• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.717-720
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• 1998

Some physico-chemical components of Chinese water chestnut were analysed to provide fundamental data for water chestnut processing and products development. The contents of moisture, crude protein, crude lipid, crude ash, crude fiber and carbohydrate of Chinese water chestnut were 79.40%, 1.74%, 0.06%, 1.10%, 0.60% and 17.71% respectively. Free sugars identified in Chinese water chestnut juice were sucrose 8.58%, glucose 1.64% and fructose 1.58% as major component and maltose as trace component. The proportion of major free sugars to total soluble solid content of juice was about 66.0%. Potassium content in Chinese water chestnut was 408.57 mg% as major mineral, iron and manganese content were 0.21 mg% and 0.08 mg% as minor mineral. $Vitamin\;B_1$ and C content were $31.2\;{\mu}g/100\;g$ and trace respectively. Organoleptic properties of Chinese water chestnut were fresh fruit odor and sweet taste as main flavor. Though water chestnut was boiled for 20 min, crunchy texture of flesh was almost maintained.

• The Korean Journal of Ecology
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• v.28 no.2
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• pp.85-92
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• 2005

This study emphasizes syntaxonomy and syndynamics of intermediate (Zwischen) moor (area: 14,000 $m^2$) at Mt. Shinbul in Yangsan, southeastern Korean Peninsula. A total of 105 vascular plant species including 26 monitor-species were recorded. Analysis by the $Z\"{u}rich$-Montpellier School's method distinguished eight vegetation units: Eleocharitis-Blyxetum echinospermae ass. nov., Eriocaulon sikokianum-Utricularia racemosa community, Eleocharis wichurai-Molinia japonica community, Platanthero-Molinietum japonicas, Miscanthus sinensis for. purpurascens community, Tripterygium regelii community, Symplocos chinensis-Quercus mongolica community, Symplocos chinensis-Quercus dentata community. PCoA (Principal Coordinates Analysis) shows that vegetation changes and distributional aspects are associated with both moisture condition and sunlight on the ground layer and soil nutrient level (mesotrophic to oligotrophic). Most important to Molinietea japonicas being representative intermediate moor vegetation at the southeasternmost fringe of the Korean Peninsula is the local cooling effect by mountainous cloud and mist zone resulting in shorter and wetter growing season. The Yangsan moor vegetation was compared with earlier descriptions of related Mujechi moor from anthropogenic and natural moor vegetations.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.21 no.1
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• pp.24-34
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• 1976

The most troublesome perennials in the paddy fields in Korea, such as Cyperus serotinus, Potamogeton Franchetii, Sagittaria pygmaea and Eleocharis Kuroguwai, were studied about shape, aspects of ,germination, depth of development(under flooded and upland conditions), reproduction process and production amount. And these characters were compared with in these perennials.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.14-18
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• 1985

This experiment was conducted to characterize the weed flora in protected semi-irrigated rice seedbeds. There are 22 species in 16 genera and 12 families, consisting of 13 annual and 9 perennial weeds in protected semi-irrigated rice seedbed in Jeonbug province. The highest frequency was obtained with Echinochloa crusgalli(L.) Beauv., Cyperus difformis L., Eleocharis acicularis Rome et Schult, and Monochoria vaginalis Presl. Sites showing Simpson's index ranging from 0.1 to 0.5 reached 82% and 89% of all sites studied in 1983 and 1984, respectively. Dominant weed species were E. crus-galli and C. difformis in both years studied and the community dominance has changed from 0.67 in 1983 to 0.61 in 1984.

• Journal of Life Science
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• v.26 no.7
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• pp.782-788
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• 2016

