• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.298-308
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• 2009

A flexuous rod-shaped virus was isolated from Cucurbita pepo leaves showing as green mosaic and puckering symptoms at Anseong, Korea. Based on the biological analysis, electron microscopy, and reverse transcription-polymerase chain reaction (RT-PCR), the virus isolate was identified as Papaya ringspot virus type watermelon (PRSV-W). From biological analysis, the host range of PRSV-W was limited to the families Cucurbitaceae and Chenopodiaceae. Most susceptible cucurbit species, such as Cucumis lanatus, Cucumis sativus, Cucurbita pepo, and Citrullus lanatus, showed symptoms of green mosaic, malformation, puckering, and narrow laminae by infection with PRSV-W. The local lesion were showed on the inoculated leaves of both Chenopodium amaranticolor and C. quinoa. Field survey of PRSV, Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV), three major viruses infecting cucurbit, was done during 2001 to 2003 on 173 commercial cucurbit cultivating fields distributed over the three regions of Gyeonggi, Gyeongbuk and Jeonnam Provinces where cucurbits are grown in different environmental conditions and cropping patterns. Typical viral symptoms were observed from 107 cultivating fields, and all three kinds of potyviruses were detected from 206 samples out of the 235 samples using RT-PCR. Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV) are the most widely distributed viruses in outdoor and retarding-culture fields, at an infection rating of 48 and 33 percents, respectively. PRSV was detected from 12 percent of 235 samples. The nucleotide and amino acid sequences of coat proteins (CP) of eight PRSV isolates, collected from several areas including Anseong, were determined and sequenced heterogeneity among the isolates was performed. The CP gene of PRSV showed 88.6~97.3 percent homology in nucleotide sequences and 95.1~99.3 percent homology in amino acid sequences with other PRSV isolates worldwide. The phylogenetic analysis indicated that the Korean PRSV isolates belong to the southern-east Asian cluster.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.3
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• pp.67-75
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• 2017

The culture of Gugok (九曲) and Dongcheon (洞天), which tries to reach the ideological culmination in Confucianism, was widespread throughout the Joseon dynasty. This was an extension of the spirit of studying and honoring Zhu Xi (學朱子, 尊朱子); thereby, Confucian scholars in Joseon expressed the will to follow the teachings of Zhu Xi (朱子) and comforted themselves that they were in the course of attaining the truth. As a realization of this expression of will, scholars designated and operated various scenic sites as Gugoks, following the example of Zhu Xi's Mui Gugok (武夷九曲), and Dongcheons, as a representation of the utopia. These designations are widespread nationwide, with around sixty Gugok locations that have now been reported in academia. However, the actual number of Gugoks exceeds this number, and many of them are currently not identified concerning the exact locations. Therefore, the purpose of this study is to identify the locations of Gugoks and Dongcheons scattered around Seoul, Gyeonggi and Gangwon regions. For the coordinates of Gugoks and Dongcheons, this study referred to the literature, web search and the books published by local cultural institutes. Based on the collected information, the researchers conducted field trips to investigate whether the record exists as a real location and, if so, acquired their coordinates. This study also provides the tables of Gugok or Dongcheon that only exists in the imagination, existed before but now are lost, or are inaccessible. Eight locations in Seoul, Gyeonggi, and Gangwon regions are understood as Gugok. Among them, Gogun Gugok and Okgye Gugok have relatively clear locations and records. Byeokgye Gugok and Suhoe Gugok, on the other hand, has many locations and titles overlapped, and their established time and managers are unclear. As for Ui Gugok in Seoul, it is known to be set by Hong Yangho, but some parts of its locations are confirmed, others are in dispute, and many locations are damaged. Thirty-eight locations in Seoul, Gyeonggi, and Gangwon regions are understood as Dongcheon. There are sixteen Dongcheons in Seoul area. Among them, those including Dohwa Dongcheon, Yangsan Dongcheon, and Ssangnyu Dongcheon actually exist but are forbidden to be accessed. There are thirteen Dongcheons in Gyeonggi area. The exact location of Onsu Dongcheon cannot be confirmed because of the development; Gwirae Dongcheon has historical records, but the actual existence cannot be confirmed. There are nine Dongcheons in Gangwon area. The researcher judged that Hwaeum Dongcheon is the misspelled record of Hwaeumdong Jeongsaji (華陰洞精舍址), which is located at the upstream of Gogun Gugok.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.191-199
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• 2018

