• Korean Journal of Weed Science
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• v.8 no.1
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• pp.33-36
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• 1988

The emergences of Echinochloa glabrescens, Monochoria vaginalis, and Cyperus difformis seeds were little affected by fertilizer application. All shading treaments resulted in decrease in emergence of E. glabrescens, while shading up to 67% slightly stimulated emergence of M. vaginalis and C. difformis. The peak emergence of E. glabrescens was at two week after sowing in the full sunlight, 31, and 52% shading, but no peak emergence at the 67% shading. Emergence peaks of C. difformis were observed during 6 to 8 weeks after sowing for all shading levels employed.

• Plant Resources
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• v.1 no.1
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• pp.43-48
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• 1998

The objective of this study was to determine how elevated $CO_2$ and temperature affected early growth and competition between direct seeded rice (Oryza sativa) and a common paddy weed (Echinochloa glabrascens). By using temperature gradient chambers. Rice and E. glabrescens were grown for 5 weeks at ratios of 1:0. 3:1 and 0:1 at three temperatures ($16.4^{\circ}C,\;19.8^{\circ}C,\;and\;22.2^{\circ}C$) and either in ambient (361ppm) or elevated (566ppm) $CO_2$. For both species. elevated $CO_2$ had no effect on mainstem leaf number while air temperature had a slight positive effect which was greater in E. glabrescens than rice. With elevated $CO_2$ rice leaf area index and plant height increased alightly in all species combinations but no increases were observed for E. Glabuescens. For rice in all combinations. elevated $CO_2$ tended to increase the rot and total biomass much more than any other growth parameters: the increases in root and total biomass resulting from elevated $CO_2$ ranged from 16% to 40%. depending on air temperature. At the lowest temperature, the decrease in rice biomass in combination with E. glabrescens was significantly greater at elevated $CO_2$ (18%) than ambient $CO_2$ (3%). At the highest temperature, however, the decrease in rice biomass at elevated $CO_2$ (22%) was less than that at ambient $CO_2$ (36%). The competitive ability of rice as measured by the decrease in biomass when grown in combination with E. glabrescens depended strongly on root growth and/or allocation. These results suggest that at higher temperatures elevated $CO_2$ could enhance the competitive ability of direct seeded rice during early growth. However, at lower temperatures. the competitive ability of E. glabrescens seems to be greater.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.539-545
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• 2008

Distribution of Carex miyabei Franch., formerly considered as an endemic species of Japan, in Korea is verified and reported here. It is distinguished from the morphologically similar species in the same section, such as C. lasiocarpa Ehrh. var. occultans (Franch.) $K{\ddot{u}}k.$, C. drymopila Turcz. ex Steud. var. abbreviata ($K{\ddot{u}}k.$) Ohwi, and C. glabrescens (Kük.) Ohwi, in having long-beaked and acutely 2-toothed perigynia which are densely covered with stout short hairs.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.183-200
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• 1989

An experiment was conducted at the greenhouse of the International Rice Research Institute in 1987 to find out the character of dry matter production, the potential seed production ability and the ecological and physiological strategies to adaptation. For these, two rice cultivars, IR64(lowland rice) and UPLRi-5(upland rice), and seven weed species were used ; Echinochloa glabrescens Munro ex Hook. f., E. cress-galls ssp. hispidula (Retz.) Honda, E. colons (L.) Link, Monochoria vaginalis (Burin. f.), Ludwigia octovalvis Jacq.) Raven, Fimbristylis miliacea Vahl and Cyperus difformis L. Adaptation strategies of weed species varied by species. However, they had efficient seed production strategy through different ways. In general, sedge weed species (F. miliacea and C. difformis) produced great amount of seeds at the expense of seed size through greater ratooning ability and low relative dry weight for flowering. For broadleaved weed species, greater number of descendants were obtained through high plasticity and low relative dry weight for flowering (M. vaginalis) or greater growth ability through effective photosynthetic efficiency (L. octovalvis). Grass weed species, on the other hand, produced their seeds through effective growth (net assimilation rate and relative growth rate), high ratooning ability (except E. crus-galls ssp. hispidula) or low relative dry weight to maximum dry weight for flowering (E. glabrescens). The harvest indices of the weed species were considerably lower than those of rice. Fimbristylis miliacea had the greatest ratooning ability followed by C. difformis, E. colons and E. glabrescens. The greatest seed productivity was recorded by C. difformis (279, 000) and L. octovalvis (268,000) while rice produced the least number of seeds (1300-6100). Log seed weight had a negative linear relationship with log seed number (y=6.30-1.48X, $R=-0.965^{**}$). For all species plant plasticity response was not directly correlated with mortality response.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.3
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• pp.1-8
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• 1980

