• Journal of Microbiology
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• v.43 no.1
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• pp.17-20
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• 2005

Poria cocos, a famous traditional Chinese medicine, was found to have nematicidal activity in experiments searching for nematicidal fungi. The experiment showed it could kill 94.9% of the saprophytic nematode, Panagrellus redivivue, 92.6% of the root-knot nematode, Meloidogyne arenaria, and 93.5% of the pine nematode, Bursaphelenchus xylophilus, on PDA plate within 12 hours. According to the nematicidal activity, three new compounds, 2, 4, 6-triacetylenic octane diacid, 2, 4, 5, 6-tetrahydroxyhexanoic acid and 3, 4-dihydroxy-2-keto-n-butyl 2,4,5,6-tetrahydroxyhexanate, were isolated from submerged cultures of Poria cocos. Of these, 2, 4, 6-triacetylenic octane diacid could kill 83.9% Meloidogyne arenaria and 73.4% Panagrellus redivivus at 500 ppm within 12 hours. Here, it is reported for the first time that Poria cocos has nematicidal activity.

• The Plant Pathology Journal
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• v.23 no.4
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• pp.318-321
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• 2007

Pine wood nematode, Bursaphelenchus xylophilus, causes pine wilt disease in a number of Pinus species, which is one of the most serious plant diseases in forest, Korea. In the course of a search for nematicidal substances from endophytic fungi, Fusarium oxysporum EF119 out of the 23 fungal strains tested showed the strongest activity to B. xylophilus. Two nematicidal substances were isolated and identified as bikaverin and fusaric acid. Fusaric acid showed somewhat higher nematicidal activity against B. xylophilus than bikaverin; fusaric acid and bikaverin, at $100{\mu}g/ml$, killed B. xylophilus with mortality values of 50% and 43%, respectively. In addition, both compounds acted synergistically. This is the first report on the nematicidal activity of bikaverin and fusaric acid.

• Korean journal of applied entomology
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• v.27 no.3
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• pp.159-164
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• 1988

Five nematophagous fungi were evaluated for their nematicidal effect in vitro on Rhabditis sp. and Meloidogyne hapla in soil. Inocula of Arthrobotrys arthrobotryoides, A. conoides, A. oligospora, Dactylella lobata, and Fusarium oxyaporum were grown in moistened corn-sandy soil and chopped potato-sandy soil media, and incubated at 26$^{\circ}C$ for one week. The prepared inocula were incorporated in autoclaved sandy soil, mixing thoroughly at rates equ-invalent to 1:50, 1:100, 1:200, and 1:400, repectively, before 80g of the mixture carrying 100 Rhabditis sp. was put into petri plates. Nematophagous fungi effectively teduced the popuation of Rhabditis sp. in soil in a week or two following treatment of the incula at concentration of 1:50 and 1:100. The optimum was at $25^{\circ}C$ for nematicidial effect as high as 80-100%. The at the rate of 1:100 prepared incula were incorporated in auto-claved soil, where 100 Juveniles M. hapla were introduced per 80% soil. All fungi infected the M. hapla effectively in soil, caysing more than 90% mortality within one week. This result indicated the potential value of these fungi as promising biocontrol agents.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.228-235
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• 2011

An nematophagous fungi Arthrobotrys thaumasia Nema-1 and Pseudomonas putida C-5, which degrade the collagen and gelatin, was isolated from controlled horticultural soils in Seonnam-myun, Sungju-gun, Kyungpook and Woosung-myun, Gongju-shi, Chungnam to develop biological nematode pesticide. When $5,000mL\;L^{-1}$ of A. thaumasia Nema-1 culture was treated to Meloidogyne incognita, the nematicidal activity resulted in 55% at 72 hours after treatment. While the nematicidal activity increased to 65% by treating the culture mixture of $5,000mL\;L^{-1}$ Nema-1 and P. putida C-5 after 72 hours. Furthermore, the nematicidal activity of the mixture containing cinnamon extract $50mg\;L^{-1}$, each $5,000mL\;L^{-1}$ of Nema-1 and C-5 culture was elevated to 89% at 72 hours after treatment, comparing to the result showed 17% and 57% of the nematicidal activity, respectively by the treatment of chemical nemato pesticide Fosthiazate $50mg\;L^{-1}$ and neem oil $2,000mL\;L^{-1}$. These results suggested that the mixture of microorganisms and plant extract were more effective biological nematicide than the case of only microorganism or plant extract for nematode control.

