• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.1
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• pp.39-46
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• 1980

A male sterile facilitated recurrent selection population was developed by the barley breeding team of Yeongnam Crop Experiment Station. To breed this population, three composite cross populations and a composite population of breeding lines in our country were used as the materials. This population was developed in order to breed early maturing, wet-soil tolerant and high yielding barley varieties, adapted for double cropping with rice in southern part of Korea. The population was named by RSPYB#l which means Recurrent Selection Population No.1. of Yeongnam Barley.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.235-235
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• 2022

Genome selection is a promising tool for plant and animal breeding, which uses genome-wide molecular marker data to capture large and small effect quantitative trait loci and predict the genetic value of selection candidates. Genomic selection has been shown previously to have higher prediction accuracies than conventional marker-assisted selection (MAS) for quantitative traits. In this study, the prediction accuracy of 10 agricultural traits in the wheat core group with 567 points was compared. We used a cross-validation approach to train and validate prediction accuracy to evaluate the effects of training population size and training model.As for the prediction accuracy according to the model, the prediction accuracy of 0.4 or more was evaluated except for the SVN model among the 6 models (GBLUP, LASSO, BayseA, RKHS, SVN, RF) used in most all traits. For traits such as days to heading and days to maturity, the prediction accuracy was very high, over 0.8. As for the prediction accuracy according to the training group, the prediction accuracy increased as the number of training groups increased in all traits. It was confirmed that the prediction accuracy was different in the training population according to the genetic composition regardless of the number. All training models were verified through 5-fold cross-validation. To verify the prediction ability of the training population of the wheat core collection, we compared the actual phenotype and genomic estimated breeding value using 35 breeding population. In fact, out of 10 individuals with the fastest days to heading, 5 individuals were selected through genomic selection, and 6 individuals were selected through genomic selection out of the 10 individuals with the slowest days to heading. Therefore, we confirmed the possibility of selecting individuals according to traits with only the genotype for a shorter period of time through genomic selection.

• Korean Journal of Breeding Science
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• v.42 no.4
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• pp.374-380
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• 2010

In order to select excellent cross parents in strawberry breeding, 11 varieties were self-pollinated and tested their progenies. Among the 11 varieties, 'Akihime', 'Maehyang' and 'Seolhyang' showed superior in plant vigor, disease resistance and yield. Combining ability was tested using 15 progenies obtained from crosses between 3 selected varieties as seed parents and 5 varieties as pollen parents. Plant vigor was the strongest when 'Akihime' was used as a seed parent while ripening time tended to the fastest when 'Seolhyang' as a seed parent. Average fruit weight of the crosses 'Seolhyang' ${\times}$ 'Tochiotome', 'Seolhyang' ${\times}$ 'Geumhyang', 'Seolhyang' ${\times}$ 'Wongyo 3111' and 'Akihime' ${\times}$ 'Wongyo 3111' were above 18 g for marketable fruits. Fruit hardness was superior at crosses of 'Maehyang' as a seed parents to other crosses combinations, especially 'Maehyang' ${\times}$ 'Tochiotome'. Soluble solid contents (SSC) was not significantly different among cross combinations. The best cross combination for marketable yield was 'Akihime' ${\times}$ 'Wongyo 3111', followed by 'Seolhyang' ${\times}$ 'Geumhyang', 'Maehyang' ${\times}$ 'Geumhyang', 'Akihime' ${\times}$ 'Tochiotome', in order.

• Horticultural Science & Technology
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• v.19 no.3
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• pp.348-351
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• 2001

'Saenara' released by National Horticultural Research Institute in 1997 is a mid-season apple cultivar with attractive red skin, high quality and high productivity. This cultivar originated from the cross between 'Spur EarliBlaze' and 'Spur Golden Delicious' at Suwon in 1981. It was first selected in 1992 and named 'Wonkyo Ga-08'. The regional adaptability test was carried out for 5 years from 1993 to 1997 at 7 different sites. 'Saenara' is medium in tree vigor and has a spreading tree form. It bears abundant flower buds on many spurs. It blossoms a day earlier than 'Spur Golden Delicious', 3 days later than 'Spur EarliBlaze'. Harvesting time of 'Saenara' is September 10, 140 days after full bloom at Suwon. Fruit shape is conical and skin color is bright red. Fruit weighs about 300 g and has $14.6^{\circ}Brix$ soluble solids content. It is susceptible to alternaria leaf spot (Alternaria mali Roberts).

