• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.3
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• pp.233-238
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• 1981

This trial was conducted to find out some tendencies in variations of grain chalkiness according to their position on a panicle. To know the varietal character in variations of chalkiness and their relations with grain weight, distribution of chalkiness in bulk seed was observed for four varieties. Milyang 23, relatively clear variety and SR601-25-1, much chalky variety were checked for the grain chalkiness in their positions on the panicle. The results obtained are summerized as follows: Rice chalkinss were varied in degree from 0 (clear) to 9 (chalky) within a variety. Large number of grains were distributed to clear for clear variety and to chalky for chalky variety, but almost equal number of grains were distributed to all degree of chalkiness for intermediate chalky variety. For the relationship between degree of chalkiness and grain weight, chalky grains founded in clear variety and clear grains founded in chalky variety decreased in weight, while in intermediate chalky varieties both grains of clear and chalky decreased. There were great varietions in grain chalkiness on a panicle for both clear and chalky varieties. There was no definite trend in distribution of chalkiness except that the first primary branch and terminal grains in every primary branch showed clear in Milyang 23. Mean degree of grain chalkiness was relatively high in grains of middle part of panicle only from Milyang 23.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.289-295
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• 2006

This study was carried out to evaluate the suitability of simple sequence repeat (SSR) markers for varietal identification and genetic diversity in 28 commercial tomato varieties. The relationship between marker genotypes and 28 varieties was analyzed. Of the 219 pairs of SSR primers screened against ten tomato varieties, 18 pairs were highly polymorphic with polymorphism information content (PIC) ranging from 0.467 to 0.800. Among the polymorphic loci, two to nine SSR alleles were detected for each locus with an average of 3.3 alleles per locus. Genetic distances were estimated according to Jaccard's methods based on the probability that the amplified fragment from one genotype would be present in another genotype. These varieties were categorized into cherry and classic fruit groups corresponding to varietal types and genetic distance of cluster ranging from 0.35 to 0.97. The phonogram discriminated all varieties by marker genotypes. The SSR markers proved to be useful variety identification and genetic resource analysis of tomato.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.163-168
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• 2001

"Hwasan 103" is a new cold-tolerant Italian ryegrass(Lo1ium multiflorum L.) variety developed by theNational Livestock Research Institute(NLR1) in 1999. To develop a cold-tolerant variety of Italianryegrass(Lo1ium multiflorum L.), cold-tolerant clones survived under - 13 - - 14$^{\circ}$C of minimum average airtemperature(MAAT) in January were selected at Hwachun, Kwangwon Province in 1995. Five clones ofselected clones were polycrossed for seed production by NLRI, RDA in 1996."Hwasan 103" was diploid variety, green in leaf color and broad in flag leaf width. Also it hassemi-prostrate and medium growth habit in late autumn and in early spring, respectively. "Hwasan 103" wasexcellent in lodging tolerance at harvesting time. First heading date of "Hwasan 103" was 14th May, it wassimilar to that of Marshall. Expecially, "Hwasan 103" survived about 50-70% under - 10- - 12'C ofMAAT in January, so it could be cold-tolerant variety that can be safely cultivated in regions higher than -9$^{\circ}$C of MAAT in January. Compared with Marshall "Hwasan 103" showed 3% higher fresh yield (57.8MTper ha) and it showed 2% higher dry matter yield (11.OMT per ha). Higher IVDMD and TDN and lowerADF and NDF were observed in "Hwasan 103" than those of Florida 80 and Marshall in Forage quality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 103")all in Forage quality.(Key words : Italian ryegrass, Cold tolerance, New variety "Hwasan 103")n 103&")ot;)

• Journal of Life Science
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• v.17 no.5 s.85
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• pp.619-624
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• 2007

Species of genus Acanthopanax(Araliaceae) are long-lived trees primarily distributed throughout East Asia. These species are regarded as medically and ecologically important in Korea. A variety of Cheongsong in Korea is one of these cultivated varieties, however this variety is much longer(>100 years) than those of other cultivated groups. The components of variety of Acanthopanax in Cheongsong were analyzed for the first time and were compared to those of all Acanthopanax taxa in Korea. Nineteen components were specific to variety in Cheongsong. The main components of this variety were $\beta$-caryophyllene, hexadecanoic acid and ethyl stearate. Although some components are differ from each other, variety Cheongsong was similar to A. senticosus at phonetic topology with content of the chemicals, In addition, six species of genus Acanthopanax were investigated to compare the major chemical components by GC-MS.

• Korean Journal of Breeding Science
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• v.43 no.1
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• pp.1-13
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• 2011

Low temperature stress is one of the major negative factors affecting vegetative and reproductive growth of rice. To better understand responses of rice plants to low temperature we analyzed transcriptome expression patterns in glumous flower of cold-tolerant japonica rice variety, Stejaree45, and cold-susceptible variety, HR19621-AC6 at booting stage under cold water irrigation. A total of 2,411 probes were differentially expressed by low temperature in glumous flowers of the two varieties. Some important genes involved in hormone biosynthesis showed variety-specific regulation. Expression of GA20ox3 and GA2ox, among the genes involved in GA biosynthesis, was regulated differentially in the two varieties. Among the genes involved in IAA biosynthesis, YUCCA1 and TAA1:1 showed variety-specific regulation. Among the genes involved in cytokinin biosynthsis and signaling, expression of LOG, HK1 and HK3 was significantly down-regulated only in the cold-susceptible variety. Among the genes involved in ABA biosynthesis, NSY and AAO3 were down-regulated only in the cold-tolerant variety. In general, genes involved in GA, IAA and cytokinin biosynthesis responded to cold temperature in such a way that capacity of those bioactive hormones is maintained at relatively higher levels under cold temperature in the cold-tolerant variety, which can help minimize cold stress imposed to developing reproductive organs in the cold-tolerant variety.

