• Korean journal of applied entomology
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• v.58 no.1
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• pp.9-13
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• 2019

Nematode-trapping fungi use various specialized traps to capture nematodes. A fungus that can capture nematodes in three dimensional adhesive networks was isolated from the soil around the root of Cucumis melo L. (Oriental melon) in Seongju, Korea. The conidiophores were found to be septate, hyaline, erect and $290-528(342.8){\mu}m$ high. It produces obovoid shape and 1-3 septate (commonly 2-septate) conidia with a size of $30.5{\times}20.3{\mu}m$. Molecular analysis of 5.8 S rDNA displayed 99% similarity to Arthrobotrys sinensis. On the basis of morphological, morphometric and molecular studies, the fungus was identified as A. sinensis. It is the first report in Korea which can be one of biological control resource of plant-parasitic nematode.

• Korean journal of applied entomology
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• v.39 no.2
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• pp.111-115
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• 2000

Fifty-two nematode predatory fungi were isolated from 37 soil samples collected from eight provinces in Korea. Isolated fungi were tested their predacity against Rhabditis sp. and Meloidogyne incognita in petri dish, and against M. incognita in greenhouse pot experiments. Fifty isolates had trapping organ of adhesive networks and two isolates had adhesive column or adhesive knob. In petri dish experiments, 5 1 isolates against Rhubditis sp. and 26 isolates against M. incognita showed over 91 % of predacity; in greenhouse experiments, however, only three isolates showed over 81% of predacity. These results imply that the results from the laboratory experiments are not consistent with those from the greenhouse experiments. Therefore, to select a promising biocontrol predatory fungi for plant-parasitic nematodes, the screening experiment should be conducted in conditions close to nature.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.210-211
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• 2007

Dactylella pseudoclavata that captures nematodes in adhesive networks was isolated from nematode-infested strawberry plants from Andong, Korea. It produces obclavate, 0-1 septate conidia, $30-40{\mu}m$ long and $8-11{\mu}m$ wide, with round distal ends and bases shaped like bottle-necks. The conidiophores were simple, occasionally branched, $150-300{\mu}m$ long, producing 1-4 conidia at the apex. Chlamydospores were abundant, intercalary or catenulate, yellowish to brown, globate or subglobate, wart on the surface, $30-35{\times}25-30{\mu}m$ in size. This is the first report of Dactylella pseudoclavata in Korea.

• Korean Journal of Microbiology
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• v.21 no.3
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• pp.127-134
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• 1983

42 strains belonging to the genus Arthrobotrys and 17 strains belonging to the genus Monacrosporium, were isolated from soil specimens collected from the various localities in South Korea. 4 species of Arthrobotry and 2 species of Monacrosporium, which are unrecorded in Korea, were identified according to the Harrd and Cooke classification key, respectively. The species identified are as follows ; A.conoides, A. oligospora, A. musiformis, A. oviformis, M. crystosporum nd M. salinum.

• 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.

• The Plant Pathology Journal
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• v.22 no.2
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• pp.174-178
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• 2006

Monacroporium ullum sp. nov. the captures nematodes on adhesive spherical knobs was isolated from soil around Codonopsis lanceolata at Ulleung island, Korea. The spindle-shaped conidia sized $17-44{\mu}m\;(26.5{\mu}m)\;long,\;7-10{\mu}m\;(8.1{\mu}m)$ wide, containing from 1 to 4 cross-walls but most often divided by 2 septa (47%). Resting bodies sized $57{\times}30{\mu}m$. Arthrobotrys amerospora has almost spherical non-septate conidia with a small truncate protuberance at the base and sized $20-27{\mu}m\;(23.3){\mu}m$ long and $11-17{\mu}m\;(14.1){\mu}m$ wide. Conidiophores are somewhat longer $362.8{\mu}m\;(311-418{\mu}m)$ than its original description ($75-250{\mu}m$).

