• Korean Journal of Organic Agriculture
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• v.22 no.4
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• pp.773-787
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• 2014

Bacterial pustule of soybean caused by Xanthomonas axonopodis pv. glycines is one of the most prevalent bacterial diseases in many areas where soybeans are grown. This study was carried out to evaluate the effect of cultivars, sowing date and cropping system on the suppression of soybean bacterial pustule in the field. One hundred soybean cultivars were screened for disease resistance against bacterial pustule in naturally infested field. Among them, fourteen cultivars including 'Pureun' were found to be high resistant. And thirty cultivars showed to be moderate resistant(less than 3% of diseased leaf area). When Soybean cultivar 'Taekwang' were sown in four different dates, May 25, June 5, June 15, and June 25, at 10 day-interval in Milyang, the diseased leaf area of bacterial pustule was 23.3%-25.7%, 14.7%-18.0%, 10.7%-12.8%, and 1.0%-2.7%, respectively. The lowest percentage of diseased leaf area was recorded in the plots sown on June 25, whereas the highest percentage of diseased leaf area was recorded in the plot sown on May 25. As sowing time was delayed, incidence of soybean bacterial pustule found to be comparatively reduced. From December in 2006 to June in 2007, we surveyed the pathogen population of soybean bacterial pustule in five cropping upland soils where soybean was cultivated. The survey result showed the bacterial pustule pathogens were detected from the all cropping soils. The pathogen populations of soybean bacterial pustule in soybean-barley and soybean-garlic cropping soil were significantly lower than that of the other cropping soils. In addition, the incidence of soybean bacterial pustule was decreased under the two cropping systems.

• Journal of Korean Society of Forest Science
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• v.90 no.1
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• pp.10-18
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• 2001

Experiments were conducted to compare ozone sensitivity among clones. Ten clones of Papulus deltoides Marsh. were exposured in walk-in type chambers to charcoal-filtered air, 50ppb, 100ppb, and 150ppb ozone for 8h $day^{-1}$ for 21 consecutive days. Occurrence of premature leaf-fall, and visible foliar injury expressed as adaxial stipple were measured after termination of ozone exposure for 3 weeks. Rate of premature leaf-fall increased progressively according to ozone exposure levels. As a result, rate of premature leaf-fall was estimated over 50% at 150ppb ozone. In the charcoal-filtered air and 50ppb ozone treatments, visible foliar injury was not found. But injury was estimated as LA; 17.3%, AA; 6.5%, and LAA; 1.6% to 100ppb ozone treatment and LA; 34.1%, AA; 17.5%, and LAA; 7.4% to 150ppb ozone treatment. Clonal differences of sensitivity within the species were manifested by significant clone differences of adaxial stipple(LAA) in 100ppb and 150ppb ozone treatments.

• Korean Journal of Environment and Ecology
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• v.14 no.4
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• pp.252-267
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• 2001

계룡산국립공원 동학사-남매탑구간의 산림군집구조를 분석하기 위하여 64개 조사구를 설정하고 식생구조를 실시하였다. Classification의 기법 중 하나인 TWINSPAN을 이용하여 군집분리를 시도하였으며, 그 결과 소나무 군집(I), 굴참나무-소나무군집(II), 서어나무-굴참나무군집(III), 굴참나무-졸참나무군집(IV), 서어나무-까지박달군집(V), 신갈나무-서어나무군집(VI), 느티나무-졸참나무군집(VII) 그리고 느티나무군집(VIII)의 8개로 분리되었다. 연륜분석결과 이지역의 임령은 약 60년 안팍이었으며, 단위면적(100$\m^2$)당 평균출현종수는 15.0$\pm$3.2종. 평균출현개체수는 95.7$\pm$37.3주었다. 이상의 결과를 통해 계룡산국립공원이 동학사-남매탑구간 지역은 소나무림에서 굴참나무, 졸참나무, 신갈나무림을 거쳐 서어나무, 까지박달림으로 천이가 진행될것으로 예상되었다.

• Korean Journal of Environment and Ecology
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• v.17 no.1
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• pp.44-55
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• 2003

The wetland in the city could be mainly divided into the deep water type and the abandoned paddy type, so this study was conducted to analyze characteristics between the two types of the wetland. The former sample site was located near the Olympic village in Songpa-gu of Seoul, and the latter sample site was in front of the Mt. Bukhan fortress in Eunpyeong-gu of Seoul. The actual vegetation, vascular plants, and avian fauna were researched. In the actual vegetation, the deep water type had the broad surface of water and the emerged plant as Phragmites communis have grown widely, but the abandoned paddy type had the narrow sur-face of water and hydrophyte as Persicaria thunbergii have grown widely. It might be judged because the water depth of the abandoned paddy type were shallow wholly. And the floating-leaved plants and the free-floating planktonic plants were not observed such as Nymphaea tetragona var. angusta, Lemna paucicostata in the abandoned paddy type wetland. The wild birds were mainly observed at the edge of the wetland(at the edge of woodland) in the abandoned paddy type, but were observed equally in the deep water type. 28 families 433 species were observed at the former site and 32 families 365 species were observed at latter site. It was judged that the various topographical structure(habitat diversity) might make all items various.

