• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.533-536
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• 2008

Hopum is a new japonica rice cultivar developed from the cross between Milyang165 and F1 crossing Milyang165 and Iksan438 at Department of Rice and Winter Cereal Crop, NICS, RDA, in 2006. This cultivar has a short grain shape and about 141 days growth duration from direct seeding to harvesting in the southern plain including Chungcheong province. This cultivar has short culm and spikelet number per panicle is similar to that of Nampyeongbyeo, while filled grain rate is lower than standard variety. This cultivar has medium size of brown rice and shows moderate resistance to leaf blast, to bacterial blight pathogens of $K_1$, $K_2$ and $K_3$ and stripe virus disease but susceptible to major virus diseases and insect pests. The milled kernel of Hopum is translucent with non-glutinous endosperm. Protein and amylose content of Hopum is about 6.5% and 18.7%, respectively. This cultivar has better palatability of cooked rice than Chucheongbyeo harvested in Gyeongki province. Its milling recovery (76.8%) and percentage of perfect-shaped milled rice (94.7%) were higher than Nampyeongbyeo. The milled rice yield of Hopum was 5.83 MT/ha (15% higher than Juan) under wet-direct seeding, 5.66 MT/ha (8% higher than Juan) under dry-direct seeding, and 6.00 MT/ha (8% higher than Nampyeong) under ordinary transplanting cultivation. "Hopum" would be adaptable for ordinary transplanting and direct seeding in the southern plain including Chungcheong province.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.1-6
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• 1977

The 'Kresek' disease in Korea caused by Xanthomonas oryzae was first found from eight counties in Jeon-nam and Kyungnam province in 1976. The study has been carried mainly on the grouping of pathogens and reproduction of the symptoms on Milyang #23, the variety had shown severe damages at the fields, by using the isolates from Hwa-sun and Kwang-san counties where the first epidemics took place. 1. The 'Kresek' disease was found mainly on Milyang #23, a new variety, at Hwa-sun, Mu-an, Kang-jin. Yung-am, Gog-sung counties in Jeon-nam province and Jin-yang county in Kyung-nam province. 2. The groups of 'Kresek' causing pathogens were the same of those producing bacterial leaf blight symptoms such as group I , II, IN and V of Xanthomonas oryzae. 3. Seventeen out of 21 isolates from Hwa-sun county where the first and severe damage found belonged to group IV, 2 to group II and 2 to group V All of 5 isolates from Kwang-san county belonged to the group IN. 4. The 'Kresek' type symptom could reproduced within 5 days after inoculation to seedlings by using root tut, spray and needle inoculation methods. j. The most of effective method for the inoculation was root cut, and then were spray and needle method. respectively. The higher concentration of inoculum produced the higher disease incidence.

• Journal of Sericultural and Entomological Science
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• v.38 no.2
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• pp.81-92
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• 1996

This study was conducted to characterize mulberry varieties by the analysis of morphological characters as well as biochemical and molecular biological markers. As for the budding stage Geumsang, Chosang i and Yeongbyeonchuwoo were early, but Dangsang 6, Hwangchuwoo were late. The lowest varietiy in rate of death atop was Dangsang 8(0.0%). Suncheonppong was the highest leaf yields in spring and autumn rearing season. In biochemical isozyme analysis, peroxidase gave good zymogram patterns in isoelectric focusing electrophoresis. There were high variations in RAPD analysis among the mulberry trees. From the obtained peroxidase and RAPD variations, cluster phylogenetic analysis was carried out using NT-SYS PC program. There were no clear grouping patterns between native varieties and leading varieties. The highest similarity was observed between Suwonsang 1 and Suwonsang 2 at about 90% similarity level.

• Korean Journal of Plant Resources
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• v.21 no.2
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• pp.162-170
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• 2008

