• Korean Journal of Breeding Science
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• v.40 no.2
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• pp.101-105
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• 2008

The germplasm of 246 rice cultivars was analysed for iron and zinc contents using a Inductively Coupled Argon Plasma (ICP) at International Rice Research Institute (IRRI) Philippines. Iron contents ranged from 2.0 to 12.0, and zinc ranged from 10.0 to 33.0 (mg/kg), showing with the mean values of 4.3 and 22.8 (mg/kg), respectively. In genotypes tested, there was approximately a two-fold difference in iron and zinc concentrations, suggesting a genetic potential to increase these micronutrients in rice grain. A highly significant positive correlation ($r^2=0.503$) was found between iron and zinc contents. Iron contents decreased drastically as polishing time increased, whereas zinc decreased only slightly. In the interaction between genotype and environment on iron contents, genotype (G), environment (E), and the G ${\times}$ E interactions accounted for 69%, 5% and 26% of the sums of squares, respectively. Indicating that genotype is would be the most significant factor for the to improve iron contents of rice in rice breeding, suggesting that therefore identifying genotypes with relatively stable performance across various environments is important as staple food crops.

• Plant Breeding and Biotechnology
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• v.5 no.3
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• pp.213-220
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• 2017

Production of spring wheat, the major crop in Mongolia, accounts for 98% of the cultivated area. Understanding genetic variability in existing gene bank accessions is critical for collection, conservation and use of wheat germplasms. To determine genetic diversity and population structure among a representative collection of Mongolian local wheat cultivars and lines, 200 wheat accessions were analyzed with 15 SSR markers distributed throughout the wheat genome. A total of 85 alleles were detected, with three to five alleles per locus and a mean genetic richness of 5.66. Average genetic diversity index was 0.69, with values ranging from 0.37-0.80. The 200 Mongolian wheat accessions were mainly divided into two subgroups based on structure and phylogenetic analyses, and some phenotypes were divergent by the subgroups. Results from this study will provide valuable information for conservation and sustainable use of Mongolian wheat genetic resources.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.68-68
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• 2022

The pepper mild mottle virus (PMMoV), belonging to the tobamovirus genus, is currently one of the most destructive pathogens in pepper production. Tobamoviruses have been classified in terms of increased pathogenicity as pathotypes P₀, P₁, P_1,2, P_1,2,3 and P_1,2,3,4, based on their ability to infect systemically Capsicum L⁰ , L¹ , L² , L³ and L⁴ resistant plants, respectively. Two hundred eighty pepper germplasms and 5 reference accessions known as resistant L alleles, were analyzed to select the resistance cultivars against PMMoV- P_1,2,3 (CV130614-2) using bioassay and genetic markers. The susceptible accessions showed systemic symptom when inoculated with PMMoV- P_1,2,3. However, accessions including IT223737, were resistant as they developed necrotic local lesions only on inoculated leaves, whereas no symptoms were observed on the upper leaves. Moreover, RT-PCR results for detecting the presence of virus were also negative. Thus, those accessions will be used as a novel source to facilitate introduction the resistant gene into commercial cultivars of pepper.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.35-35
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• 2022

Pears (Pyrus spp.) have been grown worldwide as a kind of important economical fruits. Over 1,500 accessions collected from countries have been preserved in National Institute of Horticultural and Herbal Science, Rural Development Administration in Korea. However, redundancies and misidentification are happening in the germplasm preservation due to same cultivars which have different names in various localities (synonyms) and different cultivars which have same names (homonyms). That can lower germplasm management efficiency. The object of this study is to identify synonyms and homonyms in pear germplasms by analyzing genetic variation with four microsatellite markers: CH03d12, CH03g07, CH02b10, and EMPc117. PCR amplification with above 4 microsatellite markers was done for the 31 pear accessions, and the products were analyzed by agarose gel electrophoresis. As a result, 7 synonyms and 9 homonyms were identified among 31 pear accessions. We'll compare these genotypes with phenotypes of each pear accessions, and reduces the redundancy and misidentification in pear germplasm collection for the reliable management.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.79-84
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• 2012