Eight different weed community types growing in association with transplanted rice were identified in the experimental fields used in these studies. The Importance Value (LV.) of weed species growing in association with rice changed with time. The I. V. of Echinochloa glabrescens Munro ex Hook f. increased from 40 days after transplanting (DAT) until heading and then, decreased from heading to maturity of rice. However, the LV. of Monochoria vaginalis (Burm.) Pres!. and Echinochloa crus-galli ssp. hispidula (Retz.) Honda increased from 40 DAT to maturity while Scirpus maritimus L. decreased from 40 DAT. There was a high negative correlation between grain yield and weed weight at rice heading in all weed communities. The competitive ability of rice against weeds varied depending upon weed species. The highest yield decrease due to weed competition was obtained from the E. crus-galli ssp. hispidula-S. Maritimus community. Forty-two percent yield reduction was caused by competition of 100g dry weight of weeds per square meter of this community type at rice heading. The yield decrease for the same amount of weeds was 10% for the E. glabrescens community, 15% for the M vaginalis community and the M vaginalis-Scirpus supinus L. community and 21% for the M vaginalis-E. glabrescens-Fimbristylis littoralis Gaud.-S. maritimus community type.

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.116-122
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• 1989

An experiment was carried out at the International Rice Research Institute in 1987 to understand the seed dormancy and germination habit of rice and several weed species. The germinability of the weed seeds just after harvest was variable depending on the species and ranged from 0 to 72%. Two rice cultivars, IR64(lowland type) and UPLRi-5(upland type) had higher than 95% in germination ability throughout the experimental period due to the fact that the rice seeds came from the harvest of the previous season and dormancy had already been overcome. The length of the storage period needed to overcome dormancy at room temperature($25{\pm}2^{\circ}C$) was about 50 days for Echinochloa glabrescens Munro ex Hook, f., more than 60 days for E. crus-galli ssp. hispidula (Retz.) Honda and 20 days for Ludwigia octovalvis(Jacq.) Raven. Seeds of E. colona(L.) Link, Monochoria vaginalis(Burm. f.) Presl, Fimbristylis miliacea(L.) Vahl and Cyperus difformis L. appeared to have no dormancy. Among the nine species M. vaginalis had the lowest germination of less than 1% throughout the experimental period. However, its seed germinated easily when planted in soil. The low germinability of E. glabrescens, E. crus-galli ssp. hispidula and L. octovalvis just after harvest could be overcome through pretreatment of seeds either by soaking in nitric acid(0.1N) for 1 day or removal of the hull in the grass species, the nitric acid treatment being superior. The results imply that germination habit of weed species varied depending on the species through their differential dormancy period or differential germination strategy.

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.108-115
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• 1989

An experiment was carried out at the International Rice Research Institute in 1987 to understand the seed germination and seedling development of rice and Echinochloa species. The percentage germination of rice cultivars(IR64 for lowland-type and UPLRi-5 for upland-type) was extremely high(>90%) regardless of temperature while that of Echinochloa species ranged from 10 to 80% depending on the species. Among these, E. crus-galli ssp. kispidula had the lowest germination with less than 20% at the high temperatures ($30^{\circ}C$, $35^{\circ}C$) and about 45% at the low temperature ($25^{\circ}C$). Original seed weight gradually decreased with time white root and shoot weight increased for both rice and Echinochloa species. However, increase in root and shoot weight did not compensate for the loss of stored carbohydrate during the experimental period. The root of E. glabrescens grew from the seed on the opposite side of the shoot while for rice it grew from the same side of the seed as the shoot. Echinochloa glabrescens had a leaf blade-like expanded first leaf that contained chlorophyll while rice had an incomplete first leaf that had no leaf blade and no chlorophyll. Due to this E. glabrescens could grow independently 2 to 3 days earlier than rice.