• Mycobiology
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• v.33 no.4
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• pp.194-199
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• 2005

Application of fertilizers such as urea, diammonium phosphate (DAP) and muriate of potash in soil adversely affected the spore germination of Arthrobotrys dactyloides. Amendment of soil with urea at the concentrations of 1.0%, 0.5% and 0.1 % completely inhibited spore germination and direct trap formation on the conidium, whereas muriate of potash delayed and reduced the spore germination even at the lowest concentration. DAP also inhibited spore germination at 1.0% concentration, while at lower concentration the percentage of spore germination was reduced. Application of neem cake at the concentration of 0.5% also inhibited spore germination after 24 h of amendment. The inhibitory effect of neem cake was reduced after 15 days of amendment, while after 30 days after amendment the inhibitory effect was completely lost and the spore germinated by direct trap as in unamended soil. Nematodes were not attracted to ungerminated spores after 24 h of amendment. After 15 days of amendment nematodes were attracted to agar blocks containing fewer germinated spores after 24 h of incubation but after 48 h of incubation large number of nematodes were attracted and trapped by the germinated spores with direct traps. After 30 days of amendment, larger number of nematodes were attracted and trapped by direct traps.

• Mycobiology
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• v.33 no.4
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• pp.215-222
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• 2005

Variability in growth and sporulation of five isolates of Arthrobotrys dactyloides was studied on five agar, 6 bran and 5 grain media. Potato dextrose agar (PDA) supported maximum growth of isolate A, C and E, while growth of isolate Band D was significantly lower on this medium. On Czapek's agar and yeast glucose agar media the differentiation in the isolates in relation to growth was poor than PDA. The other two media showed much poorer differentiation. On Czapek's agar medium, sporulation was recorded in isolate B only, whereas other isolates showed rare sporulation. Among the bran media, pea bran agar medium supported maximum growth of all the isolates except isolate B. Gram and rice bran agar media were next best. However, the growth of isolate B on the gram bran agar medium was more or less equal as other isolates. On pigeon pea bran agar medium, isolate E failed to grow while other isolates recorded poor growth. On lentil bran agar medium, only isolate Band D recorded little growth, whereas other isolates failed to grow. All the isolates recorded good sporulation on bran agar media except pigeon pea and lentil bran agar media. The grain agar media supported moderate to very good growth of all the isolates. In general isolate B remained slow growing on these media except gram grain and sorghum grain agar media on which growth of this isolate was comparable to other isolates. Sporulation in general, was good on all the grain agar media. Among different substrates screened, barley grain and pea bran were found superior to others for mass culture of isolate A of A. dactyloides.

• Korean journal of applied entomology
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• v.51 no.1
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• pp.9-18
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• 2012

The size of infective $Steinernema$ $arenarium$ juveniles is variable and ranges from 724 to 1408 ${\mu}m$. Effects of harvest time and infective juvenile size on pathogenicity, development, and reproduction were examined in the last instar of the great wax moth, $Galleria$ $mellonella$. Harvest time of infective juveniles (IJs) of $S.$ $arenarium$ affected pathogenicity. IJs harvested at the 10th day from trapping were more pathogenic than those harvested the 3rd day from trapping. Mortality of $G$. mellonella also depending on harvest time, $i.e$, 100% died within 48h when IJs were harvested at the 10th day, without relation to size. However, mortality was 40% in the small size group (SSG) compared with 18% in the large size group (LSG) within 48h when IJs were harvested at the 3rd day. Establishment of $S.$ $arenarium$ within the host was different depending on IJ size. The number of established IJs was 1.8 in the SSG, 3.3 in the LSG, and 3.2 in the mixed size group (MSG) when IJs were harvested at the 3rd day, and 5.3 in the SSG, 7.4 in the LSG, and 7.6 in the MSG when IJs were harvested at the 10th day. The length of the female adult was 7,070.5 ${\mu}m$ in the SSG and 7,893.9 ${\mu}m$ in the LSG and that of the male was 1,460.5 ${\mu}m$ in the SSG and 1,688.2 ${\mu}m$ in the LSG when IJs were harvested at the 3rd day. The length of the female adult was 7,573.6 ${\mu}m$ in the SSG and 8,305.4 ${\mu}m$ in the LSG and that of the male adult was 1,733.4 ${\mu}m$ in the SSG and 1,794.4 ${\mu}m$ in the LSG when IJs were harvested at the 10th day. Harvest time and size of IJs did not influence numbers of progeny or size of IJS.