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Suppressive Mechanism of Soil-borne Disease Development and its Practical Application -Isolation and Identification of Species of Trichoderma Antagonistic to Soil diseases and its activities in the Rhizosphere- (토양병의 발병억제 기작과 그 실용성 -길항성 Trichoderma spp.의 분리, 동정 및 근권내 활동-)

  • Kim, S.I.;Shim, J.O.;Shin, H.S.;Choi, H.J.;Lee, M.W.
    • The Korean Journal of Mycology
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    • v.20 no.4
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    • pp.337-346
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    • 1992
  • Trichoderma spp. are an effective control agent for damping-off or other plant diseases. The interaction between. T. hamatum and Rhizoctonia solani on the rhizosphere or surface soil were examined to assess the possible roles of antibiosis or competition in the mechanisms of biological control agents as a basic research. In a proportional comparison, total bacteria, fungi, actinomycetes and Trichoderma spp were 65%, 8.8%, 25.9% and 0.28% respectively in their distribution in the soil. Among Trichoderma spp isolated, the 5 species of Trichoderma spp were indentified as T. koninggii, T. pseudokoninggii, T. aureoviridi, T. hamatum and T. viride respectively. In a mycoparasitic test, one isolate of T. hamatum strain Tr-5 showed an enzymatic ability to break fungal hyphae into piecies and infected on the R. solani hyphae showing a parasitism. Spore germination of the all isolates of Trichoderma spp showed a 1.7-7.3% of germination in natural soil conditions, but the percentage was high in sterile soil indicating all the natural soil were fungistatic on conidia of Trichoderma spp. In rhizosphere competent assay in pea plant, the antagonistic T. hamatum, T. viride, T. koninggii, T. pseudokoninggii showed a colonizing upper soil depth in rhizosphere around 1-3 cm in root zone, but the colonizing ability was much reduced along the deeper the soil depth. Propagule density was decreased in deeper the soil layer. Disease development rate treated alone with plant pathogens, Fusarium solani, Rhizoctonia solani, Cylindrocarpon destructans increased, but disease incidence rate reduced in treatment with combinations with antagonistic T. hamatum strain Tr-5.

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Size Dependent Analysis of Phytoplankton Community Structure during Low Water Temperature Periods in the Coastal Waters of East Sea, Korea (저수온기 동해연안의 식물플랑크톤 크기에 따른 군집구조)

  • Lee, Juyun;Chang, Man
    • Korean Journal of Environmental Biology
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    • v.32 no.3
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    • pp.168-175
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    • 2014
  • In order to understand the phytoplankton community structure based on their cell size duringlow water temperature periods, we studied 10 stations in the East Sea, Korea on March, 2012. The minimum standing crops of total phytoplankton were $3.4{\times}10^6cells\;L^{-1}$ at the station 5. The maximum values were $7.6{\times}10^6cells\;L^{-1}$ at the station 8, which is two times the amount of the minimum. The carbon mass at the station 4 ($6.3{\times}10^8pg\;L^{-1}$) was more than forty times higher compared with station 5 ($0.08{\times}10^8pg\;L^{-1}$). From these results, we found a significant difference between standing crops and carbon mass which might have caused due to their differences in community structure and cell size. Therefore, we considered the types of plankton biomass to estimate the primary product in the specific location and/or time. The phytoplankton communities were classified in 3 types: microplankton (> $20{\mu}m$), nanoplankton (< $20{\mu}m$) and picoplankton (< $2{\mu}m$). In the case of picoplankton, various morphological types were observed during the study period. These various picoplankton species were further classified as S (spherical), SF (spherical&flagella), O (oval), OF (oval&flagella) or R (rod) type, and we analyzed their community structure based on these categories. The picoplankton was found to be the most dominant type at 8 stations and S type as the most popular. The picoplankton seems to be the significant organism in the marine ecology during low water temperature periods in the coastal waters of East Sea. Therefore, picoplankton \;-with scientific surveys can be considered as the database for their identification. In conclusion, we suggest that cell size of the phytoplankton would be the best criteria to accurately analyze their community structure and to reveal groups having more ecological influence.

