• Mycobiology
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• v.35 no.4
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• pp.215-218
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• 2007

The caterpillar-shaped Chinese medicinal mushroom (DongChongXiaCao) looks like a worm in the winter and like a grass in the summer. The fruiting body has been regarded as popular folk or effective medicines used to treat human diseases such as asthma, bronchial and lung inflammation, and kidney disease. The fruiting bodies of Paecilomyces tenuipes that formed on the living silkworm (Bombyx mon) host were used in this examination. This study was carried out to investigate the proximate composition, soluble sugar, amino acid and fatty acid profiles, and contents of the bioactive ingredient including adenosine and D-mannitol in the fruiting-bodies. The moisture content was 57.56%. Soluble sugars found were glycerol, glucose, mannitol and sucrose, and the contents exceeded $24\;mgg^{-1}dry$ weight. Total free amino acid content was $17.09\;mgg^{-1}dry$ weight. Arginine, glycine, proline and tyrosine were main amino acids. The content of oleic acid in fatty acids was high. Adenosine was more abundant in fruiting bodies than corpus.

• Journal of fish pathology
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• v.25 no.2
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• pp.111-116
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• 2012

Prevalence of viral nervous necrosis (VNN) in sevenband grouper Epinephelus septemfasciatus farms was investigated during the period of 2006-2008. The outbreak of the VNN was observed from August (water temperature: $24-26^{\circ}C$) to September or October ($20-25^{\circ}C$). The viral infection resulted in acute or chronic mortality of the host, where the mortality rate of juvenile fish was higher than that of the adult fish. Phylogenetic analysis based on partial RNA2 coat protein gene nucleotide sequences revealed that all the isolates from sevenband grouper were classified into the genotype redspotted grouper nervous necrosis virus (RGNNV). In conclusion, VNN of juvenile and adult sevenband groupers during the summer season (July to October, water temperature: about $24^{\circ}C$) was caused by virus belonging to the genotype RGNNV.

• Research in Plant Disease
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• v.14 no.1
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• pp.64-67
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• 2008

In 2005 and 2007, petiole and root rot of Spathiphyllum spp. was occurred at commercial greenhouse during summer (June-September) in Koyang city and Yongin city, Kyunggi-do, Korea. The pathogenic fungus was isolated from diseased plants and the cultural and morphological chracteristic were observed. Conidia were rod in shape, 1-3 septa and $67.5-95.0{\times}4.8-6.5\;{\mu}m$ (av. $82.0{\times}6.0\;{\mu}m$) in size. The optimum temperature for the mycelial growth of the isolates was $27^{\circ}C$. According to result the pathogenicity test, first disease symptoms appeared five days after inoculation. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Cylindrocladium spathiphylli. This is the first report on Spathiphyllum spp. caused by C spathiphylli in Korea.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.677-685
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• 2020

The host rock of the Usuki Stone Buddha Statues is dark gray welded tuff involved the Aso-4 pyroclastic flow sediments. This Buddha Statues are processing chlorosis from rainfall flowing above and underground water which were urgently needed for conservation measurement. White precipitates, the main source of salt weathering, on the surface of the Buddha Statues are mainly consisted of thenardite, gypsum and dolomite. Extraction experiment result shows that thenardite was dissolved at the beginning of stirring and then redissolved after 4 hours, and gypsum was detected until stirring for 2 hours, and then dissolved after stirring for 4 hours. As a result of monitoring the microclimate environment for 11 months to determine the recrystallization environment of white precipitates, the phase transition between thenadite and mirabilite appears widely in spring, and is maintained in an aqueous solution due to high temperatures in summer and fall. In winter, mirabilite is shown the widest by decreasing temperature. Therefore we requires details monitoring for blocking water transfer port and solved humidity environment in shelter.

• Korean Journal of Environmental Biology
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• v.22
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• pp.86-92
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• 2004

The marine viral density in the Gwangyang Bay was abundant about 2.0${\times}$10$^{8}$ particles ml$^{-1}$ . For each season, viral abundances were recorded from 9.0${\times}$10$^{8}$ particles ml$^{-1}$ in summer to 0.7${\times}$10$^{6}$ particles ml$^{-1}$ in winter. The spatial distributions of the viral, bacterial and phytoplankton biomass in the Gwangyang Bay were mostly highey in closed estuarine system (Station 2, 5, 10, 12, 16, 20) than open ocean system (Station 28, 38, 42, 46, 51), And the othey closed estuarine system (Station 22, 26, 32, 34) indicated higher viral abundances, lower bacterial and plankton biomass than open oceanic system. In depths of some stations, the bacterial abundances exceeded a hundred fold than viral abundances. Seasonal abundances of marine viruses and their host systems were dynamically changed, and their seasonal variations were closely correlated. In summer, viral and bacterial abundances were increased, and phytoplankton chlorophyll $\alpha$ concentrations were maintained in average values. In winter, viral and bacterial abundances were dramatically decreased, and chlorophyll a concentrations were decreased, but, immediately increased. The viral abundances were peaked in August 2001, and bacteyial abundance, in August 2001 and June 2002, while chlorophyll a concentrations were peaked in April. 2002. In total host and viral abundances, it was seemed that their pools were maintained to steady-states by viral mortality, and viral abundance maintained steady-states. In our assessments, this report is a unique research about marine viral ecology of the Gwangyang Bay in Korea.