• Mycobiology
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• v.49 no.3
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• pp.294-296
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• 2021

An endolichenic fungus, Xylaria grammica strain EL000614, showed strong nematicidal effects against plant pathogenic nematode, Meloidogyne incognita by producing grammicin. We report genome assembly of X. grammica EL000614 comprised of 25 scaffolds with a total length of 54.73 Mb, N50 of 4.60 Mb, and 99.8% of BUSCO completeness. GC contents of this genome were 44.02%. Gene families associated with biosynthesis of secondary metabolites or regulatory proteins were identified out of 13,730 gene models predicted.

• Korean journal of applied entomology
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• v.32 no.4
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• pp.382-388
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• 1993

Five nematophagous fungi, Arthrobotrys arthrobotryoides, A. conoides, A. oligospora, Dactylella lobata and Fusarium oxysporum were evaluated for nematicidal effect on Meloidogyne hapla in greenhouse. Treatment of nematophagous fungi reduced the root galling by M. hapla and increased red-pepper growth in naturally infested pot soil. Number of galling were significantly less inall pots in 4 different inoculum densities of 5 nematophagous fungi compared to untreated plots. Especially, treatment of F. oxysprum resutled significant reduction of root gall of red-pepper. The increased shoot growth was significantly higher in pretreated plots by A. arthrobotryoides, A. conoides, A. oligospora, D. lobata and F. oxysporum at inoculum concentration of 1:100 but other treatments were not significantly increased shoot growth. Two promising fungi, D. lobata and F. oxysporum were selected in greenhouse test and in vitro results of previously experiment and applied to field plot naturally infested by M. hapla serverely. Number of galls were remarkably fewer in plots treated with D. lobata and F. oxysporum at either 1:70 or 1:100 concentration compared to the untreated plots. The shoot growth of red-pepper was increased strikingly in the plots following the red-pepper was increased strikingly in the plots following the treatment of both fungus than greenhouse test.

• 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 Soil Science and Fertilizer
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• v.45 no.2
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• pp.162-168
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• 2012

An nematophagous fungi Arthrobotrys thaumasia Nema-1 and Bacillus subtilis C-9, which degrade the collagen and gelatin, were isolated from horticulture plantation soil in Kyungpook Sungju-gun Seonnam-myun and Chungnam Gongju-gun Woosung-myun to develop biological nematode pesticide. When $5,000mg\;kg^{-1}$ of A. thaumasia Nema-1 nematicide powder ($7.0{\times}10^3cfu\;g^{-1}$) was treated to pot including Meloidogyne incognita, the number of nematode's egg mass, which is a index of nematicidal activity, decreased to 35% compared to control. While the number of nematode's egg mass decreased to 67% by treating the nematicide powder mixture of $5,000mg\;kg^{-1}$ Nema-1 and B. subtilis C-9 ($8.5{\times}10^5cfu\;g^{-1}$). Furthermore the number of nematode's egg mass of the mixture containing cinnamon extract $10mg\;kg^{-1}$, each $5,000mg\;kg^{-1}$ of Nema-1 and C-9 nematicide powder was decreased to 84%, comparing to the result showed the number of nematode's egg mass decreased to 24%, by the treatment of chemical nemato pesticide Fosthiazate $24mg\;kg^{-1}$. These results suggested the mixture of microorganisms and plant extract was more effective biological nematicide than the case of only microorganism or plant extract for nematode control.