• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.21-21
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• 2017

Severe lodging has recurrently occurred at strong typhoon's hitting in recent climate change. The identification of quantitative trait loci (QTLs) and their responsible genes associated with a strong culm and their pyramiding are important for developing high-yielding varieties with a superior lodging resistance. To identify QTLs for lodging resistance, the tropical japonica line, Chugoku 117 and the improved indica variety, Habataki were selected as the donor parent, as these had thick and strong culms compared with the temperate japonica varieties in Japan such as Koshihikari. By using chromosome segment substitution lines (CSSLs) in which chromosome segments from the japonica variety were replaced to them from Habataki, we identified the QTLs for strong culm on chrs. 1 and 6, which were designated as STRONG CULM1 (SCM1) and STRONG CULM2 (SCM2), respectively. By using recombinant inbred lines (BILs) derived from a cross between Chugoku 117 and Koshihikari and introgression lines, we also identified the other QTLs for strong culm on chrs. 3 and 2, which were designated as STRONG CULM3 (SCM3) and STRONG CULM4 (SCM4), respectively. Candidate region of SCM1 includes Gn1 related to grain number. SCM2 was identical to APO1, a gene related to the control of panicle branch number, and SCM3 was identical to FC1, a strigolactone signaling associated gene, by performing fine mapping and positional cloning of these genes. To evaluate the effects of SCM1~SCM4 on lodging resistance, the Koshihiakri near isogenic line (NIL) with the introgressed SCM1 or SCM2 locus of Habataki (NIL-SCM1, NIL-SCM2) and the another Koshihikari NIL with the introgeressed SCM3 or SCM4 locus of Chugoku 117 (NIL-SCM3, NIL-SCM4) were developed. Then, we developed the pyramiding lines with double or triple combinations derived from step-by-step crosses among NIL-SCM1 NIL-SCM4. Triple pyramiding lines (NIL-SCM1+2+3, ~ NIL-SCM1+3+4) showed the largest culm diameter and the highest culm strength among the combinations and increased spikelet number due to the pleiotropic effects of these genes. Pyramiding of strong culm genes resulted in much increased culm thickness, culm strength and spikelet number due to their additive effect. SCM1 mainly contributed to enhance their pyramiding effect. These results in this study suggest the importance of identifying the combinations of superior alleles of strong culm genes among natural variation and pyramiding these genes for improving high-yielding varieties with a superior lodging resistance.

• Proceedings of the Korea Contents Association Conference
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• 2005.05a
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• pp.36-50
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• 2005

e-Learning has been mushrooming with wide range of learning groups from pedagogy to andragogy. Despite of increasing e-learning opportunities, many people doubt whether e-learning learners really learn something. The related research papers emphasized that e-Learning would be a failure in terms of understanding of e-learners and intuitive learning activities for activating learner's long-term memory span. The current learning strategies in e-Learning may be based on the traditional classroom, and this results in boring and ineffective learning outcomes. This paper analyzed that how learners have received e-Learning for the last few years from the research and explained what could be the failing aspects of e-Learning. To be successful, e-Learning should consider the e-Learner's individualized teaming style and thinking patterns. When considering of various e-Learning components, the quality of e-learning should not be focused on any specific single factor, but develop every individual factor to the high level of quality. In conclusion, this paper suggest that we need new understand of e-Learning and e-Learner. Also the e-Learning strategies should be examined throughly whether they are on the side of learners and realized how they learn from e-Learning. Finally, we should add enormous imagination into e-Learning for next generation because their teaming patterns significantly differ from their parent's generation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.208-214
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• 1987

A genetic study on the panicle characters in Oryza sativa was carried out by means of a 5 x 5 diallel cross. The five parental varieties were Raekyung, Yeongnamjosaeng, Nongbaek, Yushin and Honenwase. All characters were correlated positively each other, except number of kernels per primary branch. The number of secondary branches per primary branch.was the most effective factor in determining the number of kernels per panicle, the next being the number of primary branches per panicle. Regression analyses of the data of Vr/Wr indicated the presence of non-allelic gene interactions for all characters. Overdominant characters were the number of kernels per panicle, the number of primary branches per panicle, the number of secondary branches per primary branch, the number of kernels per primary branch and sum of kernels on all the tertiary branches per panicle, suggesting that the characters were more influenced by dominant effect than additive effect. However, the number of kernels per secondary branch was partially dominant where the genetic variation was due more to additive effect than to dominance effect. But after omitting the parent which had non-allelic interaction gene, the characters; the number of kernels per panicle, the number of secondary branches per primary branch, and the number of kernels per secondary branch, were partially dominant. Narrow sense heritabilities(h$^2$ N) in number of kernels per panicle and number of secondary branches were high and moderate, respectively, but those of the rest were lower. Mean squares of GCA and SCA of all characters, except SCA of the number of kernels per secondary branch, were highly significant. Effects of GCA were larger than SCA effects in all characters. Raekyung, Yushin and Nongbaek had highly positive GCA, and the best positive SCA was observed in crosses of Nongbaek x Tongillines (Raekyung, Yushin, and Yeongnamjosaeng) in all characters.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.269-276
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• 2008