This study was to investigate the occurrence patterns of paddy weeds, their resistance levels to an ALS inhibiting herbicide, and to estimate the areas of resistance in these paddy fields. We used soil collected from 358 paddy fields of Jeonnam province in 2017. Based on their life cycles, weeds were 96% annuals and 4% perennial. Additionally, according to morphological classification, 59% were broad leaves, 28% were sedges and 13% were grasses. Different areas within Jeonnam province contained different numbers and occurrence rates of weed species. However, generally, we observed Lindernia dubia var. dubia, Monochoria vaginalis var. plantaginea, Ludwigia prostrata, L. procumbens, Cyperus difformis, Scirpus juncoides, Eleocharis Kuroguwai, Echinochloa oryzoides, and E. crus-galli var. echinata. We also observed seven weeds resistant to an ALS inhibiting herbicide. They were M. vaginalis, S. juncoides, C. difformis, L. dubia, Ludwigia prostrata, E. oryzoides, and E. crus-galli var. echinata. Although there were differences in the number and occurrence rate of resistant weed species to an ALS inhibiting herbicide among areas in Jeonnam province, the M. vaginalis, C. difformis, and S. juncoides occurred in 23 cities and counties in Jeonnam including Gwangju metropolitan city. Based on the rates (52%) of resistant occurrence to an ALS inhibiting herbicide in Jeonnam province, the area of weed resistant paddy fields was estimated to be 91,543 ha.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.4
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• pp.484-489
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• 2010

The cultivation of green manure crops plays an important role in soil quality and sustainability of agricultural system. However, the incorporation of green manure crops may be of concern because it can lead to strongly reducing conditions in the submerged soil. This study was conducted to evaluate the effects of rice husk carbon on rice (Oryza sativa L.) cultivation using green manure mixtures (hairy vetch + rye) in rice paddy. Field experiments were conducted in rice paddy soil (Shinheung series, fine loamy, mixed, nonacid, mesic family of Aeric Fluventic Haplaquepts) at the National Institute of Crop Science (NICS), Korea from October 2007 to October 2008. The experiments consisted of three treatments: application or no application of carbonized rice husk, and conventional fertilization. These treatments were subdivided into whole incorporation and aboveground removal of green manure mixtures. The redox potential (Eh) was higher upon application of the carbonized rice husk when compared to no application at 8 and 37 days after transplanting (DAT). The ammonium-N ($NH_4$-N) in soil was highest upon the application of carbonized rice husk + whole green manure incorporation at 17 and 49 DAT. Plant height and tiller number of rice were similar to the $NH_4$-N concentration in soil. Rice yields of application and no application of carbonized rice husk treatment were not significant. However, application of carbonized rice husk improved the soil physical properties such as bulk density and porosity after rice harvest. Therefore, the results of this study suggest that carbonized rice husk could be used as soil amendment for environmentally-friendly rice production under a green manure mixture-rice cropping system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.3
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• pp.666-671
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• 2003

Dental caries are the most commonly occurring chronic diseases in the dental field. Because of increasing sugar consumption and extension of average human life, these diseases are widely found all over the world as the most typical cause for a person to lose a tooth. Therefore, the development of more effective, substantial and safe preventive agents against dental caries is strongly required. Streptococcus mutans is known as the causative bacterial playing the most important role informing plaque and it is being noticed as major causative bacteria of dental caries. The present study was designed to investigate the effect of Asarum sieboldii Miquel(Aristolochiaceae) extracts on the growth, acid production, adhesion, and insoluble glucan synthesis of Streptococcus mutans(S. mutans). Both methanol and aqueous extracts showed concentration dependent inhibitory activity against the growth and acid production of S. mutans, and produced significant inhibition at the concentration of 100, 1,000 and 2,000 μg/ml compared to the control group(p<0.05 - p<0.01). The extracts markedly inhibited S. mutans adherence to HA treated with saliva, and cell adherence was repressed by more than 50% at the concentration of 10 μg/ml and complete inhibition was observed at the concentration of 2,000 μg/ml. On the activity of glucosyltransferase which synthesizes water insoluble glucan from sucrose, methanol and aqueous extracts showed more than 70% inhibition over the concentration of 1,000 μg/ml. Hence, we conclude that Asarum sieboldii might be a candidate of anticaries agent.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.107-107
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• 2017

