• Geomechanics and Engineering
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• v.27 no.6
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• pp.537-550
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• 2021

There are various technical problems need to be solved in the construction process of pre-setting an isolation wall into a double lane in the outburst prone mine. This study presents a methodology that pre-setting an isolation wall into a double lane without a coal pillar. This requires the excavation of two small section roadways to dig a wide section roadway, followed by construction of the separation wall. During this process the connecting lane is reserved. In order to ensure the stability of the separation wall, the required bearing capacity of the isolation wall is 4.66 MN/m and the deformation of the isolation wall is approximately 25 cm. To reduce the difficulty of implementing support the roadway is driven by 5 m/d. After the construction of the separation wall, the left side coal wall is brushed 1.5 m to make the width of the gas roadway reach 2.5 m and the roadway support utilizes anchor rod, ladder beam, anchor cable beam and net configuration. During construction, the concrete pump and removable self-propelled hydraulic wall mold are used to pump and pour the concrete of the isolation wall. In the process of mining, the stress distribution of coal body and isolation wall is detected and measured on site. The results demonstrate that the deformation of the surrounding rock of roadway and separation of roof in the roadway is small. The stress of the bolt and anchor cable is within equipment tolerance validating their selection. The roadway is well supported and the intended goal is achieved. The methodology can be used for reference for similar mine gas control.

• Animal Bioscience
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• v.36 no.7
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• pp.1003-1009
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• 2023

Objective: The objective was to compare (pedigree-based) best linear unbiased prediction (BLUP), genomic BLUP (GBLUP), and single-step GBLUP (ssGBLUP) methods for genomic evaluation of growth traits in a Mexican Braunvieh cattle population. Methods: Birth (BW), weaning (WW), and yearling weight (YW) data of a Mexican Braunvieh cattle population were analyzed with BLUP, GBLUP, and ssGBLUP methods. These methods are differentiated by the additive genetic relationship matrix included in the model and the animals under evaluation. The predictive ability of the model was evaluated using random partitions of the data in training and testing sets, consistently predicting about 20% of genotyped animals on all occasions. For each partition, the Pearson correlation coefficient between adjusted phenotypes for fixed effects and non-genetic random effects and the estimated breeding values (EBV) were computed. Results: The random contemporary group (CG) effect explained about 50%, 45%, and 35% of the phenotypic variance in BW, WW, and YW, respectively. For the three methods, the CG effect explained the highest proportion of the phenotypic variances (except for YW-GBLUP). The heritability estimate obtained with GBLUP was the lowest for BW, while the highest heritability was obtained with BLUP. For WW, the highest heritability estimate was obtained with BLUP, the estimates obtained with GBLUP and ssGBLUP were similar. For YW, the heritability estimates obtained with GBLUP and BLUP were similar, and the lowest heritability was obtained with ssGBLUP. Pearson correlation coefficients between adjusted phenotypes for non-genetic effects and EBVs were the highest for BLUP, followed by ssBLUP and GBLUP. Conclusion: The successful implementation of genetic evaluations that include genotyped and non-genotyped animals in our study indicate a promising method for use in genetic improvement programs of Braunvieh cattle. Our findings showed that simultaneous evaluation of genotyped and non-genotyped animals improved prediction accuracy for growth traits even with a limited number of genotyped animals.

• Animal Bioscience
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• v.35 no.9
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• pp.1289-1302
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• 2022

The next generation sequencing has significantly contributed to clarify the genome structure of many species of zootechnical interest. However, to date, some portions of the genome, especially those linked to a heterogametic nature such as the Y chromosome, are difficult to assemble and many gaps are still present. It is well known that the fluorescence in situ hybridization (FISH) is an excellent tool for identifying genes unequivocably mapped on chromosomes. Therefore, FISH can contribute to the localization of unplaced genome sequences, as well as to correct assembly errors generated by comparative bioinformatics. To this end, it is necessary to have starting points; therefore, in this study, we reviewed the physically mapped genes on the Y chromosome of cattle, buffalo, sheep, goats, pigs, horses and alpacas. A total of 208 loci were currently mapped by FISH. 89 were located in the male-specific region of the Y chromosome (MSY) and 119 were identified in the pseudoautosomal region (PAR). The loci reported in MSY and PAR were respectively: 18 and 25 in Bos taurus, 5 and 7 in Bubalus bubalis, 5 and 24 in Ovis aries, 5 and 19 in Capra hircus, 10 and 16 in Sus scrofa, 46 and 18 in Equus caballus. While in Vicugna pacos only 10 loci are reported in the PAR region. The correct knowledge and assembly of all genome sequences, including those of genes mapped on the Y chromosome, will help to elucidate their biological processes, as well as to discover and exploit potentially epistasis effects useful for selection breeding programs.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.252-252
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• 2022