A Study on Luxury Prohibition of Korean Personal Ornaments (한국장신구의 사치 금제 고찰)

  • 추원교
    • Archives of design research
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    • v.2 no.1
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    • pp.43-62
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    • 1989
  • The luxury is the expression of human being's ornament instinct. In this study, in order to grasp the moulding system of the Korean's personal ornaments, the process of luxury prohibition was reviewed to search for to which direction the ornaments developed in the frame of the prohibited style connected closely to the character of the personal ornaments. The proiod was fixed from the old society to the late Chosun dynasty era. The beginning of the luxury in Korea seems to be the start of the luxury burial at the time of funeral in the age of Koguryo., In the era of Koguryo, 10th year of King Dongmyung (B. C. 28), in the era of Baekje, 27th year of King Koi(260), the prohibition of dress regulation and the style of dress were conducted. The prohibition of personal ornaments in Silla was started from King Bup:Heung, and in the 9th year of King Heung-Duk, the prohibition was conducted in order to correct the luxury of the nobles and set up the social discipline. In the 11 th of King Il-Sung-Ni-Sa-Kum, the use of gold, silver and jade was prohibited in the civilian circles. The prohibition of Silla was succeeded to Koryo era, and in the 7th year of King Kwangjong(956), the system of Baekgwan Gongbok(uniform for government officials) was set up, and the system of Sasek Gongbok(four color official uniform) was set up in the 11 th year of the same King, and the prohibition of the personal ornaments such as crown and band is considred to have been conducted. The prohibition of gold and silver was conducted in the first year of King Sungjong(982), and in the 4th year of King Chungryul(l260), the order of wearing the dress and hat in accordance with the Yusan dynasty and the Mongolian customs were widely circulated in the royal court and vivilian circles. The strong influence of Mongolia made the taste of the traditional personal ornaments laste. The personal ornaments were used for the nobles until the age of the Unified Sillar but even the common people could use them in case they were rich, and such a circumstances made the use of foreign goods inflated. The prohibition of Koryo era was aimed at the prohibition of the foreign goods of luxury, and the classification of the social status.In the age of Chosun Dynasty, the production of gold and silver was feeble indeed but the oute reason of the prohibition was to eradicate the luxurious tendency, elevate the custom of eradicate the luxurious tendency, elevate the custom of thrift, and moreover, the gold, silver and jade were no the products of Korea and the prohibition was conducted but the true reason was afor the tribute tt China and the classification of status. The prohibition of Chosun dynasty was conducted first in the June of the 3rd year of King Taejo The major contents of prohibition was no use of gold, silver and jade, coral, agate, amber, etc. of th, wives of the Dang-Sang-Kwan (Court Nobleman) or their sons and daughters, and the same pheno menon was common even at the time of marriage. The people engaged in the secret trade there of wert beheaded. The personal ornaments in the prohibition were the pendent trinket, Binyo (crossbar) ceremonial ornamental hat, ring, earring, ornamental knife, hat string, hat ornament, belt, etc. Thl luxurious marriage expenses out of the luxury was severe, and lose of the marriageable age because 0 non-preparing the marriage goods was the national evil. The prohibition oC luxury was hard to bt kept to the nobles or rich people, the same as old days and present days. The prohibition of th{ luxury and personal ornaments of Korea had nothing to do with the commons, and it was limited tc the nobles and rich people. The prohibition was aimed to cultivating the custom of frugality by eradicating the luxurious atmosphere, but it was chiefly due to the tribute to the China and tht discrimination of the. status. We can say that the recent personal ornament was the flower of handi craft industry bloomed in the prohibition and regulation.