Field resistance is defined as the resistance that allows effective control of a parasite under natural field condition and is durable when exposed to new races of that parasite. To identify the genes for field resistance to rice blast, quantitative trait loci (QTLs) conferring the resistance for races and blast nursery screening in japonica rice cultivars were detected and mapped using SSR markers. QTL analysis was carried out in 190 RILs population from the cross between Suweon365 (moderately resistant) and Chucheong (highly susceptible). Twelve QTLs against nine blast races inoculated were detected on chromosomes 1, 2, 4, 6, 7, 11 and 12. They explained from 5.1% to 34.9% of total phenotypic variation. Eight QTLs against blast nursery screening in four regions for three years were detected on chromosomes 1, 2, 4, 11 and 12. The phenotypic variation explained by each QTL ranged from 4.3% to 37.7%. Three chromosome segment substitution lines (CSSLs) of $BC_2F_6$ by backcross method were developed to transfer the QTLs into the susceptible cultivar Chucheong as a recurrent parent. A CSSL4-1 containing two QTLs qLB6.2 and qLB7 against blast races showed to the reaction of 6 to 7 at blast nursery in two regions for two years. The CSSL4-2 and CSSL93 containing QTLs, qLB11.2 and qLB12.1 of the resistance against leaf blast in blast nursery screening, respectively, had enhanced the resistance for blast nursery screening across two regions and in two years.

• Korean Journal of Plant Resources
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• v.20 no.4
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• pp.298-303
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• 2007

To examine taxonomic relationships among 24 leaf mustard allies (Brassica juncea) derived from domestic collections and introduced species, principal component analysis (PCA) and cluster analysis on 16 morphological characters were carried out. Of 16 characters, total fresh weight, total dry weight, shoot fresh weight and leaf length were useful characters for the understanding of taxonomic relationships among them. Cluster analysis using scores of the principal components indicated that 24 leaf mustards could be grouped into domestic collections and introduced species at 1.0 of average distance in UPGMA. Moreover, in experiment of $F_{1}$ recombination test, heterosis appeared greatly in Sanchiohbachirimen takana A ${\times}$ Akaohba takana, Goheung namyang ${\times}$ Sanchiohbachirimen takana B, and Goheung namyang ${\times}$ Akaohba takana cross combinations. Sanchiohbachirimen takana A and Akaohba takana have a high parent combining ability for breeding cultivars using cytoplasmic male sterility.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.467-480
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• 2018

The purpose of this study was to investigate gender difference of community-residing elderly's life satisfaction and influential factors. Data were collected from 461 elders aged 60+ with the cooperation of several social service center for the aged, senior centers, and senior citizen associations in Daejeon Metropolitan City and Chungcheongnam-do(Cheonan-si and Okcheon-gun). SPSS 22.0 software was used for t-test and cross tabulation analysis, correlation analysis, and hierarchical regression analysis. The results showed there was statistically significant difference of elderly's life satisfaction by gender in multivariate analysis including sociodemographic factors, social network and relationship with children variables, but no difference in bivariate analysis. There was also significant difference in the factors affecting community-residing elderly's life satisfaction by gender. A few factors like friend support, number of regular social gatherings, and subjective health status were statistically significant in predicting male elderly's life satisfaction. Predictors of female elderly's life satisfaction which were perceived elderly parent-children conflict, friend support, monthly income, subjective health status, support to children, support from children were more diverse, compared to the predictors for male elderly's life satisfaction. Based on the findings, suggestions for social welfare policy and practice to improve community-residing elderly's life satisfaction considering the gender difference were discussed.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.552-561
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• 2019

In korea, debris-flow disasters are induced by typhoon and localized torrential rainfall annually. These disasters are particularly severe in the Korean national park due to its geomorphological characteristics. This study was conducted to analyze the landslide characteristics and forest environmental factors of landslide areas located in rugged mountain range in the Korean national park (Mt. Seorak, Mt. Jiri, and Mt. Sobaek). Overall, landslides occurred at 474 sites. The average area of the landslide scar among these sites was 1,212 ㎡. The average landslide sediment was 1,389 ㎥, average landslide length was 75 m, and the average width was 12.9 m. The landslides frequently occurred in regions with igneous rock and coniferous forest. In addition, slope gradient degree (31°-40°), slope gradient direction (N), vertical slope (concave), cross slope (concave), altitude (401-800 m), position (middle), stream order (first order), forest type (mixed), parent rock (igneous), and soil depth (<46 cm). The relationship between landslide soil volume and environmental factors showed positive correlation. The variables of vertical slope (complex), altitude (<1,201 m), and soil depth (<46 cm) correlated significantly at 1 % level.

