• Journal of Ginseng Research
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• 제41권4호
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• pp.469-476
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• 2017

Background: Panax ginseng Meyer (Asian ginseng) has a large nuclear genome size of > 3.5 Gbp in haploid genome equivalent of 24 chromosomes. Tandem repeats (TRs) occupy significant portions of the genome in many plants and are often found in specific genomic loci, making them a valuable molecular cytogenetic tool in discriminating chromosomes. In an effort to understand the P. ginseng genome structure, we characterized an ultrahigh copy 167-bp TR (Pg167TR) and explored its chromosomal distribution as well as its utility for chromosome identification. Methods: Polymerase chain reaction amplicons of Pg167TR were labeled, along with 5S and 45S rDNA amplicons, using a direct nick-translation method. Direct fluorescence in situ hybridization (FISH) was used to analyze the chromosomal distribution of Pg167TR. Results: Recently, we reported a method of karyotyping the 24 chromosome pairs of P. ginseng using rDNA and DAPI (4',6-diamidino-2-phenylindole) bands. Here, a unique distribution of Pg167TR in all 24 P. ginseng chromosomes was observed, allowing easy identification of individual homologous chromosomes. Additionally, direct labeling of 5S and 45S rDNA probes allowed the identification of two additional 5S rDNA loci not previously reported, enabling the refinement of the P. ginseng karyotype. Conclusion: Identification of individual P. ginseng chromosomes was achieved using Pg167TR-FISH. Chromosome identification is important in understanding the P. ginseng genome structure, and our method will be useful for future integration of genetic linkage maps and genome scaffold anchoring. Additionally, it is a good tool for comparative studies with related species in efforts to understand the evolution of P. ginseng.

• 한국자원식물학회지
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• 제10권2호
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• pp.200-210
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• 1997

The understanding on the plant genome is accelerated with the fast advance of molecular biological techniques. The molecular dissecting of the plant genome has made possible the precise genotyping the plants, which can be utilized for molecular breeding program. As well, the molecular cloning of genes interested can facilitate the process of gene transfer between intra-and inter-generic taxa. Moreover, the manipulation of the agronomically important QTL genes, which can be rarely performed by the conventional genetic methods, is also possible by the utilization of molecular markers. In addition to these genetical applications, molecular markers are useful in the areas of plant taxonomy and management of germplasm by fingerprinting analysis. This paper describes the theoretical aspects marker technologies and practical applications of each marker technique.

• 한국식물학회:학술대회논문집
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• 한국식물학회 1987년도 식물생명공학 심포지움 논문집 Proceedings of Symposia on Plant Biotechnology
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• pp.9-18
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• 1987

The plant breeding, a discipline of agricultural sciences, has greatly contributed to huan welfare in relieving food crisis by development of higher yielding, stronger resistant and better quality varieties. However, many conventional plant breeders, especially ones working for major crops, are facing exhaustion of useful genetic variability, which greatly limit the potentional of developing better cultivars. Therefore, the convectional plant breeders have been eagerly looking for new renovational methods in creating genetic varibility. It has been expected that biotechnology would provide the technique to create totally new genetic variability through gene transfer, chromosome manipulation and/or cell fusion. It is strongly suggested that very close interdisciplinary approaches between convectionla plant breeders and biotechnoligists is essentional for opening new era in developing better varieties.

• 한국연초학회지
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• 제14권2호
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• pp.104-115
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• 1992

