• Title/Summary/Keyword: sedges

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A Study of Epidermal Patterns of the Leaf Blades on Korean Sedges, Eriophorum, Fuirena, Kobresia, Rhynchospora and Scirpus(6) (한국산 사초과 식물 잎의 표피형에 대하여(6))

  • 오용자
    • Journal of Plant Biology
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    • v.17 no.2
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    • pp.99-105
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    • 1974
  • Author has studied and reported on taxonomy of Korean sedges, using gross morphology, anatomy and epidermal patterns of the leaf blades(1969, 1971, 1973, 1974). This paper is the 6th report of epidermal patterns of leaf blade on sedges and includes 5 genera, Eriophorum, Fuirena, Kobresia, Rhynchospora and Scirpus. The author proposed to find epidermal patterns of leaf blades as an important taxonomic characteristic of sedges classification. The result of this study, the elements of leaf epidermis, subsidal cells, silica body, cell wall of long cell, prickles, and arrangement of the elements are considered to be significant characteristics for the identification and classification of sedge.

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Statuses and Perspectives of Herbicides Development Against Herbicide-Resistant Weeds in Paddy Field of Korea (논 제초제 저항성 잡초 발생에 따른 제초제 개발 현황과 방향)

  • Park, Tae-Seon
    • The Korean Journal of Pesticide Science
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    • v.12 no.1
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    • pp.1-8
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    • 2008
  • The widespread and diverse sulfonylurea (SU) resistance problem has found in Korea, where one-shot-treatment herbicides such as pylazosulfuron/molinate and bensulfuron/molinate have been used continuously since 1989. The SU-resistant weeds of 7 annual weeds and 3 perennial weeds as of 2008 have confirmed in paddy fields in Korea. An effective management to SU-resistant weeds requires an integrated approach toward the weed control system, in particular, as to the drastic changes of herbicides development. Recent trend of new paddy herbicides in Japan has been developing to maximize the management of SU-resistant weeds. In the future, it is expected that the development of paddy herbicides in Korea is likely to be shifted toward the new "one-shot-treatment" included with herbicides of over 3-ways to maximize the control of resistant weeds. Bromobutide and carfentrazone are effective against sedges and broad-leaved weeds, respectively, and benzobicyclone and pyrimisulfam are effective against sedges and broad-leaved weeds.

Evaluation of Carfentrazone-ethyl Alone and in Combination with Glyphosate or Glufosinate for Weed Control in Orchards (Carfentrazone-ethyl의 단제와 Glyphosate 및 Glufosinate와의 혼합처리에 의한 과수원에서의 잡초방제효과)

  • Lee, H.J.;Han, S.U.;Guh, J.O.;Kim, M.H.
    • Korean Journal of Weed Science
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    • v.17 no.3
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    • pp.256-261
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    • 1997
  • Effect of a new postemergence herbicide carfentrazone-ethyl on controlling weeds in pear orchards was examined and compared with that of glyphosate and glufosinate. Herbicides tested were applied in mid June when weeds had reached at an average height of 15 to 20cm. The experimented orchards were infested mainly by dicots of Artemisia princeps, Chenopodium album, Polygonum hydropiper, Erigeron canadensis, Commelina cummunis, Calystegia japonica, and Amaranthus ascenders, and monocots of Echinochlor crus-galli, Digitaria sangunalis, Setaria viridis, and several sedges, Carfentrazone-ethyl alone effectively controlled dicot weeds in the orchards, but not monocot weeds. Especially, sedges were not adequately controlled by carfentrazone-ethyl alone at any application rates examined. Glyphosate or glufosinate was more effective to control monocot weeds than carfentrazone-ethyl, whereas carfentrazone-ethyl exhibited higher effect on dicot weeds than glyphosate or glufosinate. Carfentrazone-ethyl mixed with glyphosate of the half recommended rate exhibited a higher degree of weed control, especially of E. crus-galli, as compared to the herbicide mixture of carfentrazone-ethyl with glufosinate of the half recommended rate. However, no phytotocixity of the herbicides to pear trees was observed. Our results demonstrate that catfentrazone-ethyl is useful to reduce the application rates and to accelerate the weed controlling effect of glyphosate or glufosinate. Thus, carfentrazone-ethyl in combination with glyphosate or glufosinate can successfully be used to control the most important weeds in orchards.

