• Horticultural Science & Technology
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• v.34 no.3
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• pp.433-441
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• 2016

Clubroot caused by the protist Plasmodiophora brassicae is one of the most destructive diseases of Brassica crops. Developing Chinese cabbage cultivars with durable clubroot resistance (CR) is an important goal of breeding programs, which will require new genetic resources to be identified and introduced. In this study, we evaluated resistance to P. brassicae race 4 using 26 Chinese cabbage (B. rapa ssp. pekinensis ) cultivars compared to the clubroot-susceptible Chinese cabbage inbred line 'BP079' and the clubroot-resistant European turnip (B. rapa ssp. rapifera ) inbred line 'IT033820'. No symptoms of clubroot disease were found in 'IT033820' infected with P. brassicae race 4, whereas the Chinese cabbage cultivars exhibited disease symptoms to various degrees. The Chinese cabbage cultivars that were reported to be clubroot-susceptible were susceptible to P. brassicae race 4; however, seven of the 20 cultivars reported to be clubroot-resistant were susceptible to this race of P. brassicae to varying degrees. Resting spores of P. brassicae were abundant within the infected root tissues of 'BP079', as revealed by light microscopy and scanning electron microscopy (SEM), but they were not detected in root tissues of 'IT033820'. Although resting spores were not detected by light microscopy in root tissues of the clubroot-resistant Chinese cabbage cultivar 'Kigokoro 75', a few spores were observed by SEM. The $F_1$ hybrids from a cross between 'IT033820' and 'BP079' showed no disease symptoms, and all $BC_1P_1$ progenies from a cross between the $F_1$ hybrid and 'IT033820' exhibited a resistance phenotype. In the $BC_1P_2$ population from a cross between the $F_1$ hybrid and 'BP079', this trait segregated at a ratio of 3(R):1(S) (${\chi}^2=1.333$, p = 0.248) at a 5% significance level. Inoculated $BC_1P_2$ plants were either highly resistant or highly susceptible to the pathogen, indicating that the CR to race 4 of P. brassicae carried by 'IT033820' is dominant. In the $F_2$ population, this trait segregated at a ratio of 15(R):1(S) (${\chi}^2=0.152$, p = 0.696) at a 5% significance level, suggesting that CR in 'IT033820' is mainly controlled by two dominant genes. Therefore, 'IT033820' represents a promising genetic resource for developing durable CR breeding lines in Chinese cabbage.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.180-183
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• 2011

'Yeomyeong', a new welsh onion (Allium fistulosum L.) variety, is developed by the Bioenergy Crop Research Center, NICS, RDA in 2004. This variety, as interspecific $F_1$ hybrid, is developed by a cross between onion (Allium. cepa L.) and welsh onion (A. fistulosum L). The first cross was conducted in 2003 between MOS8, onion male sterile line and G2, welsh onion inbred line. Horticultural and yield characteristics of this hybrid $F_1$ line was investigated in greenhouse for 2 years from 2004 to 2005 with fall cropping cultivation. It has a single pseudostem plant type, anthocyanin-colored pseudostem, and male sterile umbel. It showed intermediate plant type of the maternal parents in overall plant characteristics. 'Yeomyeong' is fall sawing variety and has higher plant height and pseudostem length than that of check variety 'Gumjang'. The yield potential of this variety was about 130.1MT/ha in greenhouse in spring harvseting season. This variety would be adaptable to the fall sowing cultivation in green house.

• FLOWER RESEARCH JOURNAL
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• v.17 no.4
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• pp.328-331
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• 2009

The white flowered 'Eorayeon 2ho' is a cultivar of Lilium ${\times}$ formolonga developed in Department of Horticultural Sciences, Kangwon National University, Chuncheon, Korea. $F_1$ hybrid LA-77 was selected from the cross between a selected selting line($S_3$) of L. longiflorum 'Lorina' and a selfing line($S_3$) of L. ${\times}$ formolonga 'Augusta' in 2000. The $F_1$ hybrid LA-77 was backcrossed by a selected line of L. ${\times}$ far molonga 'Raizan No. 1' from 2001 to 2002. 'MF-No.2' was preliminarily selected for its upward flowering habit and high plant height. The evaluation of characteristics was investigated from 2003 to 2004 in Chuncheon and Yungweol, Kangwon province. 'Eorayeon 2ho' blooms in early July at outside, with high resistance to Botrytis and showing upward flowering habit. The plant height is 132.6 cm and the percentage of seed germination is 95.3%. Mean tepal length and width are 16.0 em and 4.3 cm, respectively. The length and width of leaf is 12.3 and 3.2 cm, respectively. This seed propagating cultivar shows high plant height suitable for a cut flower.