Genotype-by-environment interaction (GEI) refers to the comparative response of genotypes to different environments conditions. Thus, understanding GEI is a fundamental component for selecting superior genotypes for breeding programs. The significance of utilizing early maturing cultivars not only provides flexibility in planting dates, but also serves as an effective strategy to reduce methane emission from the paddy fields. In this study, we conducted multi-environment trials (METs) to evaluate yield-related traits such as culm length, panicle length, panicle number, spikelet per plant, and thousand grain weight. A total of eighty-one Korean commercial rice cultivars categorized as early maturing cultivars, were cultivated in three regions, two planting seasons for two years. The genotype main effect plus genotype-by-environment interaction (GGE) biplot analysis of yield-related traits and grain yield explained 70.02-91.24% of genotype plus GEI variation, and exhibited various patterns of mega-environment delineation, discriminating ability, representativeness, and genotype rankings across the planting seasons and environments. Moreover, simultaneous selection using weighted average of absolute scores from the singular value decomposition (WAASB) and multi-trait stability index (MTSI) revealed six highly recommended genotypes with high stability and crop productivity. The winning genotypes under specific environment can be utilized as useful genetic materials to develop regional specialty cultivars, and recommended genotypes can be used as elite climate-resilient parents to improve yield-potential and reduce methane emission as part to accomplish carbon-neutrality.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2021.04a
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• pp.9-9
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• 2021

Mutation breeding is useful for improving agronomic characteristics of various crops. In this study, we constructed soybean Mutant Diversity Pool (MDP) from 1,695 gamma-irradiated mutants through two selection phases over M1 to M12 generations; we selected 523 mutant lines exhibiting at least 30% superior agricultural characteristics, and, second, we eliminated redundant morphological phenotypes in the M12 generation. Finally, we constructed 208 MDP lines and investigated 11 agronomic traits. We then assessed the genetic diversity and inter-relationships of these MDP lines using target region amplification polymorphism (TRAP) markers. Among the different TRAP primer combinations, polymorphism levels and PIC values averaged 59.71% and 0.15, respectively. Dendrogram and population structure analyses divided the MDP lines into four major groups. According to an analysis of AMOVA, the percentage of inter-population variation among mutants was 11.320 (20.6%), whereas mutant inter-population variation ranged from 0.231 (0.4%) to 14.324 (26.1%). Overall, the genetic similarity of each cultivar and its mutants were higher than within other mutant populations. In an analysis of the genome-wide association study (GWAS) using based on the genotyping-by-sequencing (GBS), we detected 66 SNPs located on 13 different chromosomes were found to be highly associated with four agronomic traits: days of flowering (33 SNPs), flower color (16 SNPs), node number (6 SNPs), and seed coat color (11 SNPs). These results are consistent with those previously reported for other genetic resource populations, including natural accessions and recombinant inbred line. Our observations suggest that genomic changes in mutant individuals induced by gamma rays occurred at the same loci as those of natural soybean population. This study has demonstrated that the integration of GBS and GWAS can serve as a powerful complementary approach to gamma-ray mutation for the dissection of complex traits in soybean.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.101-105
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• 2012

'Secret Pink' was released by National Institute of Horticultural & Herbal Science in 2008. The cross was made between '03B1-23' and 'Sei-Monaco in 2005'. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2006 to 2008, 'Secret Pink' was selected finality. The natural flowering time of 'Secret Pink' was the middle of October, and it is possible to flower all year round by shade and light culture. It has single type flowers with pink petals. The growth of plant was very vigorous and response time was 6.5 weeks. The diameter of flower was 6.7 cm. Number of flowers per stem and petals per flower were 14.5 and 25, respectively. Days to flowering under the short day treatment was about 50 and its vase life was 25.5 days in autumn season.

• Horticultural Science & Technology
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• v.33 no.6
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• pp.941-946
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• 2015

A new Doritaenopsis cultivar 'Hwasu 5205' was bred by Kyungpook National University, Korea, which produces young plants through tissue culture techniques. The new cultivar 'Hwasu 5205', showing the phenotype of vivid red and large flower type characteristics, was derived from crossing between Phalaenopsis Happy Valentine and Doritaenopsis Happy Rose. An elite individual, number '02-05-205' later named as 'Hwasu 5205', was selected among about 300 individual progenies after more than 2 years of intensive selection covering vegetative and flowering distinctiveness. In year 2004-2005, 1st and 2nd characteristic analyses were carried out through performance and uniformity tests. 'Hwasu 5205' produces vivid red (RHS #PN78B) flowers of i ncurved type with large size, of 9.2 and 12.0 cm in flower height and width, respectively. Leaves of 'Hwasu 5205' grow horizontally and are about 24.3cm in length and 8.5cm in width, respectively. This cultivar possesses no genetic variation. It can be propagated rapidly in vitro and is easy to grow due to its vigorous growth habit. 'Hwasu 5205' was registered (Reg. #: 2915) to Korea Seed & Variety Service (KSVS) on 1st December, 2009 and the PBR(plant breeder's right)is currently controlled by Sangmiwon Orchid Company, Korea.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.303-310
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• 2015

