• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.571-579
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• 2004

In order to obtain the genetic informations of the Korean isolates of porcine circovirus 2 (PCV2), nucleotide sequences of total genome of three isolates and open reading frame 2 (ORF2) of four isolates were determined and compared with those of other reference PCV2 isolates. Nucleotide sequences of 3 isolates showed over 99% homology with those of reference strain (GenBank accession no. AF027217). Point mutations were mainly determined on ORF2 regions but little on ORF1 regions. The patterns of pointmutated sites and nucleotide substitution on ORF2 regions were generally consistent between Korean isolates, and these mutated sites observed in Korean isolates were also relatively similar to those of foreign isolates. Phylogenetic analysis of nucleotide or amino acid sequences showed that there were minor branches consisting of three clusters; cluster of Korea, Canada and America, cluster of Spain and Taiwan, and the last cluster of French and China isolates. These results suggested that Korean PCV2s were probably originated from North America such as Canada or USA. The genetic informations obtained from this study could be useful for the research of diagnosis and pathogenecity of PCV2.

• Journal of Mushroom
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• v.6 no.1
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• pp.20-26
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• 2008

The stromatal forms of T. fuciformis and the mycelia of Hypoxylon sp. were collected. The DNA sequence in the ITS region of the 5.8S ribosomal genes of isolated strain KG103 was very similar to that of T. fuciformis AF042409 with a homology of over 98% in the EMBL/GenBank database through BLAST searching. A second isolate, No KG201, one of the symbiotic strains for cultivating T. fuciformis also exhibited high homology with Annulohhypoxylon stygium AJ390406. Potato Dextrose Medium exhibited the best mycelial growth of 14 mm/14 days and 85 mm/14 days for T. fuciformis and its symbiotic fungi, respectively. Optimum culture conditions for the micelial growth were pH 5 at $25^{\circ}C$. For the optimization of artificial cultivation of T. fuciformis in bottle with sawdust medium, several conditions such as type of sawdust, supplements, pH, moisture content, and incubation temperature were investigated. T. fuciformis and symbiotic fungi showed fast mycelial growth on corn cob media (77 and 52%) followed by oak tree sawdust and cotton seed meal. The optimal temperature for mycelial growth of T. fuciformis and symbiotic fungi on corn cob media was $25^{\circ}C$ at 55% of moisture content.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.21 no.1
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• pp.1-12
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• 2018

This study sought to analyze changes in the vegetation structure and species diversity indices in the Abies koreana forest in the Yeongsil area of Hallasan Mountain and establish basic data for Long-Term Ecological Research (LTER). The results show that the number of woody plants per 1ha has increased by 804 (45.1%) from 1,781 to 2,585 individual plants, whereas the number of live A. koreana did not change much with 796 individual plants. The number of dead tree plants, however, jumped by 807 (82.2%) from 982 to 1,789 plants. With other tree species, the number of live individual plants increased by 807 (82.2%) from 982 to 1,789 plants, whereas the number of dead plants increased by 31 from 10 to 41 individual plants. Results of the average importance index analysis show that the number of A. koreana decreased, while the number of Weigela subsessilis, Rhododendron yedoense for. poukhanense, and Magnolia sieboldii increased. The species diversity index increased by 6.7% as per the maximum level in the upper layer and by 7.2% in the lower layer, respectively. Results of the stem morphology analysis show that the number of AS type was highest with 700 individual plants among A. koreana, while their distribution by type shifted from AS>AL>DS>DB to AS>DS>AL>DB. As for other species, the AS type was most abundant with 1,580 individual plants, while their distribution by type shifted from AL>AS>AF>AB to AS>AL>AB>AD. The number of newly sprouted tree plants has increased from 420 in 2014 to 453 in 2016. Of the individual plants that were alive in 2014, 23 were found dead and 33 individual plants younger than 3 years old have been newly added to the group. The number of deaths after 2014 was highest among the 2 years olds, whereas the number of 2 years olds that sprouted in 2014 was highest among the newly sprouted tree plant group. In the A. koreana forest in Yeongsil, the density of other species was rising rapidly with the exception of the dead and live A. koreana. The occurrence of new tree plants is decreasing rapidly, thereby confirming the rapid change in the area's vegetation structure. Therefore, there is a need for continuous long-term ecological research to monitor vegetation change. It can also be used as a basic data for efficient restoration research.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.279-284
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• 1993

This experiment was conducted to investigate the seasonal fluctuation of population density and the life history of Adoxophyes sp .. Under field-cage conditions, smaller tea tortrix had 4-5 generations a year. The average periods from egg to adult emergence were 43.7 days in spring and fall, and 35.2 days in summer. The average longevity of adults was 7.0 days in spring and fall, and 6.3 days in summer. The average numbers of egg masses and eggs laid by a female were 1.8 and 40.4 m spring and fall, and 2.3 and 49.5 in summer, respectively. Population density of smaller tea tortrix estimated by sex pheromone trap and light trap showed four peaks in each late May, late June, middle August and late September. The number of individuals caught by sex pheromone trap was 2~4 times as large as that by jight trap. Smaller tea tartrix overwimered in larval stage in southern region af Korea.

• Mycobiology
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• v.35 no.2
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• pp.54-61
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• 2007

Two isolates of Tricholoma matsutake T-008 and T-034, preserved in Entomopathogenic Fungal Culture Collection (EFCC) of Korea, were used in the present study. The isolates had 100% Bootstrap homology with Tricholoma matsutake U62964 and T. matsutake AB188557 and AF309538 preserved in Gene Bank of NCBI. Mycelial growth of T. matsutake was highest in TMM and MYA at $25^{\circ}C$. The highest dry wt. of mycelium was obtained after 65 days of culture, when 6 mycelial discs were inoculated in 100 ml of broth in 250 ml shaking flask. Mycelial mats were observed in clumped condition at the inoculation sites of pine forest after two weeks of inoculation. After 5 months of inoculation, mycelia mats were observed growing inside soil and walls of a few inoculation sites, while mycelial mats growth up to $5{\sim}8$ cm were observed in the roots of pine tree after 6 months. The survival rate of the inoculum was about 40% of the total inoculation sites. The survival rate was found below 20% when the mycelium was inoculated in the summer. The reasons for low survival rates of the mycelium were mainly due to dry season and the soil-borne small animals such as earthworm and mole. After one year of inoculation, no external difference was observed between the artificially inoculated mycelia and the naturally existing mycelia of T. matsutake. The present study showed that fruiting bodies of T. matsutake could be produced by artificial inoculation under the appropriate environmental conditions.