• Horticultural Science & Technology
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• v.33 no.5
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• pp.789-795
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• 2015

The new garden chrysanthemum (Dendranthema grandiflorum Ramat.) cultivar 'Nuri Ball' was developed at Yesan Chrysanthemum Experiment Station of Chungcheongnam-do Agricultural Research and Extension Services in 2011. 'Nuri Ball' was bred through a cross between the '02-145-01' line as the female parent with yellow flower color and '02-04-32' as the male plant with white flower color in 2004. Three years of adaptation trials were conducted from 2006 to 2009 under natural conditions. This study compared the external shape type with that of 'White Miri' and conducted ploidy and RAPD (Random amplified polymorphic DNA) marker analyses. These tests showed that 'Nuri Ball' cultivar has its own characteristics compared with the control 'White Miri'. 'Nuri Ball' was a shrub type variety with semi-double flowers of 4.0 cm in width with white petals. It could produce 1025.2 flowers per plant in autumn. Compared with the control 'White Miri', 'Nuri Ball' was similar in terms of shape and color of flowers, but was different in flower size and number. The natural flowering time of 'Nuri Ball' was late September. It had very vigorous growth and an early budding plant. 'Nuri Ball' was demonstrated to be a new cultivar based on ploidy test and RAPD analysis. 'Nuri Ball' is intended for use as a bed chrysanthemum and expected to contribute to farm incomes in landscaping.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.320-323
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• 2009

A new grafting cactus 'Yeomyeong' was developed by an interspecific crossing between Gymnocalycium marsoneri and G mihanovichii at the National Institute of Horticultural and Herbal Science, Rural Development Administration in 2005. In 2001, an interspecific crossing line '9922012' with orange color was selected from the cross of G. marsoneri ${\times}$ G. mihanovichii 'IG-112'. The line '9922012' as a female parent was crossed with G. mihanovichii 'IG-177', and the orange colored lines were obtained in 2002. The 'Wonkyo G1-159' was selected from the orange colored lines through three times of characteristic evaluation during 2003 to 2005. The 'Wonkyo G1-1 59' was named 'Yeomyeong' in the RDA in 2005. The color of both body and tubercle was orange. The shape of globe was flattened round and it had 7 to 9 ribs. The spine was erect, short sized and grayish brown color. Growth was faster, reaching 41.8-47.7 mm in diameter, than the comparison cultivar 'Hwangwol', at 10 months after planting. The number of tubercle was 6.9-12 per globe. 'Yeomyeong' was developed for export to the America and the Netherlands. Characteristics of the cultivar could be maintained by grafting on the Hylocereus trigomus.

• Journal of agriculture & life science
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• v.43 no.5
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• pp.39-42
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• 2009

Soybean is an important sources of plant proteins for human and animal nutrition. The use of soybean proteins has been expanded in the food industry due to their excellent nutritional benefits. But, Soybeans contain allergenic proteins that cause allergies to sensitive individuals. ${\beta}$-conglycinin(7S globulin) and glycinin(11S globulin) are the major components of storage protein in soybean. ${\beta}$-conglycinin consists of three subunits, ${\alpha}^{\prime}$, ${\alpha}$, ${\beta}$ and exhibits poorer nutritional and food processing properties than glycinin. There is a great deal of interest in the development of soybean lines with reduced amounts of ${\beta}$-conglycinin. The objective of this study was to determine the inheritance of ${\alpha}^{\prime}$-subunit protein in 7S globulin. F2 population was developed from the cross of "Jinpumkong2ho"(${\alpha}^{\prime}$-subunit presence) and PI506876(${\alpha}^{\prime}$-subunit absence) parent. Total 98 of F2 seeds were obtained and analyzed for the segregation of ${\alpha}^{\prime}$-subunit protein by SDS-PAGE. Among 98 F2 seeds, 70 F2 seeds showed ${\alpha}^{\prime}$-subunit protein and 28 F2 seeds did not show ${\alpha}^{\prime}$-subunit protein. The segregation ratios of 3 : 1 for presence and absence of ${\alpha}^{\prime}$-subunit protein were observed(${\chi}^2=0.667$, P=0.414). These data indicate that presence and absence of ${\alpha}^{\prime}$-subunit protein is controlled by a single major gene and might be useful for strain selection of 7S protein reduced soybean.