• Asian Journal of Turfgrass Science
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• v.20 no.1
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• pp.1-10
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• 2006

This study was carried out to develope new zoysiagrass cultivar 'Millock'(Patent registration No. : 10-2005-0110051). Artificial selfing of collected line of MJ8 was conducted to develope F1 plant (MJ8S). Among the inbred progenies, MJ8S-9 (Millock) showed superior performance in color, density, and rust resistance. 'Millock' showed genetically dark green color, with medium-textured leaf ($4.2{\pm}0.44$ mm), short internode length ($3.5{\pm}0.28$ cm), and wide leaf angle ($52.5{\pm}10.8$ degree). Height to the lowest leaf blade of this cultivar was $1.9{\pm}0.91$ cm, which may allow low mowing height. 'Millock' has a yellowish green stolen. Also, specific bands with primer number OPB 8 by RAPD analysis can be used for a cultivar identification.

• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.475-478
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• 2000

The cytosolic glutathione reductase(GR) gene of chinese cabbage was introduced into Lettuce (Lactuca sativa L.) with particle bombardment method. When cotyledon explants were treated with osmoticum-conditioning medium (0.6 M sorbitol/mannitol) 4 hours prior to and 16 hours after bombardment, it was identified by GUS assay that this condition was the most efficient one for introduction of foreign genes into cotyledon tissue of lettuce with particle bombardment. The stable integration of a GR gene was confirmed by the PCR analysis. 0.3, 0.6, 1.5 kbp PCR fragments of transgenes were obtained by three types of primers designed on the basis of GR sequence. To know whether the expression of the GR gene of pBKs-GR 1 can be stably maintained in the next generation, T$_2$selfing seeds obtained from the transformed mother plants were sowed on MS medium supplemented with 200 mg/L kanamycin sulfate. 70% of seedlings showed resistance to kanamycin.

• Research in Plant Disease
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• v.11 no.2
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• pp.106-114
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• 2005

To breed powdery mildew resistant varieties, 104 accessions of Cucurbita spp. germplasm were evaluated. Powdery mildew resistance and horticultural characteristics of the accessions were investigated in the field conditions. C. martinezii was selected for high resistance to powdery mildew in the field. The growth of powdery mildew pathogen and response of leaf surface tissue to the pathogen were observed after artificial inoculation to resistant C martinezii and susceptible C. moschata cv. 'Wonye No.402'. Mycelium growth was very clearly different between resistant C. martinezii and susceptible C moschata cv. 'Wonye No. 402' at 5 days after inoculation at the adult stage. Interspecific hybridization was attempted to transfer powdery mildew resistance gene(s) from C. martinezii to C. moschata. A single dominant gene action was postulated as deter mining powdery mildew resistance at the seedling stage. But for the effective selection of powdery mildew resistant individuals, it was established that adult plant resistance should be confirmed in the field conditions after the seedling test. Through the seedling and field tests, C. moschata lines resistant to powdery mildew and superior to horticultural characteristics, were selected after 2 backcrossing and 3 selfing generations. The fruit characteristics of newly developed lines were similar to those of the recurrent parent, 'Jaechenjarae'.

• Korean Journal of Plant Taxonomy
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• v.49 no.4
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• pp.324-333
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• 2019