• Korean Journal of Environment and Ecology
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• v.12 no.3
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• pp.290-296
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• 1998

Altitudinal changes in the vegetation of Sunginbong(984m) in UIlungdo (Island) were investigated by sample plots(forty l00$\m^2$) along elevation and analyzed by TWINSPAN and DCA techniques. In the results from the analysis of both techniques, altitudinal zonations were divided into 3 groups such as lower 300m area, 400~700m area, and above 800m area. DCA and similarity index analyses of elevational ranges showed discontinuities between lower and middle elevation areas. But there was a vegetation continuum between middle and high elevation areas. In the analysis of species diversity, there was no significant difference due to altitude except for maximum species diversity which was decreased with altitude. The mean tree density of canopy and understory layers in the middle elevation area showed the highest value, and the highest basal area was recorded at the lower elevation area.

• Korean Journal of Environment and Ecology
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• v.12 no.4
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• pp.317-330
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• 1999

To study the actual vegetation and vegetation structure of Tongyoung district and Yokjido (Island) in Hallyo-Haesang National Park, thirty seven plots were surveyed in July,1998. The vegetation structure of the surveyed plots were dissimilar in virtue of geographical isolation and artificial disturbance. The actual vegetation were classified into five group: Pinus thunbergii forest, P. thunbergii-P. densiflora- deciduous broad-leaved forest, deciduous broad-leaved forest, P. thunbergii-P. densiflora-evergreen broad-leaved forest, evergreen broad-leaved forest. P. thunbergii forest was a major vegetaion type of the surveyed area and evergreen broad-leaved forests were distributed at Ch'ubongdo, Yongch'odo, Pijindo, Yokjido and Youjado as a small patch. Successional sere shall be assumed from Pinus thunbergii, Pinus densiflora, and deciduous broad leaved trees to Neolitsea sericea, Cinnamomum japonicum and Persea thunbergii via Castanopsis sieboldii.

• Korean Journal of Environment and Ecology
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• v.28 no.1
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• pp.33-44
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• 2014

The purpose of this study was to provide basic information and investigate a vegetation structure around Tohamsan (Mt.) Wetland. Actual vegetation map was made on the basis of watershed around that. Vegetation structure survey was carried out for 8 representative communities of actual vegetation which were Pinus densifrora community, Quercus variabilis community, Cornus controversa community, Q. serrata community, Q. mongolica-Q. serrata community, Salix koreensis community, Q. mongolica community, Q. variabilis-Q. mongolica-Q. serrata community. Tohamsan (Mt.) Wetland is located on 490m above sea level and the area of watershed was $236,272m^2$. Vegetation type were divided into 16 types, and the ratio of Q. mongolica community was 33.1% ($78,209.2m^2$). In order to turn out the structure of 8 representative communties, 32 plots were set up and unit area of plot was $100m^2$. The estimated age of forest is 30~50-years-old, and in the resutls of soil analysis, acidity was pH 4.89 and organic matter was 4.46%.

• Research in Plant Disease
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• v.13 no.1
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• pp.20-23
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• 2007

We investigated the first symptom emerging date of rice bacterial leaf blight disease during four years from 2002 to 2005. The disease occurrence date was earlier 20$\sim$30 days in 2005 than that of 2002. The damage in different rice growth stage by the bacterial disease on rice yield and grain quality in southern part of Korea was examined. The disease decreased rice yield following by increased infection rates. Slight loss in rice yield and brown head rice rate were observed at below 10% level of infected leaf area, while over 25% infected leaf area caused the significant decrease in rice yield and brown head rice rate. More than 50% of the infected leaf area rate caused 29% yield reduction in case of infection at panicle formation stage and 18% of brown head rice rate. Cooked rice quality was also affected in the diseased rice by damage in palatability score and viscosity.

• Journal of Ginseng Research
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• v.26 no.1
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• pp.6-9
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• 2002

This study was undertaken to evaluate the automatic decision-making on the rusty root of fresh ginseng (Panax ginseng C.A. Meyer) by an image analyzer. Critical value of rusty root of ginseng by image analyzing was the percentage of grey value 0∼148 area (G 148) to the total area of grey value 0∼255. And the discriminant formula of rusty root of ginseng as follows; rusty root of ginseng : 6.68$\times$G(148) +3.74, normal ginseng : 2.86$\times$G(148) +9.96, and fitness rates of this formula were 89.8%. Also, we developed the automatic rusty root of decision-making program. As the result of this study, the automatic decision-making on the rusty root of fresh ginseng by an image analyzer seems to have high possibility.

• Korean Journal of Agricultural Science
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• v.2 no.1
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• pp.143-149
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• 1975

To obtain some basic informations on the breeding of Kudzu, 42 individuals were selected and their morphological characteristics were investigated and analyzed. The shape of leaves was classified as 4 types and area of leaves into 5 steps. Internode length was distributed between 13 cm and 37 cm. Significant correlations were recognized between petiole and leaf area, between internode length and internode diameter and between internods diameter and leaf area.