• Asian-Australasian Journal of Animal Sciences
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• v.30 no.9
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• pp.1234-1238
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• 2017

Objective: The vertebral number is associated with body length and carcass traits, which represents an economically important trait in farm animals. The variation of vertebral number has been observed in a few mammalian species. However, the variation of vertebral number and quantitative trait loci in sheep breeds have not been well addressed. Methods: In our investigation, the information including gender, age, carcass weight, carcass length and the number of thoracic and lumbar vertebrae from 624 China Kazakh sheep was collected. The effect of vertebral number variation on carcass weight and carcass length was estimated by general linear model. Further, the polymorphic sites of Vertnin (VRTN) gene were identified by sequencing, and the association of the genotype and vertebral number variation was analyzed by the one-way analysis of variance model. Results: The variation of thoracolumbar vertebrae number in Kazakh sheep (18 to 20) was smaller than that in Texel sheep (17 to 21). The individuals with 19 thoracolumbar vertebrae (T13L6) were dominant in Kazakh sheep (79.2%). The association study showed that the numbers of thoracolumbar vertebrae were positively correlated with the carcass length and carcass weight, statistically significant with carcass length. To investigate the association of thoracolumbar vertebrae number with VRTN gene, we genotyped the VRTN gene. A total of 9 polymorphic sites were detected and only a single nucleotide polymorphism (SNP) (rs426367238) was suggested to associate with thoracic vertebral number statistically. Conclusion: The variation of thoracolumbar vertebrae number positively associated with the carcass length and carcass weight, especially with the carcass length. VRTN gene polymorphism of the SNP (rs426367238) with significant effect on thoracic vertebral number could be as a candidate marker to further evaluate its role in influence of thoracolumbar vertebral number.

• Journal of Korean Society for Atmospheric Environment
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• v.32 no.6
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• pp.593-602
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• 2016

The physicochemical characteristics of particulate matter emissions from various vehicle's fuel types were studied at the facility of Transport Pollution Research Center(TPRC), National Institute of Environmental Research (NIER), Korea. Three different types of fuels such as gasoline, liquefied petroleum gas (LPG) and diesel were tested on the NIER driving mode and the constant speed modes(30, 70, and 110 km/h). Chemical composition of submicron particles from vehicle emissions was measured by the High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) during running cycles. Organics were dominant chemical species of particulate matter emissions for all three different vehicles' fuel types. Moreover, regardless of fuel types, emission rate of organics and inorganics decreased as the average speed of vehicle increased. The portion of fully oxidized fragment families of $C_xH_yO_z$ accounted for over 98% of organic aerosol(OA) in LPG and diesel vehicles, while the relatively high fraction of $C_xH_y$ in OA was observed in gasoline vehicle.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.11-19
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• 2003

The life-cycle of the aphid-parasite, Aphidius gifuensis, took 11.9 days at $25^{\circ}C$ and 12.1 days at $30^{\circ}C$. The female appearance rate of A. gifuensis was the best at $20{\sim}25^{\circ}C$ compared to the other temperatures. Optimum rearing temperature of Aphidius gifuensis was $20{\sim}25^{\circ}C$ Optimum temperatures for A. gifuensis emergence were $20^{\circ}C$ and $25^{\circ}C$ with 99.1% and 98.2%, respectively. However the emergence rate of Aphidius gifuensis was 58.8% at $10^{\circ}C$. There was a positive correlation between A. gifuensis adult activity and temperature, but there was a negative correlation between developmental period of Myzus persicae nymph and temperature. Among the pests occurring in pepper greenhouse, dominant species was M. persicae and its density was 6~1,024 per plant. The damaged fruit rate by Helicoverpa assulta was 3.3~53.3%. The number of aphid and mummy in the A. gifuensis released plot were 173.5 and 10 in June, 1.8 and 17 in July, 2000, respectively. The numbers of Aphidius gifuensis were 7.5 and 0.4 in May, 27.1 and 2.1 in June, 2001, respectively. The suppressive effects on M. persicae in A. gifuensis released plot was better than the control plot, but there was no significant difference compared to the pesticide-sprayed plot. The first leaf length and the stem width in the A. gifuensis released plot, the control plot, and the pesticide-sprayed plot were not significantly different, but the A. gifuensis released plot showed the highest yield among the plots.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.376-385
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• 2016