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Emergence of Weed Species and Their Competitive Characteristics in Direct-Seeded Rice (Oryza sativa) - 1. Distribution and Growth of Weeds in Direct-Seeded Rice (벼 직파재배(直播栽培) 양식(樣式)에 따른 잡초발생양상(雜草發生樣相) 및 경합특성(競合特性) - 제(第) 1 보(報). 잡초(雜草)의 발생분포(發生分布)와 생장(生長))

  • Huh, S.M.;Cho, L.G.;Kwon, S.L.
    • Korean Journal of Weed Science
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    • v.15 no.4
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    • pp.278-288
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    • 1995
  • Weed species occurred in dry- and water-seeded rice were 14 (2 grasses, 8 broadleaves, and 4 sedges) and 12 species (1 grasses, 7 broadleaves, and 4 sedges), respectively. Dominant weed species in dry-seeded rice were Lindernia procumbens, Cyperus difformis, Cardamine flexuosa, and Cyperus serotinus in discending order. The species in water-seeded rice were Cyperus difformis, Scirpus juncoides, and Lindernia procumbens. The number of weed species emerged in direct-seeded rice was determined at about 45 days after seeding, and dry weights of weeds were increased up to 75~90 days after seeding. Timing for great increase of plant height varied depending upon weed species. Regardless of weed number emerged, the most dominant weeds until late stage of growth were Cyperus difformis, Bidens frondosa, Digitaria ciliaris and Echinochloa crus-galli in dry- seeded rice, and Cyperus difformis, Echinochloa eras-galli and Scirpus juncoides in water-seeded rice.

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Plant Assemblages Along an Altitudinal Gradient in Northwest Himalaya

  • Gupta, Bhupendar;Sharma, Navneet
    • Journal of Forest and Environmental Science
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    • v.31 no.2
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    • pp.91-108
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    • 2015
  • The study investigates herbage communities along the altitudinal gradient in northwest Himalaya and highlights the effect of trees on its understory floristic diversity and phytosociology. The study was conducted in nine forests at three elevations viz., chir pine (Pinus roxburghii), mixed and khair (Acacia catechu) forests at elevation $E_1$ (850-1150 m), chir pine, mixed and ban oak (Quercus leucotrichophora) forests at elevation $E_2$ (1151-1600 m) and ban oak, mixed and chir pine forests at elevation $E_3$ (>1600 m) in a sub-watershed located in Solan district of Himachal Pradesh, India. These were compared grasslands located adjacent to forests. In all, 20 grass, 3 sedge, 2 forb and 4 legume species were recorded in study sites. Jaccard's coefficient of herbage vegetation was highest between chir pine forests and grasslands, and lowest in khair and ban oak forests. TWINSPAN dendrogram of herbage composition exhibited three subtypes with Apluda mutica, Arundinella nepalensis and Dichanthium annulatum as indicator species. Three groups of plant communities were identified on the basis of their moisture requirement. Peak density and basal area of herbage in forests and grasslands occurred by September. Density and basal area of herbage in grasslands at different elevations ranged from 649.6 to $1347.9tillers/m^2$ and 30.0 to $65.7cm^2/m^2$, respectively, while, in forests it varied from 351.2 to $1005.3tillers/m^2$ and 14.9 to $43.9cm^2/m^2$, respectively. Density and basal area of the herbage in plant communities decreased along the elevation. Under trees in forests the density of herbage decreased up to 77% and basal area up to 62% of their respective values in grasslands.

Influence of light Regime on Nitrate Reductase Activity and Organic and norganic Solute Composition of Four Sedges (Carex spp.)

  • Choo, Yeon-Sik;Roland-Albert;Song, Seung-Dal
    • Animal cells and systems
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    • v.2 no.4
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    • pp.455-462
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    • 1998
  • A survey was conducted on the inorganic and organic solute patterns of plants in connection with nitrate metabolism according to different light regimes (1.9, 16.0, 91.5 $Wm^{-2}$). Besides measuring in vivo NRA, we also quantitatively analyzed ater-soluble inorganic ions, organic acids, low molecular weight carbohydrates, amino aciss and total N (% DW). Among 4 Carex species, C. pilosa is known as shade-adapted species and the others as half (C. gracilis) to full (C. rostrata & C. distans) light-adapted species. Compared to species adapted to high light intensity, shade-adapted C. pilosa showed reduced productivity under the highest light intensity. In general, nitrate and amino acid levels decreased at higher light intensity, while sugar and organic acid concentrations increased. In C. pilosa osmolality tended to rise with increasing light intensity, while in the other species it tended to fall. Under low light intensity, the drop in soluble carbohydrate contents is osmotically compensated for by an enhanced nitrate concentration. It is concluded that competition between nitrate and $CO_2$reduction for reductants and ATP from photosynthesis may have important ecological consequences for the adaptation of plants to low or high light conditions. Additionally, the patterns of ionic changes due to increased light intensities were essentially the same in all selected species, indicating similar characteristics of heir mineral ion and organic acid metabolism as well as in field-grown Carex species.

