• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.41-41
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• 2015

BSA-seq technologies, combined Bulked Segregant Analysis (BSA) and Next-Generation Sequencing (NGS), are making it faster and more efficient to establish the association of agronomic traits with molecular markers or candidate genes, which is the requirement for marker-assisted selection in molecular breeding. Clubroot disease, caused by Plasmodiophora brassicae, is a serious threat to Brassica crops. Even we have breed new clubroot resistant varieties of Chinese cabbage (B. rapa ssp. pekinesis), the underlying genetic mechanism is unclear. In this study, an $F_2$ population of 340 plants were inoculated with P. brassicae from Xinye (Pathotype 2 on the differentials of Williams). Resistance phenotype segregation ratio for the populations fit a 3:1 (R:S) segregation model, consistent with a single dominant gene model. Super-BSA, using re-sequencing the parents, extremely R and S DNA pools with each 50 plants, revealed 3 potential candidate regions on the chromosome A03, with the most significant region falling between 24.30 Mb and 24.75 Mb. A linkage map with 31 markers in this region was constructed with several closely linked markers identified. A Major QTL for clubroot resistance, CRq, which was identified with the peak LOD score at 169.3, explaining 89.9% of the phenotypic variation. And we developed a new co-segregated InDel marker BrQ-2. Joint BSA-seq and traditional QTL analysis delimited CRq to an 250 kb genomic region, where four TIR-NBS-LRR genes (Bra019409, Bra019410, Bra019412 and Bra019413) clustered. The CR gene CRq and closely linked markers will be highly useful for breeding new resistant Chinese cabbage cultivars.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.669-684
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• 2013

This study was investigated to evaluate the effects of biodiversity and pest insect occurrence by soil surface management methods such as green manure crop, grass planting and clean-tilled crops on persimmon orchards. Green manure crop pests was investigated 7 species including Hypera postica, Laodephax striatellus, Megoura crassicauda, Aphis craccivora, Nephotettix cincticeps, Liriomyza sp., black spot and the most dangerous pest was H. postica but it did not damaged persimmon tree. Amount of pests and natural enemies dwelling soil covering plant was not difference between organic farming (hairy vetch planting) and conventional farming (natural weed). Homona magnanima occurred three times a year but it rarely damaged leaf of persimmon. Total adult moth catched by pheromone trap was 1,261 organic farm, 1,003 conventional farm and 621 clean-tilled farm. Grapholita molesta occurred four times a year but it also rarely damaged twig of persimmon. Number of collected invertebrate species and individuals on soil sample was follow as : 838 individuals of 22 species at organic farm, 421 individuals of 17 species at conventional farm and 381 individuals of 15 species at clean-tilled farm. The richness index was lined up by organic farm 3.12> conventional farm 2.65> clean-tilled farm 2.36.

• Korean Journal of Organic Agriculture
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• v.21 no.4
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• pp.753-767
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• 2013

Soil contamination has continuously increased worldwide, thus the remediation for the contaminated soils has risen steadily. However, the consideration of ecological safety for the remediated soils and their agricultural uses has been very limited. Therefore, this study was to investigate the influences of selected environmentally-friendly agricultural materials, organic by-product fertilizer (OF), charcoal (CC), and biochar (BC), as soil conditioners for improving poor chemical properties of fuel-oil removed soil by land farming technique. Two different remediated soils, remediated soil A (RSA) and remediated soil B (RSB), were selected. Soil texture of both RSA and RSB was sandy loam. The chemical properties of RSA and RSB were as follows: soil pHs of 8.5 and 8.7, soil organic matter contents of 7.4 and 5.5g $kg^{-1}$, total nitrogen contents of 0.26 and 0.10g $kg^{-1}$, available phosphorus concentrations of 7.2 and 4.4mg $kg^{-1}$, and exchangeable calcium concentrations of 14.8 and $11.7cmol_c$ $kg^{-1}$, respectively. Results of the properties were not reached for the optimal values for cultivating crops that were recommended by National Academy of Agricultural Science at Rural Development Administration in Korea. However, after applying OF, CC, and BC, the chemical properties of soils were selectively improved, which were that soil organic matter content and available phosphorus concentration increased, whereas the soil pH were not changed. In particular, the chemical properties were positively changed more with the application of 5.0% biochar. Thus, continuous management of the remediated soils with applying the eco-friendly agricultural materials can improve the quality of reme-diated soils.