The study was conducted to analyze the genetic parameters of somatic cell score (SCS) of Holstein cows, which is an important indicator to udder health. Test-day records of somatic cell counts (SCC) of 305-day lactation design from first to fifth lactations were collected on Holsteins in Korea during 2000 to 2012. Records of animals within 18 to 42 months, 30 to 54 months, 42 to 66 months, 54 to 78 months, and 66 to 90 months of age at the first, second, third, fourth and fifth parities were analyzed, respectively. Somatic cell scores were calculated, and adjusted for lactation production stages by Wilmink's function. Lactation averages of SCS ($LSCS_1$ through $LSCS_5$) were derived by further adjustments of each test-day SCS for five age groups in particular lactations. Two datasets were prepared through restrictions on number of sires/herd and dams/herd, progenies/sire, and number of parities/cow to reduce data size and attain better relationships among animals. All LSCS traits were treated as individual trait and, analyzed through multiple-trait sire models and single trait animal models via VCE 6.0 software package. Herd-year was fitted as a random effect. Age at calving was regressed as a fixed covariate. The mean LSCS of five lactations were between 3.507 and 4.322 that corresponded to a SCC range between 71,000 and 125,000 cells/mL; with coefficient of variation from 28.2% to 29.9%. Heritability estimates from sire models were within the range of 0.10 to 0.16 for all LSCS. Heritability was the highest at lactation 2 from both datasets (0.14/0.16) and lowest at lactation 5 (0.11/0.10) using sire model. Heritabilities from single trait animal model analyses were slightly higher than sire models. Genetic correlations between LSCS traits were strong (0.62 to 0.99). Very strong associations (0.96 to 0.99) were present between successive records of later lactations. Phenotypic correlations were relatively weaker (<0.55). All correlations became weaker at distant lactations. The estimated breeding values (EBVs) of LSCS traits were somewhat similar over the years for a particular lactation, but increased with lactation number increment. The lowest EBV in first lactation indicated that selection for SCS (mastitis resistance) might be better with later lactation records. It is expected that results obtained from these multi-trait lactation model analyses, being the first large scale SCS data analysis in Korea, would create a good starting step for application of advanced statistical tools for future genomic studies focusing on selection for mastitis resistance in Holsteins of Korea.

• Horticultural Science & Technology
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• v.31 no.3
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• pp.388-392
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• 2013

A spray chrysanthemum cultivar 'Green Candy' was released by National Institute of Horticultural & Herbal Science, Rural Development Administration, in 2009. The cross between 'Yoko Ono', a spray chrysanthemum cultivar with light yellowish-green double type, and 'Green Bird', a spray chrysanthemum cultivar with vigorous and green double type, was made in Suwon in 2006. After the evaluation of the characteristics under shade culture in summer and retarding culture in spring and consecutive selection from 2007 to 2009, 'Green Candy' was selected finality. The natural flowering time of 'Green Candy' is October 28th, and it is possible to flower all year-round by shade and light culture. It has double flower type with green petals. The growth of plant is very vigorous and the color of the petals is stable when the variety is cultivated under high temperature conditions in summer season. The diameter of flower is 4.1 cm. The numbers of flower per stem and petals per flower are 12 and 217, respectively. The days for flowering under the short day treatment are about 58 and its vase life is 18.1 days in autumn season. 'Green Candy' was applied as No. 2010-212 on March 5, 2010 for variety protection and the plant variety protection rights have been registered as No. 3633 on August 2, 2011 at the Korea Seed and Variety Service.

• Horticultural Science & Technology
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• v.30 no.2
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• pp.224-228
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• 2012

A new $Saxifraga$ $fortunei$ cultivar 'Crystal' was bred by crossing 'Dotaerang' with light pink and light Green (RP 58D) colored petals and 'Rocksun' with light pink and light green white (RP62A + GW157A) colored petals. The selection and flower characterization were conducted from 2004 to 2007 in a greenhouse of the National Institute of Highland Agriculture. The flowering of 'Crystal' occurred from September 21 for 31 days. The number of flowers per plant was 279.0 with many flowering habit. The flower coloration was mixed light pink and green white (RP62D + GW157B) at the opening. The number of petals were 7.0, with a width of 2.1 cm and length of 1.8 cm. The plant height was 15.3 cm and number of leaves was 133.7. 'Crystal' cultivar can be used for pot flower. Fifty percent shading is a good cultural practice against direct sunlight and soft rot disease would occurs usually by over-irrigation. 'Crystal' cultivar was registered as a new variety with No. 3466 at Korea Seed and Variety Service in April of 2011 year.