• 한국육종학회지
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• 제42권2호
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• pp.144-150
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• 2010

The objective of this study was to map gene/QTL for photoblastism in a weedy rice (photoblastic rice: PBR) using DNA markers. Light-induced effect on germination of seeds was compared among three accessions (Oryza sativa L.), PBR, Milyang 23 and Ilpum. Results showed that PBR seeds started to show photoblastism during seed development, different from Ilpum and Milyang 23. Frequency distribution of germination in the F4 lines from crosses between Ilpum and PBR and, Milyang 23 and PBR revealed bimodal distributions suggesting that photoblastism was controlled by a few genes. Bulked segregant analysis using $F_4$ populations derived from the above two crosses was conducted to identify gene/QTL for photoblastism. Two QTL were identified on chromosomes 1 and 12 explaining 11.2 and 12.8% of the phenotypic variance, respectively. Two QTL were further mapped between two SSR markers, RM8260 and RM246 on chromosome 1, and between RM270 and 1103 on chromosome 12. It is noteworthy that two QTL for photoblastism were colocalized with the QTL for seed dormancy reported in the previous QTL studies. The clustering of two genes for photoblastism and dormancy possibly indicates that these regions constitute rice phytochrome gene clusters related to germination. Because PBR has a low degree of dormancy, a pleiotropic effect of a single gene controlling dormancy and photoblastism can be ruled out. The linked markers will provide the foundation for positional cloning of the gene.

• 원예과학기술지
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• 제16권1호
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• pp.21-24
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• 1998

참외와 멜론의 다양성 분석을 위하여 RAPD 분석 최적조건과 군집분석하였다. 참외와 멜론계통의 DNA 추출은 0.5% SDS 방법이 가장 순수하고 많은 DNA를 얻을 수 있었으며 DNA 증폭시 최적 반응조건은 총 volum $15{\mu}L$ 중 DNA 10ng, Primer 270nM, dNTP $200{\mu}M$, dynazyme 0.3unit. 10x buffer $1.5{\mu}l$이였으며 나머지는 3차 증류수로 보충된다. PCR기기의 최적 setting은 DNA denaturation $94^{\circ}C$ 30초, primer annealing $39^{\circ}C$ 30초, DNA extension $72^{\circ}C$ 30초이며 최적 증폭 횟수는 40 cycle 이었다. 사용된 12개의 primer 만들어진 총 123개의 band 중 신뢰도가 높은 25개(20%)의 polymorphic band를 선발하여 이용하였으며 평균 polymorphic band 수는 2.1개로 나타났고, 그룹내 polymorphic band 수가 그룹간보다 적어 그룹내의 유전적변이가 적음을 보여주었다. 군집분석 결과 크게 참외와 멜론그룹으로 나뉘었고 멜론그룹은 다시 net melon 과 no-net melon으로 나뉘었으며 이러한 결과는 기존의 표현형질에 의한 분류와 일치하였다. 재래종 참외와 멜론 그룹은 8개의 marker에 의해 구분되었고 net melon 그룹과 no-net melon 그룹은 4개의 marker에 의해 구분되었다.

• Molecules and Cells
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• 제24권1호
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• pp.83-94
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• 2007

During monocarpic senescence in higher plants, functional stay-green delays leaf yellowing, maintaining photosynthetic competence, whereas nonfunctional stay-green retains leaf greenness without sustaining photosynthetic activity. Thus, functional stay-green is considered a beneficial trait that can increase grain yield in cereal crops. A stay-green japonica rice 'SNU-SG1' had a good seed-setting rate and grain yield, indicating the presence of a functional stay-green genotype. SNU-SG1 was crossed with two regular cultivars to determine the inheritance mode and identify major QTLs conferring stay-green in SNU-SG1. For QTL analysis, linkage maps with 100 and 116 DNA marker loci were constructed using selective genotyping with $F_2$ and RIL (recombinant inbred line) populations, respectively. Molecular marker-based QTL analyses with both populations revealed that the functional stay-green phenotype of SNU-SG1 is regulated by several major QTLs accounting for a large portion of the genetic variation. Three main-effect QTLs located on chromosomes 7 and 9 were detected in both populations and a number of epistatic-effect QTLs were also found. The amount of variation explained by several digenic interactions was larger than that explained by main-effect QTLs. Two main-effect QTLs on chromosome 9 can be considered the target loci that most influence the functional stay-green in SNU-SG1. The functional stay-green QTLs may help develop low-input high-yielding rice cultivars by QTL-marker-assisted breeding with SNU-SG1.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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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.

