• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.118-125
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• 1978

To find out highly resistant gene source to black rot fungus in sweetpotato varieties, a screening test was carried out with inoculated tubers and sprouts in 1976 and 1977. Fifteen varieties out of 165 and 54 varieties out of 161 were highly resistant to black rot in the tuber and sprout tests. respectively. The sprout test showed bigger variation from year to year compared to tuber test. Varieties highly resistant to black rot in both tuber and sprout tests were Suweon # 59, #81, #90, Norin #17, #23. Chilship-il cho, Sachun Jong #36, Hamkao, and Kandee.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.437-441
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• 1993

The improvement of superior black soybeans could be accomplished through maintenance and use of black soybean collections. A collection of 965 black soybean lines currently grown by farmers was made in 197 locations on spring, 1991. This study was carried out to evaluate them as useful germplasm. Seed characteristics of black soybean collections were evaluated for black soybean breeding for seed quality. The 100-seeds weight of 929 black soybean genotypes were distributed from 6.9 to 48.1 gram. The maximum and minimum 100-seeds weight were derived from Chungnam and Jeonbuk province, respectively. l00-seeds weight was heavier in middle and late maturity group, as maturity was later, whereas no tendency was shown in early maturity group. Length, width and thickness of the collected black soybean seeds were 9.5$\pm$1.5mm, 7.3$\pm1.3mm and 7.3$\pm1.2mm, respectively. Black soybean collections with yellow seed embryo was 72% and the others were green seed embryo.

• Journal of Embryo Transfer
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• v.26 no.3
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• pp.187-193
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• 2011

This study was carried out to establish most suitable freezing condition, to evaluate the different glycerol concentration of freezing and thawing rates on motility, viability, membrane integrity and acrosome intecrity of frozen Korean Jeju Black Bull spermatozoa, Semen was collected from a Korean Jeju Black Bull using an artificial vagina and transported to the laboratory. The semen was extended gradually 1:5 then cooled slowly for 2 hrs to 4$^{\circ}C$. The semen was diluted 1:1 with cryoprotectant extenders (3%, 5% and 7% glycerol) and equilibrated for 2 hrs at cold chamber and packed to 0.5 ml straws. The semen straws were located above 3 cm of liquid nitrogen for 5 minutes, above 5 cm for 10 min and above 8 cm for 10 min. And then the frozen straw was plunged into LN$_2$. The presented straws were examined the viability and motility after thawed at 37$^{\circ}C$ water bath. The viability and membrane integrity immediately post-thawing were significantly higher in samples frozen in 7% glycerol than 3% and 5% glycerol (p<0.05). After CTC staining to assess acrosome integrity, F pattern was significantly increased, but B pattern was significantly decreased in 7% glycerol (p<0.05). Freezing distance of 5 cm from liquid nitrogen and pre-cooling for 10 min yield better survival and membrane integrity, but not significant difference. However, AR pattern according to CTC staining was significantly decreased in 3 cm for 5 min.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.5
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• pp.432-436
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• 1993

The improvement of superior black soybeans could be accomplished through maintenance and use of black soybean collections. This experiment was carried out to select pure-line from the domestic black soybean genotypes, and survey some agronomic characteristics of the collections. Nine hundred and sixty five lines of black soybeans were collected in 197 locations on spring, 1991. Higher distribution was present in broad leaves, purple flower color and tawny pubescence color which were approximate to be 97, 90 and 98%, respectively. In pod color of black soybean collections, 60% was brown and 27% was light brown and 10% was dark brown. The 61 to 70 days were required for flowering in 61 % of the collections. Growing days of 51 % of black soybean collections ranged 121 to 130, and those of 37 % were over 131 days.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.5 no.1
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• pp.32-37
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• 2009

The emergency diesel generator (EDG) in a nuclear power plant (NPP) shall start within 10 secondss and supply electrical power to engineered safety features within one minute and less if a loss of offsite power (LOOP), A design-basis event, or their combination occur. Each NPP has an EDG set consisting of two diesel generators for redundancy. In addition to the EDG set, an alternate Alternating Current Diesel Generator (AAC DG) is installed and shared by several units to cope with a station black out (SBO), i.e., loss of the offsite power concurrent with reactor trip and unavailability of the EDG set. The objective of this study is to analyze the failure data of emergency diesel generators reported in overseas nuclear power plants.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.5
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• pp.748-754
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• 2018