The present study was conducted to compare the relative efficiency of four different breeding methods in tobacco varietal development. A single Fl hybrid plant from cross of two flue-cured cultivars of Nicotiana tabacum L Bright Yellow 4(BY4) and NC95, was selfed. F2population above cross was screened for resistance against bacterial wilt caused by Pseudommonas solanacearum E.F.Smith under the naturally infested field conditions, and the 30 lines were developed from F2 individual plant by anther culture (ADH), maternal method utilizing Nicotiana afpicana (MDH), single- seed descent(SSD) and Bulk breeding method, respectively. All characters except content of total alkaloids of ADH and MDH which wore bred by haploid methods reduced more than that of lines bred by conventional methods(SSD & Bulk) : however, the yields were 8% lower than other lines. The total alkaloid content of ADH was higher than that of MDH, and yield was reduced about 4n even though the number of leaf was identical with the MDH. All other characters of ADH were also reduced significantly. In the lines bred by conventional methods, population developed by SSD showed significantly wider leaf width, shorter plant height, later days to flower, and lower in percent reducing sugar than those by Bulk. The populations derived from haploid method showed greater phenotypic variance and wider range of variation than conventionally developed ones. The results obtained indicate that selection will provide a significantly greater genetic gain for leaf number and leaf length in the ADU and MDH populations, and for plant height and days to flower in the SSD and Bulk populations.

• Journal of Forest and Environmental Science
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• 제24권1호
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• pp.15-25
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• 2008

Social and scientific changes, i.e., global warming, desertification, pollution, biodiversity, bioenergy, plant variety protection, biotechnology, timber demand, reforestation in North Korea, and etc., were reviewed for new strategy of forest tree breeding in Korea. Diversified breeding goals, globalization of breeding target species, multidisciplinary research approaches, manpower networking, establishment of new administrative and research units in KFS and KFRI were proposed. Principles suggested for new tree breeding strategy are: 1) multi-disciplinary approach in settlement of objectives, breeding methods, and etc., 2) expansion of target trees including foreign species, 3) fulfillment of both domestic and international demands for forest tree breeding, 4) establishment of breeding program well-grounded on genetic resources conservation, 5) acknowledgement of breeding products (i.e., variety, technique, gene, and etc.) as goods, and 6) provision of more research opportunities for young scientists. Lastly, ongoing tree breeding project in Indonesia and NTFP R&D Center at the College of Forest and Environmental Sciences, Kangwon National University were introduced as examples of desirable breeding projects based on target species diversification, multidisciplinary approach, and manpower networking.

• Journal of Ginseng Research
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• 제43권4호
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• pp.572-579
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• 2019

Background: Panax ginseng has been used in traditional medicine to strengthen the body and mental well-being of humans for thousands of years. Many elite ginseng cultivars have been developed, and ginseng cultivation has become well established during the last century. However, heat stress poses an important threat to the growth and sustainable production of ginseng. Efforts have been made to study the effects of high temperature on ginseng physiology, but knowledge of the molecular responses to heat stress is still limited. Methods: We sequenced the transcriptomes (RNA-Seq) of two ginseng cultivars, Chunpoong (CP) and Yunpoong (YP), which are sensitive and resistant to heat stress, respectively, after 1- and 3-week heat treatments. Differential gene expression and gene ontology enrichment along with profiled chlorophyll contents were performed. Results: CP is more sensitive to heat stress than YP and exhibited a lower chlorophyll content than YP. Moreover, heat stress reduced the chlorophyll content more rapidly in CP than in YP. A total of 329 heat-responsive genes were identified. Intriguingly, genes encoding chlorophyll a/b-binding proteins, WRKY transcription factors, and fatty acid desaturase were predominantly responsive during heat stress and appeared to regulate photosynthesis. In addition, a genome-wide scan of photosynthetic and sugar metabolic genes revealed reduced transcription levels for ribulose 1,5-bisphosphate carboxylase/oxygenase under heat stress, especially in CP, possibly attributable to elevated levels of soluble sugars. Conclusion: Our comprehensive genomic analysis reveals candidate loci/gene targets for breeding and functional studies related to developing high temperature-tolerant ginseng varieties.

• Journal of Forest and Environmental Science
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• 제26권2호
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• pp.95-102
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• 2010

Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant. Plant flowering and breeding characteristics are important for us to understand the reproduction of plant populations. The present study describes the floral biology and flowering phenology of J. curcas which is a prerequisite for hybridization program for genetic improvement through conventional breeding. The plant produces flowers in dichasial inflorescences. Normally, the flowers are unisexual, and male and female flowers are produced in the same inflorescence. Only a few male flowers are produced in an inflorescence, and fruits are produced only through pollination between different flowers from the same or different plants. This study includes a description of the inflorescence, flower anatomy of both male and female flowers, female : male ratio, pollen : ovule ratio, flowering phenology, pollen viability, stigma receptivity, comparison of selfing methods and a comparison of geitonogamy and xenogamy. This information may be useful in J. curcas breeding programmes.