• Korean Journal of Breeding Science
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• v.43 no.6
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• pp.559-563
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• 2011

Cymbidium 'Purple Star' (Miake 'Pieta' ${\times}$ 'Allstar Mariane') was developed from a cross between hybrids at the National Institute of Horticultural & Herbal Science (NIHHS), Rural Development Administration (RDA) in 2008. A cross was made between purple colored flower C. Miake 'Pieta' as maternal line and dark pink colored flower, C. 'Allstar Mariane' as paternal line in 1995. The seed germination, cultivation, selection, and characteristic trials were conducted from 1996 to 2002. The line was named as Wongyo 'F1-21' and phenotype was characterized in 2007 as a new cultivar. The 'Purple Star' has dark purple basal color (RHS, GP186A) on both of sepal and petal with red lip (RHS, RP59A). 'Purple Star' has about 10.7 flowers per flower stalk and flower size of 7.6 cm. General appearance of petals and sepals is slightly incurved shape. The plant size is intermediate having erect peduncle. Blooming is started from the late of January (mid-winter) under optimal culture condition. Leaf attitude and twisting is erect and weak respectively. This hybrid has attractive floral arrangement, long flower stalk (78.4 cm) and vigorous growth. 'Purple Star' has a great potential for exporting to Chinese market.

• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.298-317
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• 2019

A statistical analysis of 9,771 non-glutinous rice in breeding line germplasm collected from Korea (2,836), China (2,136), Japan (1,219), and the Philippines (1,213) was conducted using normal distribution, variability index value (VIV), analysis of variation (ANOVA) and Ducan's multiple range test (DMRT) based on the data obtained from NIRS analysis. According to the normal distribution, the average protein content was 7.9%, and non-glutinous rice ranging over 10% amylose had 23.6% average content. Most resources were between 5.3 and 10.5% in protein content, and 15.7 and 31.5% in amylose content. The VIV was 0.54 for protein, and 0.83 for amylose. The average amylose content was 25.18%, 24.54%, 22.08%, and 21.47% in Filipino, Chinese, Korean, and Japanese resources, respectively, wheereas the average protein content was found to be 8.19%, 7.79%, 7.58%, and 7.42% in Filipino, Chinese, Korean, and Japanese resources, respectively. The ANOVA of amylose and protein content showed significant differences at the level of 0.01. The F-test value was 412.2 for amylose content, and 108.4 for protein when compared with the critical value of 3.78. The DMRT of amylose and protein content showed significant differences (p<0.01) among resources from different countries. The Filipino resources had the highest level of amylose and protein content, whereas; the lowest level of amylose and protein content were found in Japanese when compared with resources of other origins. These results are recommended as helpful materials in the field of breeding.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.10
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• pp.1417-1425
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• 2014

The selection of morphologically normal spermatozoa is critical to obtain high breeding performances in boar breeding farms and artificial insemination (AI) centers. Parameters for the selection of semen mainly include total sperm motility, concentration, and morphology. However, these primary parameters are often not reliable for discriminating between normal and abnormal, non-fertilizable spermatozoa. The present study was designed to compare the motion characteristics, fertilization ability using in vitro fertilization (IVF), and acrosome formation of the semen from boars having low (boar number 2012) and normal (boar number 2004 and 2023) breeding performances. The ultimate goal was to identify additional simple and easy criteria for the selection of normal sperm. There was no significant difference between boar 2004 and boar 2023 sperm total motility in computer assisted sperm analysis. However, boar number 2012 semen presented a significantly reduced population of rapid moving spermatozoa and an increased population of slow moving spermatozoa compared to boar numbers 2004 and 2023. Analysis of detailed motion characteristics revealed that sperm from boar number 2012 had significantly reduced motility in progressiveness, average path velocity, straight-line velocity (VSL), curvilinear velocity (VCL), straightness, and linearity. The assessment of the fertilizing ability by IVF also showed that sperm from boar number 2012 showed a fertility rate of 3.4%, whereas sperm from boar number 2023 had a fertility rate of 75.45%. Interestingly, most of the sperm nuclei were found on the peripheral area of the oocytes, suggesting that the sperm from boar number 2012 lacked penetration ability into the oocyte zonapellucida. The acrosome formation analysis using Pisum sativum agglutinin staining demonstrated that the sperm from boar number 2012 had a defect in acrosome formation. Consequently, primary parameters for selecting semen before AI such as motility are not sufficient to select normal and fertilizable spermatozoa. In conclusion, the present study suggests that the acrosome staining and detailed motion characteristics such as progressiveness, VCL, and VSL should be included in determining semen quality together with primary parameters for successful AI and high breeding performance in the swine industry.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.483-492
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• 2019