• The Korean Journal of Elementary Counseling
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• v.11 no.2
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• pp.279-298
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• 2012

The purpose of this study was to explore the different perceptions of relationship with significant others of multicultural children with PTSD symptoms. To select the subjects for this study, Korean version of Greenwald and Rubin's CROPS(Child Report of Post-traumatic Symptoms) was administered to 97 multicultural children and 110 Korean children. Among them 20 multicultural children and 22 Korean children were determined as children with PTSD symptoms. SCT was administrated to 42 children and the content analysis of 42 SCTs was undertaken. The following results are the major findings of this research: a) multicultural children perceived their mothers, fathers, friends, and teachers more negatively than Korean children; b) only 55% of multicultural children had positive self-images while almost Korean children had positive self-images; c) multicultural children expressed psychological trauma from peers in school while Korean children expressed psychological trauma from parents at home. Lastly, we discussed implications of the results, limitations and suggestions for future study.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.3
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• pp.354-362
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• 2018

Objective: Wheat is an alternative to corn silage for ruminant feeding in northern China. This study examined the effects of harvest time and added molasses on nutritional content, ensiling characteristics and in vitro degradation of whole crop wheat (WCW). Methods: Fresh WCW at the milk-ripe stage was harvested at 0700 h (i.e., in the morning [Mo]) and 1700 h (i.e., in the afternoon [Af]), and then immediately used to prepare silage and make hay. Commercial molasses was added to Af WCW at 0%, 2%, 4%, and 6% (fresh weight) proportions. The WCW treated with molasses was mixed thoroughly prior to ensiling. Results: Dry matter (DM), neutral detergent fiber, water soluble carbohydrate (WSC) content (p<0.01), accumulative gas production in 72 h ($GP_{72h}$, 77.46 mL/g vs 95.15 mL/g) and dry matter disappearance in vitro (69.15% vs 76.77%) were lower (p<0.05), while crude protein (CP) content was higher for WCW silage (WCWS) compared to WCW (p<0.01). The propionic acid and butyric acid concentrations in WCWS from Mo WCW were 1.47% and 0.26%, respectively. However, the propionic and butyric acid concentrations were negligible, while the ammonia nitrogen/total nitrogen ($NH_3-N/TN$, p<0.01) concentration was lower and the rate of gas production at 50% of the maximum (17.05 mL/h vs 13.94 mL/h, p<0.05) was higher for Af WCWS compared to Mo WCWS. The incubation fluid's $NH_3-N$ concentration was lower in WCWS and Af WCW compared to Mo WCW (p<0.05). The CP and WSC content increased with increasing molasses levels (p<0.05). Furthermore, the pH (p<0.01) and time when gas production was 50% of the maximum (2.78 h vs 3.05 h, p<0.05) were lower in silage treated with 4% molasses than silage without molasses. Conclusion: Harvesting wheat crops in the afternoon and adding molasses at 4% level to WCW optimally improved ensiling characteristics, leading to well-preserved silage.

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.65-66
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• 2004

There have been groves, in many cases, along with hedgerows and remnant forests around a traditional Korean village. A village grove is very closely connected to the life of residents. Sometimes it was a holy place where important village festivals were held, and became a resting place for farmers, especially in sunny summer. As a matter of fact, it is noted that traditional Korean village groves had been fostered for many purpose as religion, Confucianism, scenery, sanitation, traffic guard, public security, agriculture, hunting, and military and public uses were included in Chosun Govemor General(1938). Village groves were usually located at the outlet of watershed inside which a village was built. In addition, village groves used to be established along part of mountain ranges, streams and streets. A unique type of village grove, called bibosoop was fostered especially where the outlet of watershed was largely opened. In other cases, it was placed where a part of mountain range was relatively low, or where village residents were likely to see ugly objects such as a huge cliff, stony upland with an unvegetated area and the like(Kim and Jang 1994). In a sense, a sheltebelt is a sort of bibosoop as it is a landscape element to complement places that are exposed to strong winds. However, it is comparable to other typical bibosoop that is situated at a topographically very specific zone of watershed. In this paper, we will address potential functions of Korean village groves from a perspective of modern landscape ecology and show current status of some remnants, based on preliminary surveys. A village grove functions as barrier or filter of objects such as water, nutrients, and other elements and habitat of wildlife (park et al. 2003, Lee 2004). The village grove slows down the flow of water and air, maintains soil moisture an hinders soil erosion, enabling cultivation of crops and bringing up creatures nearby. It contributes to enhancing biodiversity. Birds rest on shrubby and woody trees of the element. Presumably, other organisms may also inhabit the village groves and take advantage of it when those move from a forest patch to others. Emerging insects acclimate themselves in the shade of the green space before they fly to sunny air. Besides the village grove acts as a component of agroforestry system as leaf litter is shed from a grove to an asjacent agricultural area, and transformed into green manure(Lee 2004). By the way, many of the landscape elements were destroyed or declined in Koea during the past several decades. The losses have been parallel or linked to environmental degradation. Unfortunately, we have a little reliable data as for how many groves have disappeared in Korea until now. There has been no complete census on the village groves in Korea, and the viewpoints of survey were to a degree different depending on surveyors. So, it is difficult to analyze the temporal and spatial change of village groves. Currently, national inventory data of Korean village groves are available in three reports. We reviewed the locations of village groves and arranged those according to the present administrative units, DONG. With the limited data, we found that at least 484 of village groves were recorded in South Korea. Among all provinces, village groves were most in Gyeongsanbuk-Do Province and least in Chungcheongbuk-Do Province(Table 1). This is a preliminary report prepared while some quantitative data regarding functions and lossers of the village groves are being collected. More detailed data will be introduced in the near future.