Neutral genetic diversity found in plant species usually leaves an indelible footprint of historical events. Korea's main mountain range (referred to as the Baekdudaegan [BDDG]), is known to have served as a glacial refugium primarily for the boreal and temperate flora of northeastern Asia. In addition, life-history traits (life forms, geographic range, and breeding systems) influence the within- and among-population genetic diversity of seed plant species. For example, selfing species harbor significantly less within-population genetic variation than that of predominantly outcrossers. A previous study of two Liparis species (L. makinoana and L. kumokiri) emphasizes the role of the abovementioned factors shaping the levels of genetic diversity. Liparis makinoana, mainly occurring on the BDDG and self-incompatible, harbors high levels of within-population genetic diversity (expected heterozygosity, H_eP = 0.319), whereas there is no allozyme variation (H_eP = 0.000) in L. kumokiri, which is self-compatible and mainly occurs in lowland hilly areas. To determine if this trend is also found in other congeners, we sampled five populations of L. krameri from the southern part of the Korean Peninsula and investigated the allozyme-based genetic diversity at 15 putative loci. The somewhat intermediate levels of within-population genetic variation (H_eP = 0.145) found in L. krameri are most likely due to its occurrence in mountainous areas that, despite being outside of the main ridge of the BDDG, still served as refugia, and a self-incompatible breeding system. Management strategies are suggested for L. krameri and L. makinoana based on the levels and distribution of genetic diversity and inbreeding.

• Journal of the Korean Society of Tobacco Science
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• v.17 no.1
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• pp.27-32
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• 1995

A new flue-cured tobacco mutant line BU 8832-85 was developed at Taegu Experiment Station, Korea Ginseng and Tobacco Research Institute in 1994. KF 8832-85 was resulted from a cross of flue-cured cultivars NC 95$\times$NC 2326, and developed by a pedigree system of breeding ; initial selection was made by plant type and resistance to bacterial wilt(BW) disease(heudomonas solanaceamm) in the F2 generation under the natural field conditions infested with the pathogen. One white flowered plant was occurred by spontaneous mutation in a certain line among the F3 generatioin while the others were pink. Six plants from the seeds by selfing were selected at the field infested with the pathogen among 240 populations with white flowering in the F4, KF 8832-85 was selected based on yield and leaf quality trials among 6 lines in Fs generation. BCF 8832-85 was compared with its Parent for certain agronomic and chemical characteristics at Taegu Experiment Station in 1993 and 1994. The results showed that KF 8832-85 have white flower, the stalk height was approximately that of NC 2326 but averaged about loom taller than NC 95. It produced ground suckers as much as NC 95, and did not breakdown leaf at the same as WC 2326. KF 8832-85 have high resistance to bacterial wilt disease. Yield of KF 8832-85 was 10 and 18% higher then that of NC 2326 and WC 95, respectively. Price per Kg was equal to that of NC 2326. The contents of nicotine and reducing sugar did not differ significantly from NC 95, while total nitrogen was significantly lower than NC 95. Therefore, the new mutant line is genetically stable for agronomic and chemical characteristics and provides a source of bacterial wilt disease resistance for use in breeding resistant flue-cured cultivars. Key words : Mutant line, White flower, Spontaneous mutation.

• Horticultural Science & Technology
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• v.16 no.2
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• pp.236-238
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• 1998

This study was conducted to investigate the effective media and optimal days after pollination for germination of seeds which were crossed by selfing or reciprocal pollination in Cymbidium spp. The elongation of ovary stopped about 110 days after pollination regardless of cross combinations. The increase of ovary width stopped about 140 days after pollination showing some differences among cross combinations. The cross combinations expressing high capsule number and viability showed good germination when they were sown in vitro. The capsules collected 150 to 180 days after pollination showed good germination performance and short days of germination. Hyponex media was the most effective for protocorm development and germination.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.42-55
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• 1984

The direction of scientific researches on tree improvement and forest management in several universities and research institutes in Japan can be summarized as follows: They put a great emphasis on sugi, Cryptomeria japonica and cypress, Chamaecyparus oblusa which are two major conifer species largerly planted in the Japanese forestry. In the research of sugi, a great concern has been made in evaluating inheritance of forest tree, quantitative characters and genetic parameter of growth, and in breeding for resistance to diseases and insects and to all the natural calamities. Interaction between environmental conditions and genetic nature of tree can be concerned factors in relation with forest damage, together with silvicultural conditions and pest infestation. Selfing hybrids of $F_1$ made from crossing twisted-leaf sugi, defomity leaf type and midori sugi, normal leaf type segregated the normal needle, twisted needle, green leaf and albino leaf type. It seemed that separation of many defomity individuals can be governed by two dominant complementary genes and from the near loci of which it was detected lethal genes. 52% of Japanese forestry is occupied by the small forest landowners like Korean forestry. This made difficulty for forest improvement such as progressive afforestation and for capital accumulation form forestry. The Forest Corporation was established at first in 1959 to aming at productive forestry structure and forest management, and afforestation. For these purpose, 35 Forest Corporations are at moment operating throughout Japan. However, investment in forestry business becomes less attractive since the wage in forest production duction increased in higher trend. than timber price. Therefore, an artifical afforestation becomes yearly decreased. At present. the self-sufficient rate of timber production in Japan is about 35%, and so a great effort is being made to increase self-sufficient rate of timber production.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.277-283
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• 2010