During the breeding season, both adults and immature Eurasian Oystercatchers (Haematopus ostralegus osculans) were observed to feed on prey, such as gastropods (Umbonium thomasi) and bivalves, at the tide water line around Yubu island in Korea. To determine differences in the foraging efficiency between the adult and immature birds, we recorded the feeding behavior using digiscoping with a telescope and a smartphone. We compared the pace, the prey search rate, the proportion of prey search techniques, the feeding success rate, the handling time, and the heads-up rate between the adult and immature birds. There were significant differences in the proportion of prey search techniques when gastropods were consumed and in the prey search rate and heads-up rate when bivalves were consumed but there were no significant differences in feeding success rates. Therefore, although the immature birds on Yubu Island were inferior to adults during the breeding season and they lacked the proficiency to locate prey, their overall foraging efficiency was similar to adults. This was considered to be due to the continuous eating of bivalves during the wintering season, which requires a high level of foraging efficiency.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.568-573
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• 2009

A new soybean variety, "Singang", was released by NICS, RDA in 2008. It is resistant to soybean mosic virus (SMV), which is one of the most serious diseases in soybean production. "Singang" had been developed for seven years by molecular marker-assisted selection (MAS) breeding method using recurrent parent, "Sowon", and donor parent, "L29" which has the SMV-resistance gene, Rsv3. Selected promising breeding line, Suwon 242, was evaluated in yield trials for 2 years from 2005 to 2006 at NICS. Regional yield trials were performed for 3 years from 2006 to 2008 in five locations including Jeju. Agronomic characteristics of "Singang" is a determinate growth habit, purple flower color, grey pubescence, yellow testa, light brown hilum and lanceolate leaflet shape. "Singang" showed the similar performance to "Sowon" cultivar. This variety showed 3 days shorter in days to maturity than the check variety (Pungsannamul). The average yield under regional yield trials in five location was 2.78t/ha. It is adaptable to the whole country except for Gangwon province.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.461-465
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• 2008

"Green King" is a new mini kiwifruit variety developed at the National Institute of Subtropical Agriculture (NISA), RDA in 2005, which was an edible fruit without peeling. This variety was selected from seeds obtained from the cross breeding between Actinidia chinensis cv. "Apple Sensation" and A. arguta in 1998. Seedling and line selections were conducted from 1999 to 2002, and characteristic trials were carried out from 2003 to 2004. The branch of "Green King" sprouts strongly and the color of leaf is slightly dark green. The shape of fruit is cylindric and the color of peel is green or yellowish green without hair. The average weight of fruit is 15.9 g. The core is small and soft, the pericarp is light green. Soluble solids concentration is $15.4^{\circ}Brix$. The fruit is sweet with slightly acid taste, containing total acid 1.3%, and the yield is higher over twice than that of A. arguta. The content of vitamin C is higher than that of A. arguta. The harvesting time is from middle October. This variety can be planted in the central and southern region of Korea.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.248-251
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• 2010

A lemon double freesia (Freesia hybrida Hort.), 'Shiny Lemon' was developed from a cross between the domestic breeding lines ('Golden Crown' and 'White Wings') and 'Yvonne' followed by seedling and line selections at the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA) in 2007. Growth and flowering characteristic tests were conducted from 2003 to 2006. 'Shiny Lemon' has large double type flower with lemon color (RHS Y13D). It has multiple florets, good flower shape, and upright leaves and stalks. The average cut flower yield of 'Shiny Lemon' was 7.1 cuttings per plant in the greenhouse from 2005 to 2007. Additionally, it has good production of cormlets and vigorous growth. 'Shiny Lemon' could be cultured under greenhouse conditions in Korea.