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Comparison of Forage Yield and Quality, and Soil Improvement of Legumes (콩과작물의 사초생산성, 품질 및 토양개량 비교)

  • Kim Jong Duk;Kim Su Gon;Kwon Chan Ho;Abuel Sherwin J.;Chae Sang Heon;Kim Myoung Ki
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.3
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    • pp.151-158
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    • 2005
  • This experiment was conducted to evaluate forage production and quality, and soil improvement of three legumes at Cheonan Yonam College. The three legumes used in the experiment were crimson clover (Trifolium incarnatum L.) red clover(Trifolium pratense L.) and chinese milk vetch(Astragalus sinicus L.). Flowering stage was observed on the 20th of April for chinese milk vetch and on the 30th of April for crimson clover, but the red clover did not produce flower until harvest time. The dry matter(DM) content of crimson clover was the highest among the three legumes. In terms of DM yield, crimson clover has the highest yield, the highest yield in crude protein(CP) and total digestible nutrients(TDN) was red clover. In terms of forage quality, the highest CP content was red clover, while the chinese milk vetch was the lowest for both neutral detergent fiber(NDF) and acid detergent fiberr(ADF). Red clove. and chinese milk vetch were highest fur TDN content, and the chinese milk vetch has the highest for relative feed value(RFV). Assessment of the chemical properties of soil after harvest showed that the nitrogen content of soil increased in all legumes. The organic matter(OM) content of soil in both crimson and red clover increased, while the chinese milk vetch decreased. The available $P_2O_5$ decreased in all three legumes, but the biggest decrease was in the chinese milk vetch. The exchangeable potassium in the soil for both crimson and red clover increased, but in chinese milk vetch it decreased. Based on the results of this study, the chinese milk vetch was superior in terms of forage quality, but crimson and red clover are excellent in forage yield and in maintaining soil quality in upland.

Information on Movement of the Phosphorus(P) Fertilizers in the Turfgrass Soils of Golf Course (골프장의 잔디 토양에서 인산 비료의 이동성 평가를 위한 정보 구축)

  • Chung, Keun-Yook;Baek, Ki-Tae;Ko, Seong-Hwan;Noh, Jae-Goan;Lee, Kyung-Ho;Woo, Sun-Hee
    • The Journal of the Korea Contents Association
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    • v.8 no.8
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    • pp.285-292
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    • 2008
  • This study was initiated to evaluate the Phosphorus(P) leaching potential in the putting green soils and P uptake by the turfgrass in the golf course using the P fertilizers. The turfgrass, Floradwarf bermudagrass(Cynodon dactylon L. PERS,) was planted and grown in the mixture of sand and peat moss in this lysimeter study. Five representative P fertilizers, such as, ammonium polyphosphate (APP), monopotassium phosphate (MKP), MAP(monoammonium phosphate), 0-20-20(liquid), and concentrated superphosphate(CSP, solid) were used in this study. Based on the total P quantity of leachate collected during the whole 12 weeks, MKP and APP are the first group of P fertilizers contributing to the leaching of P, then MAP and 0-20-20 are the second group of P fertilizers causing the P leaching. Finally, CSP is the third group of P fertilizer resulting in the P leaching. However, most of P applied and collected in the lysimeter were leached during the first period of two and four weeks, compared to that of P leached during the second period of six, eight, ten, and twelve weeks. Applications of MAP, APP and CSP, MKP and 0-20-20 in order produced the largest amount of total dry matter. However, APP, MKP and MAP, CSP and 0-20-20 in order showed the largest amount of P uptake. Therefore, based on the data of P leaching, dry matter production, and plant P uptake, it appears that CSP, 0-20-20, and MAP are the environmentally sound fertilizers recommended in the turfgrass putting green soil of golf course.

The Effectiveness of Spiral Computed Tomography as a Diagnostic Tool in Pulmonary Embolism(Comparison of Spiral CT with Ventilation-Perfusion Scan) (폐색전증 진단의 도구로서의 Spiral Computed Tomography의 유용성(폐환기관류주사와의 비교))

