinger, 1978, is described from the washings of shallow littoral coralline algae at Guryongpo in the eastern coast of Korea. This species is recognized by the following characteristics: larger body size, number of posterior sublateral adhesion tubes (9 in male and 12-13 in female) and subventral adhesion tubes (8-9 in male and 9-10 in female), the absence of cephalic acanthiform setae on rostrum, the presence of longitudinally areolated body cuticle with dot-like punctations, the presence of some cuticular collar in swollen pharyngeal region, the shape of amphidial fovea (large, elongate, and loop-shaped in both sexes), the absence of preanal corniform setae, and the absence of lateral differentiation on narrow body region. Morphological features of the species using differential interference contrast photomicrographs are described in detail in the present work. The is the first report of D. filipjevi in Korea.

• Animal cells and systems
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• v.9 no.3
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• pp.113-122
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• 2005

A new species of free-living marine draconematid nematode, Dracogalerus koreanus n. sp., is described from the shallow subtidal coarse sediments and various invertebrates of Jeju Island, Korea. This is the first record of this genus from Korea. Dracogalerus koreanus n. sp. is morphologically most similar to D. cryptocephalus (Irwin-Smith) in having similar head shape (rostrum broadly rounded anteriorly) and eight cephalic adhesion tubes, but differs by the small number of rounded protuberances on the ventral side of non-annulated tail end (5 vs 6), small number of posterior subventral adhesion tubes in male (5-6 vs 8), intermingled somatic setae (5-6 vs absent), spicules (slightly curved and relatively thick vs strongly curved and very slender), and higher 'c' value in male (8.8 vs 7.5).

• Animal cells and systems
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• v.14 no.1
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• pp.31-36
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• 2010

The pinewood nematode Bursaphelenchus xylophilus causes pine wilt disease and is a serious economic concern for the forest industry of South Korea. To achieve effective control with limited resources, it is necessary to clarify the transmission routes and mechanisms of dispersal of this organism. Highly polymorphic and easy-to-use molecular markers can be used for investigating this aspect. In this study, we evaluated the usefulness of amplified fragment length polymorphisms (AFLPs) for investigating the genetic variations of B. xylophilus and related individuals from China, Japan, and South Korea. The AFLP patterns obtained in our study were similar to the microsatellite patterns reported in a previous study; our AFLP patterns indicated high genetic variability and cryptic genetic structure, but did not indicate any peculiar geographic structure. Moreover, the genetic distances between individuals suggested that the Korean population was affected to a greater extent by the Chinese population than the Japanese population. Further, the gene flow among the related species appeared to be limited; however, there may be also the possibility of genetic introgression among species. These results confirm the usefulness of AFLPs for understanding the epidemiology of pine wilt disease, thereby contributing to the effective control of this disease.

• Mycobiology
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• v.31 no.1
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• pp.9-18
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• 2003

A total of 82 genera and 271 species of soil-inhabiting fungi including saprobic, nematode-trapping, and arbuscular mycorrhizal but plant pathogenic fungi published hitherto in South Korea are listed with the information on geographic location, habitat, vegetation when available, and relevant literatures.

• The Plant Pathology Journal
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• v.21 no.1
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• pp.83-85
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• 2005

Ditylenchus acris was isolated from diseased strawberry plants. Frequently, D. acris and Aphelenchoides fragariae occur together in a strawberry plant. Both species appeared very similar in the shape, length, swimming behavior and causing symptoms, and difficult to distinguish them by a stereomicroscope. But they were easily distinguished under a compound microscope especially by their tail shape, median bulb, vulva position, and bursa.

• Korean journal of applied entomology
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• v.36 no.2
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• pp.119-125
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• 1997

In a survey of spiral nematode (Hoplolaimidae) in Korea, Helicotylenchus cavenessi sher, 1996, Helicotylenchus paraplatyurus Siddiqi, 1972, Rotylenchus alius Van den Berg, 1986 and Rotylenchus incultus Sher, 1965 were newly found and recorded in Korea.

• The Plant Pathology Journal
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• v.34 no.4
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• pp.308-315
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• 2018

Root-knot nematodes 'Meloidogyne spp' are the most destructive group of plant parasitic nematodes causeing serious losses in vegetables crops and this damages worsened when crops grown under greenhouses conditions. In this sutdy, the distribution and characterization of root-knot nematode species collected from the Souss region of Morocco where vegetables crops intensively cultivated were determined by using both morphological and molecular tools. Out of the 110 samples collected from different greenhouses 91 (81.7%) were found to be infested with root-knot nematodes. Thirty-seven populations of root-knot nematodes were morphologically identified based on perineal patterns as well as molecularlly using species-specific primers. The obtained results indicated that Meloidogyne javanica and M. incognita were identified in 86.4% and 13.5% of the total populations, respectively. The lowest incidence of root-knot nematodes (64%) was found in Toussous, whereas the highest frequencies of 100% and 90% were detected in Taddart and Biogra, respectively. As the majority of the samples have been infested with Meloidogyne species; this indicates that there is an urgent need to provide farmers with a proper control strategy.

• 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 Environmental Biology
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• v.38 no.4
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• pp.578-585
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• 2020

A new free-living marine nematode species of the genus Belbolla Andrássy, 1973 belonging to the family Enchelidiidae is described based on specimens collected from the sediment of a subtidal benthic environmental habitat in the East Sea, Korea. Belbolla wonkimi sp. nov. differs from its congeners by the combination of the following characteristics: a relatively long body (3263-3396 ㎛), the absence of ocelli, nine oesophageal bulbs in the posterior pharynx, well-developed two winged precloacal supplements, longer spicule length(115-130㎛, 1.6-1.8 anal body diameter long), and a triangle-shaped shorter gubernacular apophysis (17-18 ㎛). Comparative tables on the biogeographical and morphological characteristics of Belbolla species are presented. A DIC (differential interference contrast) photomicrograph of the new species is also provided. This is the first taxonomic report on the genus Belbolla from Korean waters.

• Mycobiology
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• v.41 no.1
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• pp.59-62
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• 2013

Japanese pine sawyer beetle (Monochamus alternatus) is an economically important pest in coniferous trees. Ophiostoma ips was isolated from the beetle and identified based on analysis of morphological properties and the ${\beta}$-tubulin gene sequence. The fungus easily produced perithecia with a long neck on malt extract agar and its ascospores were rectangular shaped. This is first report of Ophiostoma species associated with the pinewood nematode vector beetle in Korea.