Sweet corns are enjoyed worldwide as processed products and fresh ears. Types of sweet corn are based on the gene(s) involved. The oldest sweet corn type has a gene called "sugary (su)". Sugary-based sweet corn was typically named "sweet corn". With its relatively short shelf life and the discovery of a complementary gene, "sugary enhanced (se)", the sweet corn (su only) was rapidly replaced with another type of sweet corns, sugary enhanced sweet corn, which has recessive homozygous su/su, se/se genotype. With the incorporation of se/se genotype into existing su/su genotype, sugary enhanced sweet corn has better shelf life and increased sweetness while maintaining its creamy texture due to high level of water soluble polysaccharide, phytoglycogen. Super sweet corn as the name implies has higher level of sweetness and better shelf life than sugary enhanced sweet corn due to "shrunken2 (sh2)" gene although there's no creamy texture of su-based sweet corns. Distinction between sh2/sh2 and su/su genotypes in seeds is phenotypically possible. The Involvement of se/se genotype under su/su genotype, however, is visually impossible. The genotype sh2/sh2 is also phenotypically epistatic to su/su genotype when both genotypes are present in an individual, meaning the seed shape for double recessive sh2/sh2 su/su genotype is much the same as sh2/sh2 +/+ genotype. Hence, identifying the double and triple recessive homozygous genotypes from su, se and sh2 genes involves a testcross to single recessive genotype, chemical analysis or DNA-based marker development. For these reasons, sweetcorn breeders were hastened to put them together into one cultivar. This, however, appears to be no longer the case. Sweet corn companies began to sell their sweet corn hybrids with different combinations of abovementioned three genes under a few different trademarks or genetic codes, i.g. Sweet $Breed^{TM}$, Sweet $Gene^{TM}$, Synergistic corn, Augmented Supersweet corn. A total of 49 commercial sweet corn F1 hybrids with B73 as a check were genotyped using DNA-based markers. The genotype of field corn inbred B73 was +/+ +/+ +/+ for su, se and sh2 as expected. All twelve sugary enhanced sweet corn hybrids had the genotype of su/su se/se +/+. Of sixteen synergistic hybrids, thirteen cultivars had su/su se/se sh2/+ genotype while the genotype of two hybrids and the remaining one hybrid was su/su se/+ sh2/+, and su/su +/+ sh2/+, respectively. The synergistic hybrids all were recessive homozygous for su gene and heterozygous for sh2 gene. Among the fifteen augmented supersweet hybrids, only one hybrid was triple recessive homozygous (su/su se/se sh2/sh2). All the other hybrids had su/su se/+ sh2/sh2 for one hybrid, su/su +/+ sh2/sh2 for three hybrids, su/+ se/se sh2/sh2 for three hybrids, su/+ se/+ sh2/sh2 for four hybrids, and su/+ +/+ sh2/sh2 for three hybrids, respectively. What was believed to be a classic super sweet corn hybrids also had various genotypic combination. There were only two hybrids that turned out to be single recessive sh2 homozygous (+/+ +/+ sh2/sh2) while all the other five hybrids could be classified as one of augmented supersweet genotypes. Implication of the results for extension service and sweet corn breeding will be discussed.

• Economic and Environmental Geology
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• v.40 no.2 s.183
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• pp.223-236
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• 2007

The eastern extension of the Cordilleran-type orogenic belt continues from southeastern China to the Chukot Peninsula through the Korean Peninsula. The Gyeongsang basin, located in the southeastern part of the Korean Peninsula and the Inner Zone of southwest Japan are characterized by extensive distribution of Cretaceous to Tertiary I-type calc-alkaline series of intrusive rocks. These intrusive rocks are possibly the result of intensive magmatism which occurred in response to the subduction of the Izanagi Plate beneath the northeastern part of the Eurasian Plate. The Jindong granitoids within the Gyeongsang basin are reported to be adakites, whose signatures are high $SiO_2,\;Al_2O_3$, Sr, Sr/Y La/Yb and, low Y and Yb contents. The major and trace element contents of the Jindong granitoids fall well within the adakitic field, whereas other Cretaceous granites in the same basin are plotted in the island arc ADR area in discrimination diagrams. Chondrite normalized REE patterns show generally enriced LREEs (La/Yb)C = 3.6-13.8) and slight negative to flat Eu anomalies. The mean Rb-Sr whole rock isotopic age of the Jindong granitoids is $114.6{\pm}9.1$ Ma with an initial Sr isotope ratio of 0.70457. These values suggest that the magma has mantle signature and intruded into the area during Early Cretaceous. The Jindong granitoids have similar paleogeographical locations, paleotectonic environments and intrusion ages to those of the Shiraishino granodiorites of Kyushu Island and the Tamba granitoids of San'yo belt located on southwestern Japanese arc.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.5
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• pp.1135-1146
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• 2015