To check the possibility of using natural extracts for cosmetic substances, we tested the bioactive effects of 11 crude extracts originating from native plants grown in the Republic of Korea on anti-oxidant and anti-wrinkle activities. When DPPH scavenging activities were measured, the crude extracts of Vitex rotundifolia, Scirpus triangulatus, S. wichurae, S. tabernaemontani, and Aeschynomene indica assays had more than 70% of DPPH scavenging activities at 100 μg/ml concentration. The data from the hydrogen peroxide scavenging assay revealed that the crude extracts from the 10 species, except for Eleocharis mamillata var. cyclocarpa, could scavenge more than 90% at 1,000 μg/ml concentration. The crude extract of V. rotundifolia had the highest xanthine oxidase scavenging activity at a 1,000 μg/ml concentration. Based on the four anti-oxidant assays, the crude extracts of V. rotundifolia, S. triangulatus, S. wichurae, S. tabernaemontani, and A. indica were shown to have excellent anti-oxidant capacities overall. In addition to the anti-oxidant capacities, the crude extract from S. wichurae exhibited high collagenase inhibitory activity, therefore, it could be a promising candidate for a cosmetic ingredient with anti-oxidant and anti-wrinkle qualities. The results of this study indicate that many wild plants native to the Korea Peninsula can be used as excellent natural substances for cosmetics based on their bioactive effects.

• Korean Journal of Weed Science
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• v.12 no.4
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• pp.317-334
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• 1992

Weed flora and floristic composition were reviewed in lowland rice field and upland crop area. For lowland rice field weed flora was not much changed since 1971. About 29 weed species belonged to 18 families were occurred. However, floristic composition of dominant weed species has greatly changed mainly due to introduction of herbicides. The predominant weed species in 1971 when herbicide was not used were Rotala indica, Eleocharis acicularis, Monochoria vaginalis, Echinochloa crus-galli, while these for in 1991 were Eleocharis kuroguwai, Sagittaria pygmaea, S. trifolia, Echinochloa crus-galli and M, vaginalis, respectively. In 1981 weed survey, E. crus-galli was no longer troblesome weed. However, this species became important again thereafter by introduction of herbicide mixtures with pyrazolate, bensulfuron-methyl or pyrazosulfuronethyl. For upland crop area, 216 weed species belonged to 46 families were recorded. One hundred and sixtyfive of these were grown in winter crop area while 189 weed species occurred in summer crop area, respectively. Among these, 138 weed species were grown in both crop seasons. In general, summer crops had less number of weed species compared to winter crops. Even though the dominant weed species varied by crop the most common weeds were Chenopodium album, Alopecunrs aqualis, Stellaria alsine and S, media for winter crops and Digitaria sanguinalis, Portulaca oleracea, Chenopodium album and Acalypha australis for summer crops, respectively.

• Korean Journal of Weed Science
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• v.18 no.3
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• pp.179-185
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• 1998

This study was conducted to investigate changes in weed occurrence and dominance as affected by seeding dates in water seeded rice paddy under field following two years of no-tillage condition. The pre-emergence weeds in no-tillage paddy were controlled by glyphosate application at 7 days before seeding. The rice seeds were seeded on April 20, May 10 and May 30, respectively with 40kg/ha of seeding rate. The weed species in the paddy occurred included three species (Echinochloa cursgalli, Aneilma keisak, Ottelia alismoides) of annual weed, one species (Alopecurus aequalis) of biennial weed and five species (Eleocharis kuroguwai, Leersia japonica, Sagittaria pygmaea, Sagittaria trifolia, Potamogeton distinctus) of perennial weed respectively. Aneilma keisak was found to be dorminant on April 20 and May 10 but Eleocharis kuroguwai on May 30 based on number of weeds. The number and dry weight of weeds occurred were higher on May 10 as compared to in other seeding dates, while proportion of perennial weeds increased as the seeding date was delayed. In particular, weed dorminance varied marketly with seeding date. The Simpson's indices were 0.736 on April 20, 0.261 on May 10 and 0.281 on May 30, respectively.

• Korean Journal of Plant Taxonomy
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• v.45 no.1
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• pp.96-107
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• 2015