  • Koh, Jae-Hyun;Oh, Eun-Young;Park, Jung-Ho;Park, Sang-Joon;Yun, Jung-Hwan;Park, Jung-Woong;Suh, Gee-Young;Chung, Man-Pyo;Lee, Kyung-Soo;Kwon, O-Jung;Rhee, Chong-H.
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.4
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    • pp.564-573
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    • 1999
  • Background: With variable symptoms and nonspecific radiographic appearances, pulmonary embolism (PE) is a frequent and often undiagnosed cause of mortality and morbidity. The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study suggested that the majority of patients undergoing ventilation-perfusion (V-Q) scan would require additional studies to establish or to exclude the diagnosis of PE. Pulmonary angiography has been regarded as gold standard for diagnosis of PE. However, it is an invasive procedure that may be associated with significant notable morbidity and mortality. Thus, availability of an accurate, noninvasive screening examination is highly desirable. Method: From October 1994 to February 1997, twenty patients (male 13, female 7, range 23-91 years, median 58 years) who were suspected as pulmonary embolism on the basis of clinical evidence and underwent the spiral volumetric computed tomography (spiral CT), were studied retrospectively to evaluate the effectiveness of spiral CT as a diagnostic tool in PE. Results: PE could be excluded with spiral CT in 4 patients ; diagnoses of these patients were lung cancer, pneumonia with lung abscess, bilateral pleural effusion due to congestive heart failure, nonspecific pulmonary abnormality retrospectively. One patient who disclosed high probability in V/Q scan, could be diagnosed as pneumonia with lung abscess and underlying emphysema with spiral CT. Among 4 patients who showed intermediate and low probability in V/Q scan, 3 patients could be confirmed as PE with spiral CT. Spiral CT was helpful in 3 patients, in whom V/Q scan could not be performed due to other reasons (e.g. night time, mechanical ventilation) to confirm the diagnosis of PE. Spiral CT could demonstrate embolus above lobar artery level in 11 patients, and up to segmental artery level in 5 patients. Conclusion: This study demonstrated that spiral CT could allow accurate demonstration of thrombotic clots in centrally localized embolism. Spiral CT could be effective, specific, noninvasive and useful diagnostic screening modality for the diagnosis of pulmonary embolism.

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Effect of Liming on the Extractability of Phosphate Added to Uncultivated Acid Soil (미경지(未耕地)의 산성토양(酸性土壤)에서 시용인산(施用燐酸)의 침출성(浸出性)에 미치는 석회(石灰)의 영향(影響))

  • Yoo, Sun-Ho;Lee, Won-Chu;Park, Sung-O
    • Applied Biological Chemistry
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    • v.20 no.1
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    • pp.88-94
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    • 1977
  • A laboratory study was made of liming on the extractability of phosphate added to the uncultivated acid soils differing in clay content. The experiments were conducted with different rates of calcium carbonate and triple superphosphate at field capacity and 50% field capacity. The concentration of extractable phosphate was greatly reduced by simultaneous addition of calcium carbonate in the loam soil. When samples of the loam soil were preincubated for ranging from 0 to 50 days in the presence of calcium carbonate prior to phosphate application, the extractable phosphate concentration increased with preincubation time, and more phosphate was extracted from the soil maintained at 50% field capacity during the incubation. However, the extractable phosphate concentration in the sandyloam soil did not change with preincubation time and was not affected by moisture status. It may be concluded that the extractability of added phosphate was influenced by not only liming time but physical properties of soil.

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Eruption Styles and Processes of the Dongmakgol Tuff, Cheolwon Basin, Korea (철원분지 동막골응회암의 분출유형과 분출과정)

  • Hwang, Sang Koo;Son, Yeong Woo;Choi, Jang O;Kim, Jae Ho
    • The Journal of the Petrological Society of Korea
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    • v.22 no.1
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    • pp.49-62
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    • 2013
  • The Dongmakgol Tuff is divided into 8 lithofacies based on their grain size and depositional structures: massive tuff breccia(TBm), welded tuff and lapilli tuff(LTw), rheomorphic tuff and lapilli tuff(LTr), massive lapilli tuff(LTm), stratified lapilli tuff(LTs), gradedly bedded lapilli tuff(LTg), crudely bedded lapilli tuff(LTb) and massive fine tuff(Tm). They can be divided into 3 pyroclastic rock group based on their constituents of the lithofacies. The lower group(LI) is composed of LTm, LTw and LTr, which are interpreted to have resulted from emplacement of voluminous pyroclastic flows due to ignimbrite-form eruption to boiling-over eruption. The middle group(LT+MI) consists of LTs, LTg and LTm associated with Tm in the lower part, and of LTm, LTw and LTr in the middle and upper parts; these suggest that started with deposition of pyroclastic surges from phreatoplinian eruption by poor eternal water, passed through emplacement of pyroclastic flows from ignimbrite-form eruption and ended with deposition of voluminous pyroclastic flows from boiling-over eruption. The upper group(lUT+uUT+UI) is composed of LTs, LTg and Tm in the lowermost, TBm, LTb, LTb and Tm in the lower part, and LTm and LTw in the middle and upper part, suggesting that began with deposition of surges from phreatoplinian eruption, passed through deposition of pumice- and ash-fallouts from plinian eruption and transformed into emplacement of pyroclastic flows due to boiling-over eruption. As result, eruptive processes in the Dongmakgol Tuff approximately began with phreatoplinian or/and plinian eruption, transformed into ignimbrite-forming eruption and proceeded into boiling-over eruption in each volcanism, but proceeded presumably without phreatoplinian or plinian eruption in the earlier stage of 1st volcanism.