• Korean Journal of Food Science and Technology
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• v.39 no.5
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• pp.564-568
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• 2007

In this study, the ethanolic extracts of 40 species of traditional herbal medicines were examined for their antimicrobial activities against Clostridium difficile. Among the 43 screened traditional herbal medicines, Achyranthes Japonica Nakai (AJN), Siegesbeckia glabrescens Makino, and Phelloedendron amurense Ruprecht showed antimicrobial activities greater than 90% at a concentration of 500 ppm. According to the minimum inhibitory concentration (MIC) test the ethyl acetate soluble fraction of the AJN ethanolic extracts (AJNEA) showed the highest growth inhibitory activity against C. difficile, with a MIC of $625{\mu}g/mL$. In addition, the effect of AJNEA on the growth of lactic acid bacteria was investigated. AJNEA did not inhibit the growth of the tested Bifidobacterium spp. or Lactobacillus spp., with the exception of B. longum, Streptococcus thermophilus, and L. helveticus. These results indicate that AJNEA can be utilized as a potential antimicrobial agent against C. difficile related disease.

• Korean Journal of Plant Taxonomy
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• v.48 no.4
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• pp.331-356
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• 2018

We investigated the flora of Jogyesan Mt. and discussed important vascular plants found on this mountain. In total, 16 separate field trips (20 days overall) were completed from 2013 to 2017. There are 577 taxa on Mt. Jogyesan, consisting of 115 families, 333 genera, 520 species, 8 subspecies, 45 varieties, and 4 forms. Eighteen endemic plants of Korea were found on Jogyesan Mt., including Carex okamotoi Ohwi, Coreanomecon hylomeconoides Nakai, and Stewartia koreana Nakai ex Rehder. There are 80 taxa of floristic regional indicator plants in total, including level V such as Adenophora palustris Kom. and level IV such as Dryopteris championii (Benth.) C. Chr. ex Ching, Gastrodia elata Blume, Lindera sericea (Siebold & Zucc.) Blume and Corylopsis glabrescens var. gotoana (Makino) T. Yamanaka. There also are 24 taxa of naturalized plants, including Ambrosia artemisiifolia L.

• Korean Journal of Food Science and Technology
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• v.33 no.6
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• pp.774-783
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• 2001

The ethanol extract of 77 species of edible and medicinal plants were examined antimicrobial activity against 5 strains of Listeria monocytogenes ATCC 19111, ATCC 19112, ATCC 19113, ATCC 19114 and ATCC 15313 by optical density using Bioscreen C. The ethanol extract of Siegesbeckia glabrescens Makino, Jeffersonia dubia Benth, Aquilaria agallocha Roxburgh, Lysimachia clethroides Duby and Nardostachys chinensis Batal. exhibited comparatively strong growth inhibition effect on 5 strains of L. monocytogenes at 1000 ppm level in broth. The minimum inhibitory concentration (MIC) of ethanol extract of Lysimachia clethroides Duby was $100{\sim}500\;ppm$ on 5 strains of L. monocytogenes. The MIC of the n-hexane and chloroform fraction of the extract were same concentration as $50{\sim}100\;ppm$. The n-hexane fraction of Lysimachia clethroides Duby showed strong growth inhibition at 25 ppm on Vibrio parahaemolyticus for 72 hr at $30^{\circ}C$ and at 50 ppm on Bacillus cereus and at 500 ppm on Staphylococcus aureus and Escherichia coli.