• Journal of Ginseng Research
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• v.28 no.4
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• pp.183-190
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• 2004

On May of 2002, the 34 isolates of Rhizoctonia solani were isolated from the symptom of damping-off on basal stems of 2-year-old to 6-year-old Panax ginseng which were cultivated in the 17 fields in Kyunggi-do, Chun­gcheungnam-do and Jeollabuk-do province in Korea. All isolates were identified as anastomosis group 2-1. Pre-emer­gence damping-off occurred on underground part of stem of 2-year-old ginseng in the pot trial with artificial inoculation. However, in the 4-year-old ginseng field with artificial inoculation, post-emergence damping-off occurred. The severe incidence of damping-off was found in the 6-year-old ginseng field in Kimje-si, Jeollabuk-do province on June 5 of 2003, the rate of which showed $18.6{\%}$ of area in the field by spread of the disease since 2-year-old. The sclerotia of R. solani, started to be formed after 7 days incubation on potato dextrose agar at $25^{\circ}C,$ were grayish brown, spherical to irregular and about $500{\mu}m$ in diameter, which became dark brown after 14 days incubation. The temperature range for the myce­lial growth of R. solani isolates was $5\~30^{\circ}C,$ and the optimal temperature was $25^{\circ}C,$ their growth were very poor at $5\;or\;30^{\circ}C$. The isolates grew at the range of pH $4.5\~8.1$ tested and optimal pH for growth was pH 4.5$\~5.8%, whereas their growth were very poor above the pH 7.2.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• Korean Journal of Environment and Ecology
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• v.23 no.2
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• pp.116-126
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• 2009

This study was carried out focused an ecological characteristics and habitat management of Abeliophyllum distichum subpopulations in the Byeonsanbando National Park, Korea. Among three subpopulations of the target species in the studied area, Gamaso region are known as translocation site due to the dam construction while the wild populations which is located at both the lower terrain of the Buandaem bank and Chongnim-ni, which is designated as Natural Monument No 370, is threat due to an intensive site management likes clearance of scrub amongst the Abeliophyllum plants. Vascular plant taxa in the studied sites were summarized as 182 taxa; 65 families, 143 genera, 164 species, 17 varieties and 1 form, and Gamaso area, the lower terrain of the Buandaem and Cheongnim-ni areas are summarized as 75, 102 and 89 taxa, respectively. The plant species likes persimmon tree, paulownia tree and wild mulberry tree are dominant species in the Gamaso subpopulation, while Quercus variabilis is dominant at the lower terrain of the Buandaem. The intensive site management was applied to the Cheongnim-ni subpopulation, one of the original wild habitats of the species. The population dymanics was varied; the one or two sprouting number of stems was over 87% both at Gamaso area and the lower terrain of the Buandam, while the Cheongnim-ni subpopulation recorded as 74.8%. Also three sprouting number recorded as 16% and as 9.2% for sprouting on numbers of four to eleven. The invaded species likes Chenopodium album, Rumex obtusifolius, Phytolacca americana, Pharbitis nil, Solanum lyratum, Erigeron canadensis and Erigeron annuus, were found at the wild habitat of the species, and those invaded species grow faster than Abeliophyllum plants. Among three habitats of the target species in the studied area, the habitat which in located at the lower terrain of the Buandam and Gamaso region are known as translocated due to the dam construction, and wild subpopulation at Chongnim-ni, which is designated as Natural Monument No 370, is under threatened due to an intensive site management likes clearance of scrub amongst the Abeliophyllumplants. It is one of the evidence that Cuscuta japonica at the population indicated an intensive site management likes clearance of scrub is not proper habitat management protocol. Thus, further researches should be followed to determine the effect of canopy removal and other disturbance factors as management techniques.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.91-102
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• 1985

Growth and biomass production of natural stands of Quercus variabilis in relation to tree density were studied to obtain basic guide lines for future tending operation. Two natural stands of Quercus variabilis located at 900m (A stand: 6,600trees/ha, $15.84m^2/ha$, $\frac{19}{17-20}$) and 800m (B stand: 4,300trees/ha, $16.65m^2/ha$, $\frac{20}{17-21}$) elevation in Sancheong, Kyongnam Province were selected for the comparative study and following results were obtained through a sample plot method. After diameter of individual trees in the sample plots was measured, twelve average trees from each diameter class were cut felled to measure dry weight of $W_S$, $W_B$, $W_L$, $W_{Ba}$, and standing biomass and biomass production rates by a allometrior regressions related to $D^2H$. Vertical distribution of leaves along the stems indicated that photosynthesis was carried out 2.2m above the ground in Stand A and 1.2m in Stand B. Maximum photosynthesis was located 4.2m and 6.2m above the ground in Stand A and B, respectively. Leaf area index was 4.25ha/ha for Stand A, and 3.89ha/ha for Stand B. Above-ground standing biomass was 49.51 ton/ha for Stand A and 59.20 ton/ha and net annual production was 6.75 ton/ha/yr. for Stand A and 8.99 ton/ha/yr. for Stand B. The ratio of net annual production to standing biomass was 17.5% for Stand A and 16.7% for Stand B. Net assimilation rate was 2.75kg/kg/yr. for Stand A and 3.58kg/kg/yr. for Stand B. Stem wood production rate was 1.46kg/kg/yr. for Stand A and 2.09kg/kg/yr. for Stand B. Bark production rate was 0.60 kg/kg/yr. for Stand A and 0.34kg/kg/yr. for Stand B. Above data indicated that Stand B utilized growing spaces and sites more efficiently than Stand A. It is concluded chat productivity of natural stands of Quercus variabilis can be enhanced through optimization of basal areas and number of tree per hectare and that sound management of natural oak stands should be based on systematic sampling of the area for periodic productivity estimation.