Prediction Model of Weed Population in Paddy Fields - II. Simple Prediction Method of Weed Population and Prediction Model of Weed Species (논 잡초(雜草) 발생예측(發生豫測) 모델 개발연구(開發硏究) - II. 간역(簡易) 잡초발생(雜草發生) 예측법(豫測法) 및 잡종별(雜種別) 예측(豫測)모델)

  • Lee, Han-Gyu;Lee, I.Y.;Ryu, G.H.;Lee, J.O.;Lee, E.J.
    • Korean Journal of Weed Science
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    • v.14 no.3
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    • pp.163-170
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    • 1994
  • The experiment was conducted in 1993 to find out a simple prediction method of weeds and to make the prediction models of weeds in paddy fields. The annuals producing fine seeds were apt to emerge at sampling soil only, on the contrary the perennials and the annuals producing large seeds tended not to emerge at sampling soil due to the miss of seeds at sampling. There was no appropriate regression between a total number of weeds emerged at sampling soil and that of weeds occurred in fields. The important annual weeds occurring in fields were able to predict by the number of weeds emerged at sampling soil, but it was difficult to predict the important perennial weeds. In case of Bidens tripartita producing large seeds and Eleocharis kuroguwai producing large tubers, the prediction coefficients were high as above 1.0, and that of Echinochloa crus-galli and Sagittaria pygmaea were comparatively high as 0.175 and 0.172, respectively. However the coefficients of the other weeds were much low as below 0.08. The prediction models for 9 species were made. The model of six species including E. crus-galli, M. vaginalis, R. indica, B. tripartita, E. triandra and S. pygmaea were linear regression with high significance, however that of 3 species including C. difformis, S. juncoides and E. kuroguwai were curve regression with high significance.

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Analysis of Genetic Diversity and Relationships of Korean Native Goat Populations by Microsatellite Markers (MS 표지를 이용한 한국재래염소 집단의 유전적 다양성 및 유연관계 분석)

  • Suh, Sangwon;Byun, Mijeong;Kim, Young-Sin;Kim, Myung-Jick;Choi, Seong-Bok;Ko, Yeoung-Gyu;Kim, Dong-Hun;Lim, Hyun-Tae;Kim, Jae-Hwan
    • Journal of Life Science
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    • v.22 no.11
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    • pp.1493-1499
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    • 2012
  • The level of genetic variation and relationships in three native Korean goat populations (Dangjin, Jangsu, and Tongyeong) as well as the populations of a farm were analyzed, based on 30 microsatellite markers. A total of 277 distinct alleles were observed across the four goat populations, and 102 (36.8%) of these alleles were unique to only one population. The mean observed heterozygosity and polymorphism information content were calculated as 0.461~0.651 and 0.462~0.679, respectively. In the NJ tree constructed based on Nei's $D_A$ genetic distance, the four populations represented four distinct groups. However, the genetic distances between each Korean native goat population and the farm population were two times those among the three native Korean breeds. The genetic structure within the three Korean native goat populations was also investigated. Cluster analysis, using the STRUCTURE software, suggested three clusters. The molecular information of genetic diversity and relationships in this study will be useful for the evaluation, conservation, and utilization of native Korean goat breeds as genetic resources.