• Korean journal of applied entomology
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• v.33 no.2
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• pp.56-59
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• 1994

Life histoy of Nysius plebejrrs, the most injurious pest in chysanthemun cultivation in Korea, was studies both in field and inseday in Chinju during 1991 and 1992 seasons, and resulis are summarized as below 7hls insect has 3 generation per year, adult peaks on the mid April, mid June and late August, and the highest number of adults were attracted to the light tmp from the late August through mid September. Overwntered generation and needed 6-7weeks from egg rnatulity m spring, and 5-6 weeks, for both the first and second generation m summer, Incubation egg periods were 142, 9.3 and 7.2 days, nymphal penods were 45.2, 32.1 and 31.2 days, and total growth periods, were 59.4. 41 4 and 38.4 days, respect~vely for the overwintered, flst and second generation. Ovipositional penods were 25.6, 23.4 and 21.2 days. and number of eggs Iald by each female were 41.5. 37.2 and 35.4 days, respedively of each generation Longevities of female were 326, 27.5 and 25.1 days. and of male were 15 2, 12.3 and 12.1 days. respectively of each generation. Sex ratlo was about 1:1 in all generation, and eggs were laid in mass on the surface of leaves or stems of the host plants. This insed over-wmters as adult (90%) or 5th instar nymph (10%), however, over-wintering adults seem to be sexually premature, and mating take place actively in the following spring.

• YAKHAK HOEJI
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• v.30 no.5
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• pp.253-265
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• 1986

Among 230 species of herbal drugs screened, thirty one show the anthelmintic activities in vitro against Clonorchis sinensis, the chinese liver fluke. The active substances have been isolated and their structures identified. Some of the active substances and their derivatives have been synthesized, followed by anthelmintic activity tests. The extracts from the active drugs cause damages in organs of the adult worm in the hepatic duct of rabbit. Some fresh water fish, which function as bad hosts for the fluke, excrete defense substances against the cercaria of the fluke. The defense substances have been isolated from Cyprinus carpio and Cyprinus carpio nudus, followed by structural identification. The results are summarized as follows: l) The bark of Machilus thunbergii as well as the seed of Schizandra chinensis contain meso-dihydro-guaiaretic acid as the anthelmintic component. Among derivatives synthesized, 4-phenyl-1-((3, 4-dihydroxyphenyl)-, 4-phenyl-1-(3-hydroxy-4-methoxy phenyl)-and 4-phenyl-1-(4-hydroxy-3-methoxy phenyl)-2, 3-dimethyl butanes show considerable activities. Administration of the bark extract mainly damages the bladder of the adult worm. 2) The active substance from the roasted fruit of Prunus mume is 2-hydroxymethylfurfural. This substance is produced during the roasting process. Administration of the fruitextract causes a damage of the bladder of the adult worm. 3) The active substance from the root of Scutellaria baicalensis is 5.2'-dihydroxy-6, 7, 8, 6'-tetramethoxyflavone. 4) Beside alantolactone, a very strong anthelmintic component is contained in the root of Inula helenium. Administration of the root extract causes irreversible damage on the worm, affecting mainly the reproductive organs. 5) The cercaricidal substances from the epidermis of C. carpio and C. carpio nudus are ethyl linoleate and linoleic acid, respertively. 6) The cercaricidal substances from various kinds of fresh water fish have different $R_f$ values, implying that the defense substances are species-specific. Unexpectedly, the fish with good host function, for example Pseudorasbora parva, excrete the defense substances, too. The defense substances are possibly organ-specific in individual species; the organs essenstial for the existence of the species excrete the defense substances, allowing other parts to be invaded by the cercaria. 7) The cercaricidal fraction of Carassius carassius is detected only in the fish which have been collected during the summer time from May to September, Its secretion is not dependent on water temperature. Thus, it seems to be possible that the secretion of the defense substance would be stimulated through a contact between the fish and cercaria.