Objective: The preference evaluation of cattle is an important factor for estimation and improvement of the grazing amounts of newly introduced or bred grasses or cultivars in barn. This study was performed to assess the grazing behavior (the amount of grazing and/or the grazing speed) of cattle as indirect method using newly bred Brachiaria ruziziensis tetraploid strain 'OKI-1'(BR) hay as treatment group and Cloris gayana 'Callide' (CG) hay as control group. It also compared the feasibility of using behavioral differences between two groups as one criteria for evaluating preference by Japanese black cattle in barn. Methods: Three experiments were carried out using 12 growing Japanese Black cattle including 6 males and 6 females. In each experiment, the four Japanese Black cattle (2 males and 2 females) were placed in separated stall and allowed to graze BR and CG in manger that was separated into two portions for about 30 min. The position and behavior of the cattle were recorded, and weighed the residual of each gay at 15 and 30 minutes after experiment start. Results: The BR was superior to CG in chemical composition such as protein, fibers and non-fibrous carbohydrate. The cattle, over all, tended to prefer BR over CG in the first half 15 minutes in terms of the time spent and amount of grazing. Additionally, growing cattle exhibited neophilia for BR bred newly. Conclusion: These findings indicated the current approach could be applied for one of criteria to evaluate the preference of hay by Japanese black cattle under indoor housing environment.

• Journal of Embryo Transfer
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• v.28 no.3
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• pp.207-213
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• 2013

This study was carried out to examine a molecular marker system for parentage test in Jeju Black cattle (JBC). Based on the preliminarily studies, we finally selected for construction of a novel genetic marker system for molecular traceability, identity test, breed certification, and parentage test in JBC and its related industrial populations. The genetic marker system had eight MS markers, five indel markers, and two single nucleotide polymorphisms (SNPs; g.G299T and g.del310G) within MC1R gene which is critical to verify the breed specific genotypes for coat color of JBC differing from those of exotic black cattle breeds such as Holstein and Angus. The results showed lower level of a combined non-exclusion probability for second parent (NE-P2) of $4.1202{\times}10^{-4}$ than those previously recommended by International Society of Animal Genetics (ISAG) of $5.000{\times}10^{-4}$ for parentage, and a combined non-exclusion probability for sib identity (NE-SI) of $2.679{\times}10^{-5}$. Parentage analysis has been successfully identified the JBC offspring in the indigenous population and cattle farms used the certified AI semens for production using the JBC-derived offspring for commercial beef. This combined molecular marker system will be helpful to supply genetic information for parentage test and traceability and to develop the molecular breeding system for improvement of animal productivity in JBC population.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.22 no.2
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• pp.104-111
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• 1977

This study was carried out in order to know the ecological variation and yield factors under the Korea weater with the 25 sunflower varieties which have been introduced from abroad recently. As the results of this of this study we can conclude that high yield and high oil content varieties seemed to have the short period comparatively from planting to head visible and to have long period from flowering to maturity.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.85-89
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• 2012

To investigate the bird's dieting behavior for several fruits in orchards, this study was carried out in 2008. Black-billed magpies (Pica pica), azure-winged magpies (Cyanopica cyanus), and brown-eared bulbuls (Hypsipetes amaurotis) made their unique marks on the surface of pear and apple fruits; black-billed magpies pecked fruits strongly and left round holes with perpendicular angle, whereas those of azure-winged magpies and brown-eared bulbuls were sack-shaped with narrow neck and marked unique stripes on the skin. For the fruits of pear and apple from bagging practices, the birds showed different foraging behavior; black-billed magpies could injure all kinds of fruits whether with paper bags or not, but azure-winged magpies and brown-eared bulbuls could not attack the fruits with paper bag. Azure-winged magpies and brown-eared bulbuls preferred pear fruits to those of apples and satsuma mandarins in the cage trials. To reduce the injuries by azure-winged magpies and brown-eared bulbuls on pear and apple fruit, wrapping bag should not be impaired. Introducing azure-winged magpies to Cheju should be prohibited for the potential citrus injury by them.

• Journal of Animal Science and Technology
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• v.44 no.2
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• pp.207-212
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• 2002

This study was conducted to investigate the genotypes and frequencies of Melanocortin 1 Receptor(MC1R) genes in pigs which plays a central role in regulation of eumelanin (black/brown) and phaeomelanin(red/yellow) pigment synthesis within the mammalian melanocytes. Four different breeds of pigs(20 Landrace, 20 Yorkshire, 20 Duroc, and 93 Jeju native black pigs) were used and PCR-RFLP analysis of MC1R gene was also carried out. Two regions of MC1R genes (428bp and 405bp) were amplified using two specific primers (MERL1-EPIG2, EPIG1-EPIG3), respectively and MC1R allele were determined using 2 restriction enzymes (BspHⅠ, AccⅡ). The results of this experiment indicated that MC1R allelic type in Landrace, Large Yorkshire and Duroc were MC1R *2 (Ep), MC1R *2 (Ep), MC1R *4 (e), respectively. However, various allelic types of MC1R genes were detected in Jeju native black pigs. MC1R allelic type of Jeju black pigs was MC1R*2 type as in Meishan and Large black breeds or MC1R*3 type as in Hampshire and Berkshire breeds and the gene frequencies of ED1 and ED2 were 0.554 and 0.446 in average.