• Korean Journal of Breeding Science
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• v.43 no.4
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• pp.322-329
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• 2011

Microsatellite markers were utilized to investigate genetic diversity among 70 Korean barley varieties (Hordeum vulgare). Ninety nine microsatellite primer pairs were screened for 9 varieties. Twenty primer pairs showed highly polymorphic. The relationship between markers genotypes and 70 varieties was analyzed. A total of 124 polymorphic amplified fragments were obtained by using 20 microsatellite markers. Two to nine SSR alleles were detected for each locus with an average of 6.2 alleles per locus. Average polymorphism information content (PIC) was 0.734, ranging from 0.498 to 0.882. A total of 124 marker loci were used to calculate Jaccard's distance coefficients for cluster analysis using UPGMA. Clustering group was divided 2 groups corresponding to 2-rowed and 6-rowed barley varieties. The phenogram was discriminated all varieties by markers genotypes. These markers may be used wide range of practical application in variety identification and genetic purity assessment of barley.

• Nutrition Research and Practice
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• v.17 no.2
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• pp.307-315
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• 2023

BACKGROUND/OBJECTIVES: Previous studies have shown an association between breastfeeding and higher fruit and vegetable consumption and the level of dietary variety in children. However, few studies have reported this association on the feeding characteristics. Therefore, this study examined the association of the feeding characteristics with the consumption of fruit and vegetable and dietary variety in children. SUBJECTS/METHODS: This study recruited 802 participants from their parents with information on their feeding, and 24-h dietary recall. The associations of the feeding characteristics with fruit and vegetable consumption and dietary variety score (DVS) were analyzed using a multiple logistic regression model. RESULTS: Compared to the feeding type of exclusive breastfed children, exclusive formula-fed children had a significant association with a lower DVS (odds ratio [OR], 0.42, 95% confidence interval [CI], 0.23-0.77). Fruit and vegetable consumption was classified into 6 groups: non-salted vegetables (NSV), salted vegetables (SV), fruit (F), total vegetables (TV), non-salted vegetables + fruit (NSVF), and total vegetables + fruit (TVF). According to the mean level of fruit and vegetable consumption, compared to the duration of total breastfeeding for 6 month or less, a greater duration of breastfeeding for 12 mon had a significant association with a higher intake of NSVF and TVF (OR, 1.85, 95% CI, 1.20-2.85 and OR, 1.89, 95% CI, 1.22-2.92). On the other hand, the early introduction of formula feeding for 4 mon had a significant association with a lower intake of F and NSVF (OR, 0.59, 95% CI, 0.38-0.91 and OR, 0.63, 95% CI, 0.40-0.99). CONCLUSIONS: These results confirm that breastfeeding is associated with higher fruit and vegetable consumption and dietary variety, whereas formula feeding is associated with lower fruit and vegetable consumption and dietary variety. Therefore, the feeding characteristics in infants may affect fruit and vegetable consumption and dietary variety in children.

• Journal of Korea Trade
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• v.26 no.7
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• pp.1-18
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• 2022

Purpose - Recent international studies have largely focused on measuring the welfare gains from increased trade varieties. To adequately capture the variety gains, it is of importance to estimate the elasticity of substitution between varieties of trade goods because it is one of the key parameters to determine the magnitude of the variety gains. Using the import data of South Korea, this paper shows that the elasticities vary substantially across the estimators, which affects the magnitude of the gains from trade. Design/methodology - Empirical studies working on the gains from trade variety have heavily depended on the estimation methods for the elasticity of substitution between trade varieties, developed by Feenstra (1994) and refined by Broda and Weinstein (2006). We estimate and compare the estimated elasticities for 8,945 HS 10 goods of South Korea, obtained from the three estimation methods: Feenstra's weighted least square (F-WLS), Feenstra's feasible generalized least square (F-FGLS), and Broda and Weinstein's feasible generalized least square (BW-FGLS). Findings - Using the estimated elasticities from the F-FGLS, considered as a suitable estimator, A typical Korean consumer saved 228 dollars per year by the greater access to new import varieties. This leads to gains from imported variety of 2.06% of GDP. In 2017, a typical Korean consumer would gain by 611 dollars, compared with 2000. China is the country with the largest contribution (28.4%), followed by Japan and USA. About 50% of all the welfare gains come from the imports from the three main trade partners. The Southern Asian countries are more important to the South Korean welfare gain than the Western European countries. Originality/value - Existing studies have chosen one of the methods without any criterion for the choice and then estimated the elasticities of substitution between varieties of trade goods. This paper focuses on the estimation specifications and methods as the cause of the disparity in estimated elasticities and welfare gains from trade variety. According to the Ramsey RESET and White tests, the F-FGLS estimates are relatively better compared to the F-WLS and BW-FGLS estimates. As another contribution, this paper provides the first measure of the welfare gains from trade variety for South Korea, using the estimated elasticities of substitution between trade varieties.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.11a
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• pp.31.1-31.1
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• 2006

• East Asian mathematical journal
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• v.38 no.5
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• pp.611-616
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• 2022

This paper considers the Jacobian variety of a hyperelliptic curve over a finite field with mixed symmetric formal type. We present the Newton polygon of the characteristic polynomial of the Frobenius endomorphism of the Jacobian variety. It gives a useful tool for finding the local decomposition of the Jacobian variety into isotypic components.