Through the vegetation survey of Geumcheon Valley on the south-facing slope and the other side of the valley, Jedanggol on the north-facing slope in Taebaeksan Provincial Park, the characteristics of vegetation structure and change by slope and altitude were examined. From Geumcheon Valley(850m) via the ridge(1,380m) to Jedanggol(950m), thirty plots at intervals of 50m altitude were selected for investigation. According to the results of the analysis, Acer pictum subsp. mono, Fraxinus rhynchophylla, Betula davurica and Lindera obtusiloba were observed only in the south-facing slope, while Sorbus commixta, Prunus padus, Prunus maackii and Acer komarovii were observed only in the north-facing slope. However, Quercus mongolica, Betula costata, Cornus controversa, Tilia amurensis, Acer pseudosieboldianum and Magnolia sieboldii were found to be distributed over both the slopes. The analysis of ordination found that the vegetation was distributed discontinuously by slope. Especially, the vegetation of the north-facing slope appeared to be affected by the direction that the slope faces. Quercus mongolica community, which is the dominant species at an altitude of over 1,200m, was determined to be affected by elevation factor. The maximum age of the major trees was as follows: Betula costata and Quercus mongolica were estimated to be 53-year-old and 113-year-old respectively.

• The Korean Journal of Ecology
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• v.16 no.4
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• pp.489-499
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• 1993

Drifting aquatic insects were collected with using drift nets in the middle reaches of the Paenae stream. a tributary of the Naktong River in Korea, in four seasons from August 1989 to May 1990. During the study period, 6 orders and 31 families were collected. Drifted insects were the most diverse in autumn, while the number of collected individuals was the highest in spring. The abundant groups were the primary consumers such as Ephemeroptera and Diptera including Heptagenidae, Baetidae, and Chironomidae. The secondary consumers such as Plecoptera and Trichoptera, and the burrowers, Ephemeridae and Odonata were collected less than the primary consumers. Generally the first dominant species belonged to Ephemeroptera such as Pseudocloeotz sp., Heptagenia sp., and Baetis sp, In four seasons Ephemeroptera appeared more abundantly in drift(62%) than benthic samplings(33%). Diptera occurred similarly in drift and benthic samplings at 22%. Plecoptera and Trichoptera were collected at 4% and 11%, respectively, and appeared less than in benthic samplings. In functional groups collectors and scrapers were collected more than shredders and predators in drifts. In habit groups clingers and swimmers were present more than sprawlers and burrowers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.419-423
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• 2003

Bacterial blight caused by Xantomonas oryzae pv. oryzae is one of the most serious diseases of rice especially in southern area of Korea. Three races, $\textrm{K}_1$, $\textrm{K}_2$ and $\textrm{K}_3$, are the most dominant species. lo improve rice breeding efficiency using marker assisted selection, some RFLP markers were surveyed for polymorphism between resistant and susceptible to $\textrm{K}_1$ and $\textrm{K}_3$. And, 127 doubled-haploid (DH) lines derived from Milyang121/HRl1650-1-4-2 and 131 DH lines derived from Milyang123/HR10624-AC5 were evaluated to bacterial blight ($\textrm{K}_1$ and $\textrm{K}_3$). Milyang121 and HR10624-AC5 have Xa-1, resistant to $\textrm{K}_1$ race, and Milyang123 has Xa-3, resistant to $\textrm{K}_1$ and $\textrm{K}_3$ race. Three markers, RZ590, RZ536 and RG303, showing polymorphism between parents and resistance gene, Xa-1 and Xa-3, were analysed in the two combinations of DH lines. The segregation pattern of resistant DH population of Milyang123/HR10624-AC5 to susceptible showed 3:1 and 1:1 in $\textrm{K}_1$ and $\textrm{K}_3$ race. In three RFLP markers, RZ590 was linked to Xa-1 on chromosome 4, and RZ536 and RG303 were linked to Xa-3 on chromosome 11. The map distance between Xa-1 and RZ590 was 3.1cM on chromosome 4, and Xa-3 and RZ536/RG303 were 7.6/16.0cM on chromosome 11, respectively. The results of RFLP mapping will be useful for the selection and pyramiding of bacterial blight resistant genes.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.223-236
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• 2003