• Journal of Korean Society of Forest Science
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• v.49 no.1
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• pp.11-31
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• 1980

The morphological, anatomical and physiological traits were eximined for Populus alba ${\times}$ glandulosa which is an important planting species in Korea. The results obtained are as follows: 1. External characters in the leaf shape and chaff shape in the catkin were inherited as incomplete dominance but nectar gland was inherited as dominance. 2. Among the 15 selected clones, 9 clones were male, 2 clones female and 2 clones monoecious. 3. There were well-developed cork layers and bast fiber bundles in the bark. 4. Primordial leaves composed of 3 layers of cells and those undifferentiated into palisade and spongy parenchymas differed in its origin. 5. Leaf scare consisted of two kinds of tissues; one is connected to vascular bundle and the other not to vascular bundle. Tissues which had been connected to vascular bundle were isolated with only 2 or 3 layers of cork cells from the outside. 6. There was complicated arrangement in the vascular bundle of petioles. 7. Growth of the hybrid was sensitively influenced by external temperature, day-length and amount of light. In particular, it was apparent in height growth. 8. Flatness, loam soils and a $60{\times}60cm$ spacing might be best factors for the growth of P. alba ${\times}$ glandulosa. 9. The rooting of 15 clones was dependant upon external factors. 10. The growth of P. alba ${\times}$ glandulosa was best at around 80% of soil moisture content on the basis of plot water capacity. 11. Temperature difference between inside and outside stems below 100cm during the winter was the greatest at the south among seasons and among directions. 12. The sap movement was markedly influenced by air temperature, relative humidity in forest stand and moisture content in stem. 13. Total sugars in the cortex changed with season but did not differ in the dircetion of the stem. 14. Isoperoxidase variations in the leaf were different among 15 clones. Thus, it may be useful as a criterium for clonal identification. 15. The rate of soil moisture content decreased at a rapid slope was faster than that at a slow slope. Poor growth of P. alba ${\times}$ glandulosa at the slope was probably due to depletion of soil moisture.

• Journal of Life Science
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• v.27 no.6
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• pp.640-645
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• 2017

Clerodendrum trichotomum (CT) leaves and stems have been used in folk medicine for their anti-hypertension, arthritis, rheumatism, and anti-inflammatory properties. This study was performed to evaluate the potential of CT as an anti-oxidant and anti-inflammatory agent. CT leaves were extracted using 70% ethanol (EtOH). Then, using this extract, a hexane, chloroform ($CHCl_3$), ethyl acetate (EtOAc), and n-butanol (BuOH) fraction was prepared. The polyphenol contents were higher in the EtOAc fraction ($78.08{\mu}g/mg$) and BuOH fraction ($77.54{\mu}g/mg$) compared to the other fractions. Also, these two fractions exhibited strong 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities. Xanthine oxidase inhibitory activities were higher in the $CHCl_3$ fraction ($IC_{50}=4.43{\mu}g/ml$) and EtOAc fraction ($IC_{50}=5.69{\mu}g/ml$). Moreover, the EtOAc fraction effectively inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells ($IC_{50}=18.87{\mu}g/ml$). Thus, we investigated the effects of the EtOAc fraction on the expression of pro-inflammatory cytokines, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 cells. The treatment of the EtOAc fraction ($100{\mu}g/ml$) effectively decreased the levels of the tumor necrosis factor ${\alpha}$ ($TNF-{\alpha}$) and interleukin-6 (IL-6), and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). These results suggest the potential for CT extract and fractions as promising anti-oxidant and anti-inflammatory agents.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.108-119
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• 1996