• Korean Journal of Ecology and Environment
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• v.38 no.3 s.113
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• pp.352-360
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• 2005

Acheilognathus signifer is distributed widely in high density in the Naechon-stream. The order of this-stream was 2 ${\sim}$ 4 and the water width is wide but the depth is relatively shallow and the sinuosity is 1.83, which indicates a meandering stream. The water width/stream width ratio is 1.59, which suggests moderate entrenchment. Naechon-stream was classed as B type by Rosgen (1995). The natural habitat of A. signifer is a slow flow velocity pool, like a backwater pool, which is made up of piled up boulders that restricts the flow of water. The stream bed is made up of boulders and sands that enable the spawning host to inhabit. A. signifer selects a microhabitat where the boulders furnish hiding places. The Habitat of A. signifer is strongly affected by the existence or not there of U. douglasiae sinuolatus. After hatching from the mussel, A. signifer inhabits the surface of the water. It then moves to the low layer once it acquires swimming ability. While A. signifer inhabits the river in summer, A. signifer moves to the deeper layers in winter, where there are the refuge like rocks and boulders. In spring A. signifer moves from the deep water to the river line where the mussels reside.

• Asian Journal of Turfgrass Science
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• v.19 no.2
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• pp.85-94
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• 2005

A fungal isolate was newly collected from Zoysiagrass 'Anyang-Joongji' in small circular patches on a fairway ofa golf course in Korea, which seriously occurred during the early summer period of 2005. The isolate presented on PDAmedium, named Scz1, was closely identical to Sclerotinia homoeocarpa, a casual fungus of dollar spot disease, in cool season turf grasses such as creeping bentgrass. Hereby, this study was accomplished to characterize the isolate and compare it with the fungus, named Scb1, isolated from dollar spot-infected creeping bentgrass (Agrostis palustris Huds. cv Penncross). On PDAmedium, individual mycelial appearance of three isolates was very similar except for the pigment. Mycelial pigments of Scz1 and Scz2 (another analogous isolate collected) were light pinkish on the reverse side of PDA medium but that of Scb1 was dark brownish. In a microscopic study, three isolates were barely distinguishable in the appearance of mycelia. As expected, in the temperaturesensitivity assay, all pathogens were very delicate to $32^{circ}C$ above but not to $30^{circ}C$ below, in which was explained to be one of typical characteristics in S. homoeocarpa. In an artificial inoculation assay, disease symptoms including leaf spots in Zoysiagrass were appeared within 6-7 days after inoculation through the hand inoculation method with the isolate-infested soil. Then the fungus was re-identified from the infected leaf tissues. Interestingly, inoculation of isolate Scz1 gave rise to distinct symptoms in only Zoysiagrass but not in creeping bentgrass 'Penncross' and Kentucky bluegrass 'Midnight'. The observation might be involved in host specific pathogenecity of S. homoeocarpa Scz1 to Zoysiagrass. In a chemical sensitivity assay for the isolate, Scz1, showed a high mycelial inhibition against two fungicides, iprodione and propiconazole. All results described above suggest that S. homoeocarpa Scz1 is a primary pathogen of Zoysia dollar spot disease.

• Korean Journal of Ecology and Environment
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• v.33 no.2 s.90
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• pp.128-135
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• 2000

The authors surveyed the seasonal variations of environmental factors, the distributions of heterotrophic bacteria and Anabaena cylindrica growth-inhibiting bacteria at each water layer in Daechung Reservoir to verify the role of bacteria during the extinction of bloom. Average water depth at site 1, 2, and 3 were 25.5 m, 15.0 m and 12.3 m, respectively. Water temperature showed a typical pattern seasonally. The variation of DO was relatively inverse proportional to that of water temperature, although it was irregular during summer time. DO decreased gradually to early May, fluctuated sharply after then, and followed by gradual increasement after middle of September. This variation pattern was notable at surface layer. There was remarkable difference in DO concentraion between surface layer and the other water layers during the period in which DO irregulary varied. The variation range of chlorophyll-a concentraion at surface layer in summer time was broad, and it was relatively high when DO was high. The population size of heterotrophic bacteria was high from Spring to Autumn, an declined after September when the water temperature droped rapidly. Especially this variation pattern was prominent at the surface layer. Bacteria that inhibit the growth of A. cylindrica was almost not detected by June, and its distribution increased in July. Afterward, it showed different variation pattern between each site. The distribution of A. cylindrica growth-inhibiting bacteria was higher at the middle and bottom layer than the surface layer in July and October, when it was larger at all sites for the study period. This result suggests that the antagonistic bacteria exhibit higher activity when host activity drops. These results also suggest that natural water bacteria control the distirbution of cyanobacteria, especially its activity as controller is remarkable when cyanobacterial growth declines.