• 생명과학회지
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• 제23권11호
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• pp.1317-1324
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• 2013

고분자 글루테닌 서버유닛(high molecular-weight glutenin subunit, HMW-GS)은 밀의 가공적성을 결정하는데 중요한 역할을 수행한다. 우리는 Agrobacterium 동시 형질전환법을 이용하여 한국 밀 품종인 '조경'으로부터 밀 HMW-GS을 암호화하는 Glu-1Bx7 유전자를 가지는 marker-free 형질전환 벼를 생산하였다. Glu-1Bx7 유전자의 종자 특이적 발현을 위하여 밀 Glu-1Bx7 유전자 자체 프로모터를 벡터 내에 삽입하였다. 동시 접종을 위해서 오직 Glu-1Bx7 유전자와 hygromycin phosphotransferase II (HPTII) 저항성 유전자만으로 구성된 두 종류의 발현 카셋트를 독립적으로 Agrobacterium EHA105에 도입하였고, Glu-1Bx7와 HPTII가 도입된 각각의 EHA105 Agrobacterium 을 3:1 비율로 혼합하여 벼 캘러스에 접종하였다. 216개의 HPTII 저항성 형질전환체 중에서 벼 게놈에 Glu-1Bx7과 HPTII가 모두 삽입된 24개의 형질전환 라인을 획득하였다. Glu-1Bx7와 HPTII가 벼 게놈에 도입된 것을 Southern blot을 통해서 다시 확인하였다. 형질전환 벼 $T_1$ 세대의 종자에서 밀 Glu-1Bx7 유전자가 전사와 번역되어 오직 Glu-1Bx7만을 가지는 marker-free 식물체를 $T_1$ 세대에서 성공적으로 선발할 수 있었다.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.38-38
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• 2015

Throughout the world, clubroot disease is one of the most damaging diseases affecting Brassica oleracea. In order to perform QTL analysis of CR (clubroot resistance) loci in B. oleracea, we constructed a map, and analyzed CR-QTLs using the mean phenotypes of F3 progenies from the cross of a resistant double-haploid cabbage line (Anju) with a susceptible double-haploid broccoli line (GC). We identified one major QTL, pb-Bo(Anju)1 in C2 from Anju and four minor QTLs; pb-Bo(GC)1 in O5 from GC, pb-Bo(Anju)2, -3, -4 in C2, C3, and C7 from Anju, respectively. Additionally, we found that the accumulation of Pb-Bo(Anju)1 allele and the minor CR-QTLs is essential for resistance against various six isolates. Our finding markers closely linked to the CR-QTLs will help marker-assisted selection for CR. At present, we are undergoing toward map-based cloning for Pb-Bo(Anju)1 gene. The preliminary experiment delimited Pb-Bo(Anju)1 locus, encompassing among 450kB.

• Journal of Plant Biotechnology
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• 제47권4호
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• pp.289-297
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• 2020