• Journal of Plant Biotechnology
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• v.42 no.4
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• pp.290-297
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• 2015

Based on the place of its origin, pear tree (Pyrus spp.) is largely divided into European pears (P. communis, cultivated mainly in Europe and the U.S.) and Asian pears (P. pyrifolia, P. bretschneideri, and P. ussuriensis, distributed and grown in East Asian countries including China, Japan, and Korea). Most pear trees have 17 chromosomes (diploidy, 2n=2x=34). Their genetic studies and precise cultivar breeding are highly restricted by conditions such as self-incompatibility controlled by S-locus and juvenility as one major character of fruit crops. Genetic studies on Pyrus have been promoted by the development of various molecular markers. These markers are being utilized actively in various genetic studies, including genetic relationship analysis, genetic mapping, and QTL analysis. In addition, research on pear genetic linkage maps has been extended to studies for the identification of QTL for target traits such as disease resistance and genetic loci of useful traits. NGS technology has radically reduced sequencing expenses based on massive parallel reactions to enable high-capacity and high-efficiency. NGS based genome analyses have been completed for Chinese pear 'Danshansuli' and European pear 'Bartlett'. In Korea, GWAS for agricultural valuable traits such as floral structure, ripening, and total soluble contents have been conducted through resequencing. GBS has been performed for 'Whangkeumbae', 'Cheongsilri', and 'Minibae'.

• Journal of Bio-Environment Control
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• v.22 no.3
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• pp.234-240
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• 2013

The purpose of this study was to provide basic data used in greenhouse design, and for this purpose, the crop loads of tomato and paprika which have high crop load among crops cultivated in greenhouse were measured. The maximum differences in lowest and mean temperatures between cultivation year and normal years for winter season were -5.6 and $-4.9^{\circ}C$, respectively and those for summer season were 3.0 and $1.5^{\circ}C$, respectively. The calibration of push & pull gauge indicated approximate 0.99 of coefficient of determination, representing very high association. The planting densities of paprika and tomato were 3.43, 3.56 and $2.13plants{\cdot}m^{-2}$, respectively. The yields were 4.1, 4.3 and $16.2kg{\cdot}plant^{-1}$, corresponding to 14.1, 15.2 and $34.5kg{\cdot}m^{-2}$ of yield per unit area. The maximum loads were 1.3, 1.5 and $3.3kg{\cdot}plant^{-1}$, respectively. When the paprika were hanged on cross beam, the total crop load applied to it was estimated to be $15.3{\sim}15.9kg{\cdot}m^{-2}$, and when the weights of gutters supporting the cultivation beds, the total weights were $26.0{\sim}26.9kg{\cdot}m^{-2}$.

• Journal of Distribution Research
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• v.15 no.2
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• pp.35-70
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• 2010

In this study, we examined distribution channel relationship by using the idea of Cheong, which is a unique feeling an positive role in Korean society. Companies make great efforts to maintain long-term relationship with buyers. Understanding distinctive relationship system of each culture should precede these efforts to bring effective results. So we considered how Cheong, a meaningful factor in Korean distribution channel, affects relationship quality and performance. As a result of research analysis from 272 survey questionnaires of retailers, engaging in Crops Protected Material industry in Korea, supplier's idiosyncratic investment, retailer's Cheong, and dependence of retailers on suppliers have positive effects on relationship quality. Supplier's idiosyncratic investment and cognitive factors have the highest influence and Cheong, an emotional factor, follows. Dependence, a motivational factor has the least influence. We confirmed that retailer's cooperation and long-term orientation are directly influenced by retailer's commitment. Active cooperation of the retailer, a partner of a distribution channel, is regarded as an essential factor for supplier's effective business. Retailer's commitment increased that cooperation. Retailer's trust and commitment also decreased relationship conflicts. The results of this study imply that companies should increase idiosyncratic investment to improve relationship quality. But increasing idiosyncratic investment is limited because it requires monetary investment. Therefore companies need to recognize the importance of Cheong, revealed as a new factor, improving relationship quality and to make the best use of it. In this study, we contributed theoretically by examining the role of Cheong, and introducing its distribution discipline. We also make practical suggestions about supplier's relationship management.

• Journal of Radiation Protection and Research
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• v.13 no.1
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• pp.8-20
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• 1988

The annual individual and collective doses to the thyroids of four age-dependent groups due to the in-take of I-131 released from the Younggwang nuclear power plant NU-1 & 2, Korea, are estimated using the model presented in ICRP 29. Sensitivity and robustness of the model are analyzed. In case of 0.12% fuel defect during normal operation, the collective dose is founded to be 3.05${\times}10^{-3}$man-thyroid-Sv, which is higher than the value calculated by the GASPAR code, 2.3${\times}10^{-3}$man-thyroid-Sv. The maximal individual annual doses resulting from an acute release are higher than those calculated under the assumption of continuous release by $1.4{\sim}1.7$ times. The most important pathway to the infant is milk and, in contrast, that to child, teen and adult is ingestion of crops. The model used is the calculation appears to be influenced by the variables such as roubstness-index. The weighted committed dose equivalent obtained by the ICRP 29 model is slightly higher than that calculated by the three-compartment model.