• Molecules and Cells
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• v.37 no.2
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• pp.149-160
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• 2014

Plant breeders have focused on improving plant architecture as an effective means to increase crop yield. Here, we identify the main-effect quantitative trait loci (QTLs) for plant shape-related traits in rice (Oryza sativa) and find candidate genes by applying whole genome re-sequencing of two parental cultivars using next-generation sequencing. To identify QTLs influencing plant shape, we analyzed six traits: plant height, tiller number, panicle diameter, panicle length, flag leaf length, and flag leaf width. We performed QTL analysis with 178 $F_7$ recombinant inbred lines (RILs) from a cross of japonica rice line 'SNU-SG1' and indica rice line 'Milyang23'. Using 131 molecular markers, including 28 insertion/deletion markers, we identified 11 main- and 16 minor-effect QTLs for the six traits with a threshold LOD value > 2.8. Our sequence analysis identified fifty-four candidate genes for the main-effect QTLs. By further comparison of coding sequences and meta-expression profiles between japonica and indica rice varieties, we finally chose 15 strong candidate genes for the 11 main-effect QTLs. Our study shows that the whole-genome sequence data substantially enhanced the efficiency of polymorphic marker development for QTL fine-mapping and the identification of possible candidate genes. This yields useful genetic resources for breeding high-yielding rice cultivars with improved plant architecture.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.931-937
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• 2006

The full-length cDNA of the porcine SMPX gene was obtained by the rapid amplification of cDNA ends (RACE). The nucleotide sequences and the predicted protein sequences share high sequence identity with both human and mouse. The promoter of SMPX was sequenced and then analyzed to find the promoter binding sites. The reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that SMPX has a high level of expression in heart and skeletal muscle, a very low expression in lung and spleen and no expression in liver, kidney, fat and brain. Moreover, SMPX has a differential expression level in skeletal muscle, the expression in 65-day embryos being higher than other stages. The porcine SMPX was mapped to SSCXp24 by using a somatic cell hybrid panel (SCHP) and was found closely linked to SW1903 using the radiation hybrid panel IMpRH. An A/G single nucleotide polymorphism (PCR-RFLP) in the 3'-untranslated region (3'-UTR) was detected in eight breeds. The analysis of allele frequency distribution showed that introduced pig breeds (Duroc and Large White) have a higher frequency of allele A while in the Chinese indigenous pig breeds (Qingping pig, Lantang pig, YushanBlack pig, Large Black-White pig, Small Meishan) have a higher frequencies of allele G. The association analysis using an experimental population (188 pigs), which included two cross-bred groups and three pure-blood groups, suggested that the SNP genotype was associated with intramuscular fat content.

• Journal of Crop Science and Biotechnology
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• v.11 no.4
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• pp.257-262
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• 2008

Genetic diversity of cultivated wheat is narrowing down and is increasingly becoming non-complacent in tackling new pathogenic races and adverse environmental situations. Wild relatives of wheat are rich repositories of beneficial genes that are capable of defying adverse situations. However, these wild species are not readily crossable with cultivated ones. The present study attempted to cross three wild wheat species as females with three cultivated species of varying ploidy to understand the intricate behaviour of hybrids in relation to cytology, morphology, and molecular recombination. Post-fertilization barriers caused hybrid recovery in wild species in contrast to cultivated species. Triticum monococcum did not produce hybrids in any of the crosses. Various degrees of chromosome anomalies and hybrid sterility were seen with hybrids of T. timopheevi and T. sphaerococcum. Cytoplasmic factors were suspected to add more to the abnormality. G genome from T. timopheevi could enhance more pairing between Band D of cultivated species. Precocity of certain chromosomes in laggard formation was evident, pointing towards evolutionary self balance of the genomes which prevented homeologous pairing. They are eliminated in hybrids. Molecular diversity clearly corroborated with genetic proximity of the species, which distinguished themselves by maintaining the genome homeology.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.20-20
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• 2022