Rape (Brassica napus L.) plants are one of the major oilseed crops. The main components of rapeseed are oil (35 to 47%) and protein (15 to 32%). For the biodiesel production, the development of a new variety of rape plant with high biomass and/or oleic acid contents is required. In order to determine the optimum dose of gamma-ray irradiation, the rape seeds of cvs. Hanra (Hr), Youngsan (Ys), Tammi (Tm), and Tamra (Tr) were irradiated with a 100~4,000 Gy dose range of gamma-rays. Considering the growth factors, the optimum doses were determined to be within the range of 600~1,000 Gy for the selection of useful mutant lines. Six-hundred and eighty-eight (688) $M_2$ mutant lines were obtained from 600~1,000 Gy gamma-ray-irradiated $M_1$ plants through selfing. The growth characteristics, leaf shape, early flowering, and flower color were all investigated. The selected mutant numbers of early flowering, leaf shape, and flower color were 34, 52, and 3 from the four cultivars, respectively. These mutant lines will be used for the development of a new variety of rape plant with high biomass and oleic acid contents.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.324-327
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• 2009

The white flowered 'Eorayeon 1ho' is the first Kangwon National University cultivar of L. ${\times}$ formolonga, commonly known as seed propagating lily. Crosses were conducted from 1999 to 2003 among the selected selfing lines($S_3$) of L. longiflorum 'Lorina', L. ${\times}$ formolonga 'Augusta' and 'Raizan Herald'. A new cultivar was preliminarily selected as 'E-No.1' in 2003 for its stable upward flowering habit. The evaluation of characteristics was investigated from 2003 to 2004 in Chuncheon and Yungweol, Kangwon province. 'Eorayeon 1ho' blooms in early July at outside, with high resistance to Botrytis and having upward flowering habit. The plant height is 112.4 cm and the percentage of seed germination is 96.4%. This seed propagating cultivar shows good quality as a cut flower and low blasting rate.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.4
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• pp.443-451
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• 2021

Finger millet (Eleusine coracana) is widely cultivated in tropical regions worldwide owing to its high nutritional value. Finger millet is more tolerant against biotic and abiotic stresses such as pests, drought, and salt than other millet crops; therefore, it was proposed as a candidate crop to adapt to climate change in Korea. In 2019, we used expressed sequence tag simple sequence repeat (EST-SSR) markers to evaluate the genetic diversity and structure of 102 finger millet accessions from two geographical regions (Africa and South Asia) to identify appropriate accessions and enhance crop diversity in Korea. In total, 40 primers produced 116 alleles, ranging in size from 135 to 457 bp, with a mean polymorphism information content (PIC) of 0.18225. Polymorphism was detected among the 40 primers, and 13 primers were found to have PIC values > 0.3. Principal coordinate and phylogenetic analyses, based on the combined data of both markers, grouped the finger millet accessions according to their respective collection areas.Therefore, the 102 accessions were classified into two groups, one from Asia and the other from Africa. We have conducted an in-depth study on the finger millet landrace pedigree. By sorting out and using the molecular characteristics of each pedigree, it will be useful for the management and accession identification of the plant resource. The novel SSR markers developed in this study will aid in future genetic analyses of E. coracana.