• Journal of Plant Biotechnology
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• 제39권4호
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• pp.219-224
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• 2012

Alstroemeria plants are widely cultivated in many countries especially in Western Europe and North America and popularity has increased in recently due to its long-base life, large variety of colors and low energy requirement during cultivation period. So far, more than 60 species have been released on the commercial market in the world. To meet the demand of consumer and develop the elite Alstroemeria cultivars, conventional breeding including cross-hybridization and selection as well as mutation breeding were used. However, as other important ornamental plants such as lily, rose, carnation and orchids accepted the biotechnological methods, this newly-born approach should be applied and developed an optimized the genetic transformation system. Then, this biotechnological approach can be fused with the conventional breeding methods and thus can be contributed to the production of elite Alstroemeria plants containing agriculturally good genetic traits which are useful for the both farmers and consumers in the future. In this paper, we reviewed the botanical and genetical features of Alstroemeria plants and its biotechnological approaches in the last decades.

• Journal of Ginseng Research
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• 제38권2호
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• pp.130-135
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• 2014

Background: Panax ginseng, the most famous medicinal herb, has a highly duplicated genome structure. However, the genome duplication of P. ginseng has not been characterized at the sequence level. Multiple band patterns have been consistently observed during the development of DNA markers using unique sequences in P. ginseng. Methods: We compared the sequences of multiple bands derived from unique expressed sequence tagsimple sequence repeat (EST-SSR) markers to investigate the sequence level genome duplication. Results: Reamplification and sequencing of the individual bands revealed that, for each marker, two bands around the expected size were genuine amplicons derived from two paralogous loci. In each case, one of the two bands was polymorphic, showing different allelic forms among nine ginseng cultivars, whereas the other band was usually monomorphic. Sequences derived from the two loci showed a high similarity, including the same primer-binding site, but each locus could be distinguished based on SSR number variations and additional single nucleotide polymorphisms (SNPs) or InDels. A locus-specific marker designed from the SNP site between the paralogous loci produced a single band that also showed clear polymorphism among ginseng cultivars. Conclusion: Our data imply that the recent genome duplication has resulted in two highly similar paralogous regions in the ginseng genome. The two paralogous sequences could be differentiated by large SSR number variations and one or two additional SNPs or InDels in every 100 bp of genic region, which can serve as a reliable identifier for each locus.

• Molecules and Cells
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• 제37권1호
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• pp.36-42
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• 2014

The tomato (Solanum lycopersicum L.) is a model plant for genome research in Solanaceae, as well as for studying crop breeding. Genome-wide single nucleotide polymorphisms (SNPs) are a valuable resource in genetic research and breeding. However, to do discovery of genome-wide SNPs, most methods require expensive high-depth sequencing. Here, we describe a method for SNP calling using a modified version of SAMtools that improved its sensitivity. We analyzed 90 Gb of raw sequence data from next-generation sequencing of two resequencing and seven transcriptome data sets from several tomato accessions. Our study identified 4,812,432 non-redundant SNPs. Moreover, the workflow of SNP calling was improved by aligning the reference genome with its own raw data. Using this approach, 131,785 SNPs were discovered from transcriptome data of seven accessions. In addition, 4,680,647 SNPs were identified from the genome of S. pimpinellifolium, which are 60 times more than 71,637 of the PI212816 transcriptome. SNP distribution was compared between the whole genome and transcriptome of S. pimpinellifolium. Moreover, we surveyed the location of SNPs within genic and intergenic regions. Our results indicated that the sufficient genome-wide SNP markers and very sensitive SNP calling method allow for application of marker assisted breeding and genome-wide association studies.