This thesis aims to improve the safety of bicycle traffic for activating the use of bicycle, main means of non-powered and non-carbon transportation in order to cope with worldwide crisis such as climate change and energy depletion and to implement sustainable traffic system. In this regard, I analyzed the problem of bicycle roads currently installed and operated, and developed the bicycle accident forecasting model. Following are the processes for this. First, this study presented the current status of bicycle road in Korea as well as accident data, collect the data on bicycle traffic accidents generated throughout the country for recent 3 years (2009~2011) and analyzed the features of bicycle traffic accidents based on the data. Second, this study selected the variable affecting the number of bicycle accidents through accident feature analysis of bicycle accidents at Jeollanam-do, and developed accident forecast model using the multiple regression analysis of 'SPSS Statistics 21'. At this time, the number of accidents due to extension per road types (crossing, crosswalk, other single road) was used. To verify the accident forecast model deduced, this study used the data on bicycle accident generated in Gwangju, 2011, and compared the prediction value with actual number of accidents. As a result, it was found out that reliability of accident forecast model was secured through reconciling with actual number of cases except certain data. Third, this study carried out field survey on the bicycle road as well as questionnaire on satisfaction of bicycle road and use of bicycle for analysis of bicycle road problems, and presented safety improvement measures for the problems deduced as well as bicycle activation plans. This study is considered to serve as the fundamental data for planning and reorganizing of bicycle road in the future, and expected to improve safety of bicycle users and to promote activation of bicycle use as the means of transportation.

• Research in Plant Disease
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• v.24 no.2
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• pp.153-161
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• 2018

We selected eight resistant cultivars including 'Heukryongsamcheok', 'Heukgeumsolsamcheok' and 'Gangryeoksamcheok' showing high suppressive effect against cucumber downy mildew (CDM) through plastic film house and field trials in spring and autumn season in 2015. Of them, these three varieties, 'Heukryongsamcheok', 'Heukgeumsolsamcheok' and 'Gangryeoksamcheok' were used to evaluated suppressive effect against CDM by comparing disease severity (area under disease development progress curve, AUDPC) with those of three susceptible varieties under plastic film house condition. AUDPC of three resistant cultivars was in the range of 10.9 to 23.6, meanwhile those of three susceptible cultivars was in the range of 286.7 to 290.3. Consequently, we confirmed that cultivation of the selected resistant cultivars can reduce CDM in vivo. When disease severity (diseased leaf area) was investigated on a resistant cultivar ('Heukryongsamcheok') sprayed without any organic materials and susceptible cultivars sprayed single-, two times- and three times with Bordeaux mixture, sulfur-loess mixture and $Kocide^R$ (copper hydroxide), respectively, it was the lowest in the resistant cultivar plot compared to susceptible cultivar plots sprayed with any organic materials. In addition, we evaluated control effect of the selected resistant cultivar by comparing that of organic materials including lime sulfur mixture, Bordeaux mixture and garlic extract. As a result, Bordeaux mixture showed the highest control effect against CDM. AUDPC of Bordeaux mixture, resistant cultivar, lime sulfur, garlic extract and untreated control was 3.9, 10.6, 95.6, 24.9, and 258.7, respectively. Based on the above-mentioned results, we think that the resistant cultivars and Bordeaux mixture can be effectively used to control CDM as one of control measures under the farmhouse condition.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.260-270
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• 2011

This study was carried out to examine the effect of rice bran, barley bran, burned rice bran, and burned barley bran on the growth and yield of Chinese chive (Allium tuberosum Rottler), taro (Colocasia esculenta), and weed control. When the above 4 brans were examined 13, 27, 41 and 57 days respectively after application, the plant height of Chinese chive applied with burned barley bran was significantly higher than non-treated control, whereas the other brans did not have any distinct effect on the plant height or population number of Chinese chive. However, when examined 57 days after the application of the above 4 brans, all the plants applied with brans showed more than twice the improvement in shoot fresh weight compared with non-treated control. A chemical analysis of soil 57 days after the application of the above 4 brans showed that the soils were richer in available phosphate and organic matter. Shoot fresh weight of Chinese chive at 2 weeks after cutting was significantly higher in barely bran treated plot than in non-treated plot. In the case of taro, only taro plots transplanted when 10 cm tall and applied with barley bran showed an improvement in growth increment of both the underground and above parts. However, when sowed seeds after the application of the 4 brans, the yield of taro was reduced by the brans. Thus this research indicates that the effect of brans is differ based on the amount of bran application as well as crops. The effect of weed control on Echinochloa crus-galli, Digitaria clliaris, Chenopodium album, and Solanum nigrum as affected by brans was very low in pot conditions. Weed efficacy of the brans was also very low in field conditions. Growth of Chinese cabbage and garland chrysanthemum was inhibited 63% and 37% by rice bran at $4,000kg\;ha^{-1}$, respectively, but other crops such as maize, squash, cucumber, and Chinese chive were inhibited by 0-20%. These results were similar to that of barley bran except for Chinese cabbage.