An efficient protocol for cryopreservation of madder hairy root cultures has been developed using droplet-vitrification. In previous study, combining loading solution C4 (35% PVS3) and vitrification solution B5 (80% PVS3) was the most effective method. In this study, we tried three types of vitrification solution, B5, A3 (90% PVS2, on ice), and A5 (70% PVS2, on ice). Combining loading solution C4 and vitrification solution A5 (on ice) showed the best regeneration rate in this study. Histological changes of the cells within the hairy root of madder were also observed in different steps. The cells from the hairy roots of the control treatment were full and intact with different size of vacuoles and obvious cell nucleus having a dark nucleolus. After the stage of preparing for cryopreservation (after preculturing, loading, followed by dehydration solution A5 or B5), intercellular spaces had become distinct, and within cells, the cytoplasms had become denser and week plasmolyses had appeared. The cell plasmolyses were much more apparent and we measured the degree of plasmolysis by calculating, the area of cell/the area of cytoplasm. The value of plasmolysis degree was the highest in the combination of preculture, loading solution C4, and dehydration solution A5, 1.97. Because the highest regeneration rates appeared in the treatment of A5 for 20 min, we could assume that the optimal degree of plasmolysis for cryopreservation might be around 1.97. The changes in cell structure during cryopreservation might be a useful basis for the development of a proper long-term preservation method for madder germplasms.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.spc1
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• pp.94-109
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• 1996

Antioxidants of sesame have been reported to cure and prevent various diseases by means of diverse physiological activities, prevention of acidification in organisms, prevention of acidification and decay of lipids, cholesterol depression, preventive effects on chemical breast cancer, skin beauty and senescence inhibition, and so on. Recognizing their significance to health and disease prevention, researchers in Japan and America have given so much importance to study antioxidants in the last decade. In addition, they are actively pursuing studies on production, processing for food use and development of new varieties that have high antioxidant content. Recently, researchers in Korea have shown the same interest and have conducted similar studies, however, the importance of the following basic issues must be recognized to guide in future activites : First, improvement of sesame quality must be done to raise the contents of not only the fat and fatty acid but also sesamin, sesamolin and sesaminol glucoside. For the use of these components it is necessary to study the gentic pattern and individual selections developed from minimum sample size and fast lipid analysis techniques. Second, sesaminol of sesame has a remarkable function in preventing acidification and so sesame can be utilized as a food that prevents or delays aging caused by automatic acidification of fat. Therefore, for maximum medicinal benefit from sesame oil there is a need to develop food materials having new medicinal functions. Third, the sesamin and sesamolin content of sesame germplasms collected in Korea showed lower ranges of $0.04\~0.68$ percent and $0.08\~0.68$ percent respectively, while Japanese germ-plasm showed 1.9 percent maximum content of seasmin. Thus, germplasm collection and analysis of worldwide genetic resources are urgently needed.

• Korean Journal of Medicinal Crop Science
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• v.13 no.5
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• pp.249-253
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• 2005

This study was carried out to develop convenient and reproducible methods for identifying the genetic relationship among germplasms of Panax species based on molecular genetics. Using random amplified polymorphic DNA (RAPD) and inter simple sequence repeat (ISSR) analyses, genetic polymorphism of the Panax species was investigated with following cultivars and accessions, such as Chunpoong, Yunpoong, Kopoong, Sunpoong, and Kumpoong in domestic cultivars, Hwangsuk, Jakyung and Suckju in domestic accessions, and Panax quinquefolius L. and Panax japonicus C.A. Meyer in foreign introduced accessions, respectively. Specific DNA fragments ranging from 200 to 3,000 base pairs in size could be obtained with various ISSR and RAPD primers under the optimized PCR conditions. The dissimilarity coefficients among the genetic polymorphisms of ginseng cultivars and accessions were calculated from 0.26 to 0.90 in RAPD and from 0.12 to 0.89 in ISSR analysis, respectively. Eleven plant samples were grouped siblings together with cultivars and parents based on cluster analysis of genetic distance depending on genetic property such as origin of the species. In results, both RAPD and ISSR analyses were useful for identifying the genetic relationship among cultivars and accessions of Panax species at DNA level.

