• 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 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.

• 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.

• Journal of Microbiology and Biotechnology
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• v.18 no.5
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• pp.852-858
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• 2008

An extracellular protease (Mc1) was isolated from the nematode-trapping fungus Monacrosporium cystosporium by gel filtration, anion-exchange, and hydrophobic interaction chromatographies. This protease had a molecular mass of approximately 38 kDa and displayed an optimal activity at pH 7-9 and $56^{\circ}C$ (over 30 min). Its proteolytic activity was highly sensitive to the serine protease inhibitor PMSF (phenylmethylsulfonylfluoride, 0.1 mM), indicating that it belonged to the serine-type peptidase group. The Michaelis constant ($K_m$) and $V_max$ for substrate N-Suc-Ala-Ala-Pro-Phe-pNA were $1.67{\times}10^{-4}\;M$ and 0.6071 $OD_{410}$ per 30 s, respectively. This protease could degrade a broad range of substrates including casein, gelatin, BSA (bovine serum albumin), and nematode cuticle. Moreover, the enzyme could immobilize the free-living nematode Panagrellus redivivus and the pine wood nematode Bursaphelenchus xylophilus, suggesting that it might playa role in infection against nematodes. The encoding gene of Mc1 was composed of one intron and two exons, coding for a polypeptide of 405 amino acid residues. The deduced amino acid sequence of Mcl showed 61.4-91.9% identity to serine proteases from other nematode-trapping fungi. Our results identified that Mcl possessed biochemical properties including optimal reaction condition and substrate preference that are different from previously identified serine proteases.

• 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.

• 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.