The purpose of this study was to suggest the raw data on establishing the domestic wetland conservation plan. The results of this study were as follows. The vascular plants were summarized as 201 taxa in Ahnshim wetland; 57 families, 154 genera, 179 species and 22 varieties. The rare and endangered plant designated by Korea Forest Service was Hydorcharis dubia. In the wetland plants, the emerged plants were showed Typha angustata, Beckmannia syzigachne, Zizania latifolia, Phragmites communis, Persicaria thunbergii, Oenanthe javanica and Veronica undulata, and the submerged plants were Potamogeton crispus, Vallisneria asiatica, Hydrilla verticillata, Ceratophyllum demersum and Myriophyllum verticillatum. And the floating leaved plants were confirmed Potamogeton distinctus, Hydrocharis dubia, Nelumbo nucifera and Nymphoides peltata, and the floating plants were Salvinia natans, Spirodela polyrhiza and Lemna paucicostata. The naturalized plants were 33 taxa; Avena fatua, Dactylis glomerata, Rumex crispus, Rumex conglomeratus, Amaranthus retroflexus, Lepidium apetalum, Tlaspi arvense, Descurainia pinnata, Potentilla supina, Vicia villosa, Robinia pseruo-acacia, Amorpha fruticosa, Trifolium repens, Medicago sativa, Ailanthus altissima, Euphorbia supina, Oenothera lamarckiana, Quamoclit angulata, Ipomoea purpurea, Solanum nigrum, Veronica perisca, Helianthus tuberosus, Ambrosia artemisifolia var. elatior, Xanthium strumarium, Erigeron annuus, Erigeron canadensis, Conyza sumatrensis, Senecio vulgaris, Bidens frondosa, Tagetes minuta, Taraxacum officinale, Taraxacum laevigatum and Sonchus oleraceus.

• Applied Biological Chemistry
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• v.49 no.4
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• pp.270-275
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• 2006

[ $2{\beta},\;3{\alpha}$ ], 23-trihydroxyrus-12-ene-28-oic acid was isolated from Trapa pseudoincisa S. et Z. It has a common structure of pentacyclic triterpenes and belongs to the amyrin ursolic acid group. The cytotoxic effect of this compound was investigated in human hepatoma cell line HepG2. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid showed dose-dependent cytotoxicity in HepG2 cells. Confocal microscopy data showed that green fluorescence was increased in $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid treated-HepG2 cells in a time-dependent manner. $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid also increased the sub-G1 cell population of HepG2 cells as well as ladder-like DNA fragmentation. Taken together, our results indicate that $2{\beta},\;3{\alpha}$, 23-trihydroxyrus-12-ene-28-oic acid induced apoptosis in HepG2 cells.

• Ecology and Resilient Infrastructure
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• v.6 no.4
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• pp.267-276
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• 2019

The Gonggeomji Reservoir is a historical irrigation facility built in the 8th century and designated as a wetland protected area by Ministry of Environment, Korea. In order to collect the baseline data necessary for developing a sustainable conservation strategy, we investigated the classification of actual vegetation, the vegetation distribution and the floristic structure of the vegetation in the Gonggeomji Wetland Protection Area. In the whole protection area, a total of 26 plant communities were classified including the wetland, riparian, grassland, forest, farmland, and orchard vegetation. According to the results of detrended correspondence analysis, the structure of wetland vegetation was mainly affected by water depth and human disturbance. In reservoir wetlands, floating vegetation such as Utricularia vulgaris var. japonica, Trapa japonica, and emergent vegetation such as Nelumbo nucifera, Typha spp. completely covered the water surface. Since 2014, the reservoir wetland has been terrestrialized with the expansion of emergent and hygrophytic plants. For the sustainable conservation and restoration of wetland protected areas, it is necessary to naturalize the topography and wetland vegetation, recovery the hydrologic system, and restore ecosystem connectivity from wetlands to forests.

• Korean Journal of Heritage: History & Science
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• v.54 no.2
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• pp.98-119
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• 2021

This thesis aims to examine when the petroglyphs of Cheonjeon-ri, Ulju were carved and their nature. To achieve this, the relations between rituals and rock carving motifs are examined besides the nature of the archaeological monuments with carved petroglyphs. The investigation revealed that the figurative motifs on the petroglyphs of Cheonjeon-ri, Ulju, may have been carved during the Korean Bronze Age considering other examples of figurative petroglyphs from that period. It is reasonable to assume that the figurative animal motifs on the petroglyphs of Cheonjeon-ri, Ulju were used for rituals of fertility and rebirth as a subsistence ritual during the Korean Bronze Age. The Geomdan-ri Archaeological Culture Type is a strong candidate, having used both petroglyphs of Cheonjeon-ri and those of Bangudae, Ulju, since the Geomdan-ri Archaeological Culture Type has a higher proportion of hunting and fishing and lower proportion of rice cultivation in its subsistence than in the subsistence of the Songguk-ri Archaeological Culture Type. In contrast to the figurative motifs, the abstractive motifs, including the geometric designs on the petroglyphs of Cheonjeon-ri, Ulju, are generally accepted to have been carved during the Bronze Age. Although there have been some disputes over the symbolic meanings of concentric motifs, lozenge motifs, and other geometric motifs, they may be related to rituals for sun worship, ancestor worship, and fertility cults. Their meanings have been continuously reinterpreted.