• The Plant Pathology Journal
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• v.27 no.4
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• pp.324-332
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• 2011

Soil-borne barley yellow mosaic disease caused by Barley yellow mosaic virus (BaYMV) or Barley mild mosaic virus (BaMMV) gives a serious threat to the winter barley cultivated in the southern regions in Korea. It is important to develop resistant varieties for stable and high-yield production. The objectives of this study were to evaluate 22 genotypes of exotic barley germplasms carrying the resistance genes rym1 through rym12, with the exception of rym10, and to determine the genes that confer resistance to BaYMV or BaMMV in Korea. Using the traditional visual scoring of symptoms at 4 locations over 3 years, average disease rate values differed (P < 0.001) among the genotypes. ELISA test revealed the presence of both BaYMV and BaMMV in all of the field sites but Jinju and significantly different rates of infection among genotypes and years. Barley genotypes differed in how virus quantities and pathogen-induced symptoms were correlated, especially in response to BaYMV. Disease incidence was affected by the climatic conditions present during the early growing stage before overwintering. A Chinese landrace, 'Mokusekko 3', carrying rym1 and rym5 was comparatively resistant at all locations studied. The barley genotypes carrying either rym6 or rym9 were susceptible to the viral strains. The genotypes carrying rym5 were resistant in Jinju and Milyang but susceptible in Iksan and Naju. The resistance genes rym2 and rym3 were effective in local strains and would be potent contributors to disease resistance.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.70-79
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• 2010

Rice blast is one of the serious devastating diseases. This study was carried out to determine the genetic diversities of blast resistance (R) genes form 86 accessions of aromatic rice with eight SNP markers, z4792, zt4792, z60510, zt6057, k6415, k6411, k39575 and t256, which showed the close-set linkage to 6 major genes, Piz, Piz-t, Pik, Pik-m, Pik-p, and Pit. Four accessions of indica type, Mayataung, Yekywin Yinkya Hmwe, Basmati9-93, and Basmati5854, showed the positive amplicons of six major genes. Among 86 accessions, 83 accessions were detected both or one of Piz and Piz-t genes. Seventy three accessions contained the Piz gene with z4792 marker. In addition, 30 and 71 accessions possessed Piz-t gene with zt4792 and zt6057 markers, respectively. Ten accessions showed the positive bands for the Piz-t gene with both zt4792 and zt6057 markers. Only one accession, Khau Nua Keo, was not amplified for both Piz and Piz-t gene. But japonica type, Gerdeh, possessed only Piz gene between Piz and Piz-t. Fifty two accessions showed the three of Pik multiple genes and Pit gene. Four accessions, Iari7447, Daebunhyangdo2, Shiyayuuine, and Basmati 6129 possessed a Pik-p gene. Especially, Pit gene on chromosome 1 was detected with t256 marker in all of 83 accessions, exception of A-2, one accession of japonica type.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.100-105
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• 2001

One-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis (1D SDS-PAGE) was used to determine whether it would provide improved resolving power of hordein proteins concomitant with improved identification of Korean barley cultivars and germplams. This system gave rapid and reproducible separations of hordein polypeptides. Total fourteen of clear and easily scorable subunits were identified in Korean barley cultivars and germplasms and their polymorphic constitutions could provide biochemical genetic information in progeny analysis and endosperm quality improvement in barley breeding programs. Each hordein polypeptides residing in B, C, and D hordein pattern designations were scored to prepare a cultivar catalogue of protein patterns. On the basis of this character, 7 hordein polypeptide patterns were constructed from 108 barley cultivars and experimental lines. The molecular weight of hordein subunits in Korean barley cultivars and experimental lines varied in the range of 98 to 48 kDa. In contrast, less polymorphic hordein polypeptides were found in the low protein barley lines including malting barleys than those found in Korean barley cultivars and experimental lines.