A traditional wheat breeding program needs more than 12-13 years to develop a new cultivar. In recent years, 'Speed breeding (SB)' system, which uses extremely extended photoperiod (22 h), enabled up to 4-6 generations of spring wheat per year. However, since almost 70% of wheat cultivars are winter type, and over 95% of total cultivation area is for winter wheat in Korea, optimized vernalization treatment was essential for improving the SB system. Several vernalization temperatures and durations were tested with various genotypes, and the 4 weeks of 8-10 ℃ vernalization treatment was the most effective to develop 4 generations per year, for both spring and winter type wheat cultivars. This 'Speed vernalization (SV)' system followed by SB, allowed developing a new F₆ recombinant inbred lines (RILs) within 2 years. Among the 184 RILs, which derived from a cross between Jokoyung and Joongmo2008, two outstanding lines were selected for yield trial test, and then named Milyang52 and Milyang53. Compared to the traditional wheat breeding program, over 60% of the time was saved to develop these two lines. Marker-assisted selection and backcross were also combined with the SV system. YW3215-2B-1 (Jokoyung*3/Gamet), which has similar agronomic traits with Jokyoung and the same Glu-B1 allele with Garnet, was developed within 2.5 years. Thus, the SV system combined with molecular breeding technology would help breeders to make a new cultivar with less time and high efficiency.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.269-269
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• 2022

Pre-harvest sprouting (PHS) on rice panicles is getting problematic in recent several years in Korea due to climate changes such as high temperature and more frequent typhoons during harvesting season. PHS negatively affects grain quality severely and also yield. Genetic improvement of Korean varieties (Oryza sativa ssp. japonica) through a marker assisted-backcross breeding (MAB) with the known PHS resistant genes must be one of ideal solutions. However, the final breeding products of MAB occasionally exhibit unwanted traits, especially the cross between genetically distant parents. This might be caused by linkage drag and/or presence of the gene-unlinked donor introgressions, resulting that the final products could not be released to the farmers. The major PHS resistance gene, Sdr4 (Seed dormancy 4) originated from an indica cultivar, Kasalath was selected as a donor gene. In order to avoid unexpected phenotypes in the breeding products, we performed a precision marker-based breeding (PMBB) consisting of foreground, recombinant, and background selections (FS, RS, and BS) which aim to develop 'single small introgression lines' (~100 kb introgression). Korean varieties (Ilpum and Gopum) were crossed with Kasalath. We developed Sdr4-allele specific markers for FS and a set of polymorphic flanking markers near the Sdr4 (-350kb and +420kb) for RS. To minimize linkage drag, the small introgression (< 125kb) containing Sdr4 was selected in Ilpum background (BC₂F₄) through 1^st RS with ~1,200 F₂ or BC₁F₂ plants (one side trimmed) and then 2^nd RS with ~1,000 progenies from the 1^st RS selected plants (another side trimmed). After RS, the selected lines were genotyped by using Infinium 7K SNP chip to detect other donor introgressions and the lines were backcrossed. Currently BS is on-going from the backcross-derived progenies with BS markers to remove residual introgressions. During the PMBB process, genetic effect of Sdr-4-Kasalath allele was confirmed in Ilpum and Gopum backgrounds by PHS phenotyping using the segregating BC₂F₃ or BC₁F₄ materials. The Sdr4 PMBB lines in Ilpum background (< 125kb introgression) will be valuable genetic resources to improve PHS resistance in modem popular temperate japonica varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.2
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• pp.49-57
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• 1980

A $F_1$ hybrid out of 143 crosses of rape (Brassica napus) using cytoplasmic-genetic male sterility yielded 5.18 tons per hectare. European and native varieties used, were found out to have 78% and 58% of genes restoring fertility, respectively. The $F_1$ hybrids of three way cross using non-isogenic maintainer showed higher heteroses than those of double cross. To produce F 1 hybrids of three way cross, three stages of crossing operations are needed and seeds produced from about 60 hectares can be covered to 60, 000 hectares.