• Research in Plant Disease
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• v.30 no.2
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• pp.148-156
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• 2024

Ralstonia pseudosolanacearum, a plant pathogenic bacterium that can survive for a long time in soil and water, causes lethal wilt in the Solanaceae family. Sigma S is a part of the RNA polymerase complex, which regulates gene expression during bacterial stress response or stationary phase. In this study, we investigated the role of sigma S in R. pseudosolanacearum under stress conditions using a rpoS-defective mutant strain of R. pseudosolanacearum and its wild-type strain. The phenotypes of rpoS-defective mutant were complemented by introducing the original rpoS gene. There were no differences observed in bacterial growth rate and exopolysaccharide production between the wild-type strain and the rpoS mutant. However, the wild-type strain responded more sensitively to nutrient deficiency compared to the mutant strain. Under the nutrient deficiency, the rpoS mutant maintained a high bacterial viability for a longer period, while the viability of the wild-type strain declined rapidly. Furthermore, a significant difference in pH was observed between the culture supernatant of the wild-type strain and the mutant strain. The pH of the culture supernatant for the wild-type strain decreased rapidly during bacterial growth, leading to medium acidification. The rapid decline in the wild-type strain's viability may be associated with medium acidification and bacterial sensitivity to acidity during transition to the stationary phase. Interestingly, the rpoS mutant strain cannot utilize acetic acid, D-alanine, D-trehalose, and L-histidine. These results suggest that sigma S of R. pseudosolanacearum regulates the production or utilization of organic acids and controls cell death during stationary phase under nutrient deficiency.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.73-82
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• 2008

The resource plants of the Mt. Geonji was listed 354 taxa; 92 families, 242 genera, 303 species, 48 varieties and 3 forms. 354 taxa listed consists of 205 taxa of edible plants(57.1%),234 taxa of medicinal plants(65.2%), 167 taxa of ornamental plants(46.5%) and 218 taxa of the others(60.7%). Specific plant species by floral region were total 22 taxa; Trapella sinensis var. antennifera in class IV, Iris ensata var. spontanea in Class II, 16 taxa(Salix glandulosa, Alnus hirsuta, Chrysosplenium flagelliferum, Mallotus japonicus, Ilex macropoda, Grewia biloba var. parviflora, Vaccinium oldhami, Lysimachia barystachys, Fraxinus mandshurica, etc.) in class I. The naturalized plants in this site were 12 families, 23 genera, 28 species, 2 varieties, 30 taxa(Bromus unioloides, Phytolacca americana, Oenothera erythrosepala, Ipomoea hederacea var. hederacea, Aster pilosus, Erechtites hieracifolia) and naturalization rate was 8.5% of all 354 taxa vascular plants. Wild plants disturbing ecosystem like Solanum carolinense and Ambrosia artemisiifolia var. elatior have been increasing. So, it needs continuing control and conservation measures on the plant ecosystem.

• The Korean Journal of Mycology
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• v.30 no.2
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• pp.157-165
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• 2002

Of 125 isolates collected from 35 golf courses, sensitivity of 44 isolates of Pythium species to metalaxyl was determined on corn meal agar with various concentrations of metalaxyl (0.1, 1.0, 10.0, 50.0, 100.0, and $250.0{\mu}g\;a.\;i/ml$). The isolates were able to be categorized into the sensitive and resistant groups based on hyphal growth measured in terms of colony diameters on the medium with $1.0\;and\;10.0{\mu}g\;a.\;i./ml$. When compared with hyphal growth on the medium without metalaxyl, hyphal growth of the sensitive group which included 31 isolates was inhibited by $66{\sim}98%$ on the medium with $1.0{\mu}g\;a.\;i./ml$, whereas that of the resistant group which included 13 isolates grew well and the hyphal growth was inhibited only by $6{\sim}26%$. When $10.0{\mu}g\;a.\;i./ml$ of metalaxyl was included in the medium, hyphal growth of the sensitive and resistant groups was inhibited by $82{\sim}99%\;and\;27{\sim}47%$, respectively. Occurrence of metalaxyl-resistant isolates of Pythium spp. not only from turfgrasses on golf courses but also from other crops was observed for the first time in Korea. Metalaxyl-resistant isolates occurred most frequently in P. graminicola. Control effects of metalaxyl were determined by applying metalaxyl after and before inoculation of 4 and 3 isolates of sensitive and resistant isolates of P. graminicola, respectively, to creeping bentgrass in pots. The minimum concentration of metalaxyl to control metalaxyl-sensitive isolates was $6.25{\mu}g\;a.\;i./ml$, whereas the disease caused by the metalaxyl-resistant isolates could not be controlled with $12.50{\mu}g\;a.\;i./ml$ of metalaxyl. The disease was controlled more effectively by an application of metalaxyl prior to inoculation than after occurrence of the disease.