Several parameters of hydraulic architecture relating to hydraulic conductance in xylem vessels were investigated in the current-year shoots of six species of deciduous oak trees. The above parameters were also investigated in the sprouts of Quercus mongolica and Q. variabilis, as well as in the seedlings of Q. mongolica and Q. acutissima. The values of specific conductivity, leaf specific conductivity and Hagen-Poiseuille's relative hydraulic conductivity relating to vessel diameter of Q. dentata were the highest in all of the species studied. The above values of most of the species studied were higher in May-June than in September-October because of increasing the vessel embolism by cavitation and so on through the growing season. The estimated values of relative hydraulic conductivity of vessel by Hagen-Poiseuille's empirical equation and the real values of hydraulic conductivity presented positive relationships in most of the species studied. Huber value and leaf specific conductity using leaf area or leaf weight generally exhibited similar patterns each other even if having some exceptions. The hydraulic conductances of sprouting shoots were much better than those of normal growing shoots in Q. rnongolica and Q. variabilis. The specific conductivity and leaf specific conductivity were rapidly decreased by the vessel embolism through cavitating just after cutting the shoots in Q. mongolica and Q. acutissima seedlings. Diurnal changes of the conductivities in the seedlings of Q. mongolica and Q. acutissima presented the possibility of their self-controlling of conductance by active moisture absorption under mild water stress. Specific conductivity and leaf specific conductivity, and so on of Q. acutissima seedlings subjected to periodical moisture stress or not have decreased through the growing season, but the influences of moisture stress to the conductance were not proved definitely because of influencing similarly and simultaneously to the development of xylem and leaf having inverse relation in the influences. The values of conductivities were higher generally in middle or upper parts of stems than root collar in the seedlings.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.218-222
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• 2006

This experiment was conducted to investigate the effects of climatic factors varied due to the type of plastic house, cultural season and location in the house on the growth of cucumber plants grown by nutrient solution. There were two growing periods, summer culture and retarding culture, two types of plastic houses, 1-2W type house and post-less house. Air temperature, relative humidity and amount of solar radiation in the plastic houses were measured. Also, dry weight of leaves and stems, plant height, number of leaves per plant, leaf area per plant and fresh weight of fruits per plant were observed. Plant growth analysis were conducted and interrelationships between climatic factors and physiological characteristics were investigated. The results were as follows. There were no differences between the type of plastic houses in the average air temperature and average relative humidity in the plastic house, but amount of solar radiation in 1-2W type house was significantly higher than that of postless house. Daily cumulative solar radiation were highest in southwest side of 1-2W type house and northwest side of postless house. Plant height and number of leaves per plant were higher in summer culture than retarding culture, while leaf area per plant was higher in retarding culture than summer culture. Relative growth rate (RGR) showed highly significantly positive correlations with net assimilation rate (WAR) and leaf area ratio (LAR). Contribution of NAR to RGR was much higher than that of LAR. Crop growth rate (CGR) showed highly significantly positive correlations with leaf area index (LAI). It appeared that increase of LAI was important to increase productivity of cucumber. Average daily air temperature for the whole growing period showed highly significantly positive correlations with RGR and NAR. Furthermore, cumulative solar radiation for the whole growing period in retarded culture showed significantly positive correlation with RGR and NAR.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.466-477
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• 2018

In this study, the anti-inflammatory activities of the extracts of different parts of Hovenia dulcis such as leaves, stems, and roots were investigated. Among them, the roots extract (RE) showed the most potent suppressive effect against pro-inflammatory mediators in LPS-stimulated mouse macrophage cells. RE induced dose-dependent reduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and concomitantly reduced the production of NO and $PGE_2$. Additionally, pre-treatment with RE significantly suppressed the production of inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), interleukin $(IL)-1{\beta}$, and IL-6, as well as mRNA levels. Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-kB) were also strongly attenuated by RE in RAW264.7 cell. Furthermore, RE induced HO-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and increase HO-1 activity in RAW264.7 macrophages. Therefore, these results indicate that RE strongly inhibits LPS-induced inflammatory responses by blocking NF-kB activation, inhibiting MAPKs phosphorylation, and enhancing HO-1 expression in macrophages, suggesting that RE of H. dulicis and a major component, 27-O-protocatechuoylbetulinic acid could be applied as a valuable natural anti-inflammatory material.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.4
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• pp.363-372
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• 2019

The leaves and stems of Centella asiatica have a long history of their usage as a medicine for the treatment of skin diseases such as ulcers and psoriasis, especially in Asia. Triterpenoids, the active components of Centella asiatica including asiaticoside, madecasosside, asiatic acid and madecassic acid, have shown to inhibit skin inflammation as well as improve skin photoaging. The main objective of this study is to investigate whether the Centella asiatica ripened with lava seawater which is rich in minerals known to be beneficial to human body can provide anti-inflammatory and moisturizing effects to skin. HPLC analysis showed that the concentration of triterpenoids increased further after ripening Centella asiatica with lava seawater. In order to confirm the inflammatory efficacy of the extract of the extract of the ripened Centella asiatica, the production of NO in LPS-activated RAW 264.7 cells and the expression of inflammatory cytokines in PM10 or UVB-induced HaCaT cells were observed. We found that the extract of the ripened Centella asiatica inhibited the expression of NO, IL-6, IL-8, and TNF-a and had higher inhibitory effect compared to the extract of the non-ripened Centella asiatica. In order to confirm the skin moisturizing effect, we investigated the synthesis of HA in HaCaT cells. The result showed HA production was enhanced in a concentration-dependent manner from the ripened group, while there was no efficacy from the non-ripened group. Taken together, it is concluded that the extract of the Centella asiatica ripened with lava seawater was effective in anti-inflammation and moisturization.