The genetic diversity of two subpopulations of Corynandra chelidonii, one of terrestrial and the other of aquatic environments, was measured with molecular markers, such as start codon targeted (SCoT), inter simple sequence repeats (ISSR), and random amplification of polymorphic DNA (RAPD). The traditional morphological traits such as habitat, habit, leaf morphology, the colour of the sepals and petals, number of stamens, and seed morphology formed the base for their realization as two varieties, C. chelidonii var. pallae and C. chelidonii var. chelidonii. The polymorphism between the two variants was 100% with the primers SCoT-2 and OPA-1 and 4, while maximum polymorphism was detected with ISSR-2, SCoT-3, and OPA-3. The study used, for the first time, more than one molecular marker to assess the genetic variation underscoring the morphological variation in Corynandra chelidonii (L.f.) Cochrane & Iltis. The study justifies the recognition of the two subpopulations of Corynandra chelidonii from aquatic and terrestrial environments as two distinct varieties, C. chelidonii var. pallae (Reddy & Raju) V.S.Raju and C. chelidonii var. chelidonii, respectively, based on the traditional taxonomic evidence.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.27-27
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• 2022

(-)-Epicatechin (EC), a primary form of flavan-3ol and a building block of proanthocyanidins, has health benefits as it is a potent antioxidant. So far, no quantitative trait loci (QTLs) associated with EC have yet been identified in soybean. In this study, QTLs for EC and hilum color were identified in recombinant inbred lines (RILs) derived from the varieties Jinpung and IT109098 using high-resolution single nucleotide polymorphism linkage mapping. This revealed two major QTLs for EC content, qEC06 and qEC08. qEC06 spanned the T Locus encoding flavonoid 3'-hydroxylase. qEC08, located near the I locus on Chr08, was also a major QTL for hilum color; however, allelic stacking of qEC08 and I revealed no relationship between I and EC content. RILs with IT 109098 alleles at both qEC06 and qEC08 had higher EC content than other lines. These results will enable the production of soybean varieties with high EC content via marker-assisted selection.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2020년도 춘계학술대회
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• pp.120-120
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• 2020

Based on the simple sequence repeat (SSR) marker, a Korean wheat core collection were established with 616 wheat accessions. Among them, the SNP genotyping for the entire genome was performed using DNA chip array to clarify the whole genome SNP profiles. Consequently, a total of 35,143 SNPs were found and we re-established a mini-core collection with 247 accessions. Population diversity and phylogenetic analysis revealed genetic diversity and relationships from the mini core set. In addition, genome-wide association study (GWAS) was performed on 19 phenotypic traits; ear type, awn length, culm length, ear length, awn color, seed coat color, culm color, ear color, loading, leaf length, leaf width, seeding stand, cold damage, weight, auricle, plant type, heading stage, maturation period, upright habit, and degree of flag leaf. The GWAS was performed using the fixed and random model circulating probability unification (FarmCPU), which identified 14 to 258 SNP loci related to 19 phenotypic traits. Our study indicates that this Korean wheat mini-core collection is a set of germplasm useful for basic and applied research with the aim of understanding and exploiting the genetic diversity of Korean wheat varieties.

• 식물병연구
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• 제30권1호
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• pp.50-59
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• 2024

Charcoal rot disease, caused by the fungus Macrophomina phaseolina, is one of the most important diseases of Sesame (Sesamum indicum) all over the world. However, the population biology of M. phaseolina is poorly understood. In this study, M. phaseolina isolates from five different regions of Iran (Khuzestan, Fars, Bushehr, Hormozgan, and Kohgiluyeh & Boyer-Ahmad provinces) (n=200) were analyzed for genetic variation using inter simple sequence repeats marker. In total, 152 unique haplotypes were identified among the 200 M. phaseolina isolates, and gene diversity (H=0.46-0.84) and genotypic diversity were high in each of the regions. The structure analysis clustered five Iranian populations into two distinct groups, the individuals from group 1 were assigned to the Bushehr population and the individuals from Khuzestan, Fars, Hormozgan and Kohgiluyeh & Boyer-Ahmad were aggregated and formed group 2. The results matched with genetic differentiation and gene flow among regions. Analyses of the distribution of gene diversity within and among five Iranian populations were 61% and 39%, respectively. Our results showed that infected seeds are thought to be the dominant mechanism responsible for the spreading of the pathogen in southern parts of Iran. In summary, it is essential to have local quarantine and prevent seed exchanges between geographical populations to restrict the dispersal of pathogen over long distances and provide certified seeds in Iran.