This study presents a comprehensive account of the flora of hydrophytes and hygrophytes on Jeju Island. This approach aims to contribute to fundamental information about the conservation of plant diversity in wetlands. Field surveys were carried out from May of 2010 to September of 2014 in various types of wetlands on Jeju Island. A total of 189 taxa, including 52 families, 98 genera, 181 species, 6 varieties, 2 forma and 189 taxa, were found. Among them, 99 taxa (38 families, 60 genera, 96 species and 3 varieties) were hydrophytes and 90 taxa (23 families, 45 genera, 85 species, 3 varieties and 2 forma) were hygrophytes. In addition, Eleocharis${\times}$yezoensis H. Hara (Cyperaceae) was newly added to the flora of Korea. The protected wild plants designated by the Ministry of the Environment were 5 taxa, including Brasenia schreberi J. F. Gmel. and Dysophylla yatabeana Makino. The endangered species found included one Critically Endangered Species (i.e., Mankyua chejuense B.-Y. Sun, M. H. Kim & C. H. Kim), 5 Endangered Species (e.g., Lysimachia leucantha Miq.) and 7 Vulnerable Species (e.g., Tillaea aquatica L.). The floristic regional indicator plants found in this area were 44 taxa comprising 10 taxa of grade V, 7 taxa grade IV, 15 taxa of grade III, 5 taxa of grade II, and 7 taxa of grade I. The identified naturalized plants were 10 taxa; 8 families, 8 genera, 9 species and 1 variety. In the wetlands on Jeju Island, high plant species diversity was shown, and a number of rare plants and phytogeographically important plants were found. For these reasons, we consider that the wetlands on Jeju Island are very important areas from a botanical point of view. It is necessary to establish specific protection and maintenance policies in an effort to conserve these wetlands and species.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.264-281
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• 1996

As a consequence of wide use of herbicides, Eleocharis kuroguwai Ohwi became a dorminant problem weed for rice cultivation in Korea. To understand the establishment of the weed, experiments on physio-ecological characteristics were carried out sprouting and occurrence, the results could be summarized as follows: Sprouting percentage remained 68 to 73% until the time of field emergence, indicating many of the them are still dormant. The proportion of the dormant tubers were greater for the smaller than the bigger tubers. Apical dominance was apparent in sprouting, with 84% of tuber sprouted from only one of the apical buds. Tubers sprouted from 2 or 3 buds were less than 20%, and were mostly from the bigger tubers. When the shoot growth was compared, by controlling the others, ones from apical and the next 3 buds showed similar vigorous growth, but the later ones showed poorer growth. For the longevity of tubers, deep soil storage appeared to be better than storage in temperature controlled room to 2~$3^{\circ}C$. Emergence of E. kuroguwai was better in clay soil than in sand, and the possible depth for emergence in clay soil appeared to be up to 21cm, but was 15cm in sand. When tubers were exposed to salt solutions before emergence tests, E. kuroguwai appeared to be much sensitive to salts than S.planiculmis. Among the tubers formed in previous year, 12.7% remained still viable until the end of next crop season, but with relatively strong dormancy. The first emergence was about 10 days after planting at ordinary cropping seasons, and the days to the maximum shoot number stage were 60~90 from planting. The duration was extended at early transplanting, and shoot number, leaves per shoot, and tubers developed per plant were also greater at early plantings. The 6th order offshoots were developing when E. kuroguwai was planted at early season. When planted at later seasons, generation and the number of offshoots was reduced planted at early season. When planted at later seasons, generation and the number of offshoots was reduced and the number of tubers, runner and rhizome lengths was also reduced.

• Weed & Turfgrass Science
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• v.3 no.4
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• pp.312-317
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• 2014

This study was conducted to obtain basis information for effective weed control by the fact-finding survey of herbicides use at farmer's level and distribution of herbicide resistant weeds in paddy field of Jeonbuk province, Korea. The distributions of major paddy field weeds and frequently used herbicide according to the survey were as follows. The dominant weeds in rice paddy field were Echinochloa crus-galli, Eleocharis kuroguwai, Scirpus juncoides, Monochoria vaginalis, etc.. Preferred herbicides widely used by farmers were ranked in the following order, early and middle treatment (48.0%), treatment before transplanting (36.7%) and foliar treatment (15.3%). The occurrence of herbicide-resistant weeds according to collected paddy soils was as follows. The occurring area of herbicide-resistant weeds was 24,413 ha, approximately 18.4% of rice cultivation area. Herbicide-resistant weeds were occurred in four species. The order of occurrence were Scirpus juncoides (39.0%) > Monochoria vaginalis (27.8%) > Echinochloa crus-galli (16.6%) and Cyperus difformis (16.6%). This information could be useful for estimation of future herbicide-resistant weed and establishment of herbicide-resistant weed control methods in Jeonbuk province, Korea.