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Image Data Compression Using Biorthgnal Wavelet Transform and Variable Block Size Edges Extraction (쌍직교 웨이브렛 변환과 가변 블럭 윤곽선 추출에 의한 영상 데이타 압축)

  • 김기옥;김재공
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.7
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    • pp.1203-1212
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    • 1994
  • This paper proposes a variable block size vector quantization based on a biorthogonal wavelet transform for image compression. An image is first decomposed with the biorthogonal wavelet transform into multiresolution image and the wavelet coefficients of the middle frequency bands are segmented using the quadtree sturcture to extract the perceptually important regions in the middle frequency bands. A sedges of middle frequency bands exist the corresponding position of high frequency bands, the complicated quadtree structure of middle frequency bands is equally applied to the high frequency bands. Therefore the overhaed information of the quadtree codes needed to segment the high frequency bands can be reduced. The segmented subblocks are encoded with the codebook designed at the each scales and directions. The simulation results showed that the proposed methods could reproduce higher quality image with bit rate reduced about 20(%) than of the preceding VQ method and sufficiently reduce the bolck effect and the edge degradation.

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Ecological Studies on the Improvement of Natural Pasture by Fertilization and Grazing (시비 및 방목에 의한 자연초지의 개량에 대한 생태학적 연구)

  • ;G. Spatz
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.6 no.3
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    • pp.138-144
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    • 1986
  • This trial was carried out to find out the methods of improvement of natural pasture by PK-fertilization and sheep grazing. The experimental area covered with the community of Carex ferruginea-dominated and located at the Bavarian Alps in the southern part of Germany. As measuring the changes of the vegetation, the Releve-method, the Point-Intercept-method and the Quadrat-Charting-method were applied. Changes in the ecological evidence of the vegetation were studied during the period from April 1980 to the end of growing season in 1983. 1. The fodder value at the oversown pasture we slightly increased by PK-fertilization with sheep grazing, byt that gradually decreased by grazing without fertilization. 2. The pasture quality at the secondary vegetation was greatly improved as well as that of the oversown pasture in Autumn of the second experimental year by sheep grazing with PK-fertilization, but the fodder value was not like that by grazing without fertilization at the natural pasture. 3. The influence of phosphorus/ potassium-fertilization was much more serious than that of sheep grazing. Sedges almost disappeared due to fertilization, on the other hand grasses and legumes increased distinctly. Sheep grazing without fertilization led to a gradual decrease of legumes. The enormous biomass difference in sedges between the June and October analyses was due to a lack of regenerative capacity. 4. The plant community of Carex ferruginea-dominated before the experiment was successived into Alchemillo-Cynosuretum by PK-fertilization with sheep grazing.

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Weed Occurrence in Lowland Rice Field in Gyeongbuk Province (경북지역 벼재배답에서 발생하는 잡초 분포)

  • Kim, S.J.;Kim, Y.H.;Lee, W.H.;Choi, C.D.;Kim, C.Y.;Choi, B.S.
    • Korean Journal of Weed Science
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    • v.17 no.3
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    • pp.262-268
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    • 1997
  • The experiment was carried out to obtain the basic information of weed control in lowland rice field in Gyeongbug province. The results were as follows : In weed distribution on life cycle, annual weed was occupied by 56.5% and perennials were 43.5%, respectively. In morphological distribution of weeds, grass weed was 25.2%, sedges was 12.3% and broad leaf weeds was 62.5%. In particular, weed occurrence of grass weed was much more increased than that of 1971 and 1981 year. Dominant weed species was Echinochloa crusgralli, Sagittaria trifolia, Eleocharis kuroguwai and Monochoria vaginalis in plain land, mid alpine area, and cold salty wind area. Dominant weeds was approximately similar occurrence in normal soil and poorly drained soil Gelds, but sandy soil field was not. Echinochloa crusgalli was dominant in hand transplanting and direct seeding on dry paddy field. Meanwhile, in machine transplanting, Sagittaria trifolia and Ludwigia prostrate were dominant, and occurrence of Echinochloa crusgalli was increased to delaying transplanting. As a result, major dominant weed was Echinochloa crusgalli, Sagittaria trifolia, Ludwigia prostrate, Eleocharis kuroguwai, and Monochoria vaginalis in terms of predominance.

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