The vegetation in this study area was divided into 10 plant communities: Pinus thunbergii, P. densiflora, Quercus acutissima, Q. mongolica, Q. serratea, Q. variabilis, Q. aliena, Q. dentata, Carpinus coreana, Betula davurica and 3 afforestations; Pinus rigida, Robinia pseudo-acacia, Castanea crenata. The dominant species in each stratum as determined by R-NCD appeared to be Q. acutissima, P. densiflora, Platycarya strobilacea, Sorbus alnifolia and Q. aliena in the tree-2 layer, Rhododendron mucronulatum, P. strobilacea, Q. serrata, Q. aliena and Q. acutissima in the shrub layer, and Carex lanceolata, C. humilis, R. mucronulatum, Mischanthus sinensis var. purpurascens and Oplismenus undulatifolius in the herb layer. The distribution of diameter at breast height(DBH) showed the highest percentage (56%) in the range of 2∼10㎝ in the study area and it was investigated as being in the restoration phase after disturbance. The average of the age of trees was under 40-years-od. The pH of soil collected at each site appeared to be within the range between 4.53 and 5.10(the average of 4.73) in each community, organic matters appeared higher than the value in Q. mongolica, P. rigida, C. crenata communities compared to P. thunbergii, P. densiflora communities. And soil organic matters and total nitrogen were highly correlated with their contents.

• Journal of Korean Society of Forest Science
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• v.84 no.4
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• pp.447-455
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• 1995

Regeneration process of a mongolian oak forest in Bukam-Ryeong area, Mt. Jumbong, Kangwon-Do, was studied in relation to its structure. The dominant trees of the stands came up beyond 10m in height. The upper-tree layer was highly dominated by oaks, and they distributed horizontally in random. Oak trees of the middle layer and the lower layer were few in number and small in basal area, and tended to be distributed contagiously. In the trees of the upper layer, the distribution of the age tended to be two modal type which has the mode of 70 and 230 years in plot. In the horizontal distribution of these trees, some of the even-aged cluster which were constituted of several trees, were found. The rate of the stern diameter increment during first 25 years of the oaks in upper layer were higher than those of the same species in the middle layer. These results showed that after the forest canopy had been broken out, the seedlings which were established in dense there grow with the decreasing density and some of these, of which distribution became in random, would constitute the canopy.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.422-428
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• 2016

Ginkgo (Ginkgo biloba L.) is one of the most appropriate roadside trees because of a good transplantation nature and ability to grow well in urban environment. Ginkgo is a dioecious species. Sex discrimination of ginkgo is possible through comparing morphological characters of reproductive organs. However, it needs more than about twenty years for reproductive organs to appear after sexual maturity. Until now, ginkgo trees for roadside plantation have been planted without discriminating the sex because ginkgo trees have been usually planted before sexual maturity. Ginkgo nuts from the female ginkgo trees planted along the roadside emit a foul odor, and make much pollution on the streets. Thus in this study a novel SCAR marker (SCAR-GBM) for the early sex discrimination was developed. Primers were developed on the basis of the sequence of male-specific RAPD variants reported previously. False-negative problem of SCAR marker, probably caused by dominant nature, was resolved by using multiplex PCR using primers of both the SCAR-GBM and a universal primer set of atp1 region in mitochondria DNA, which resulted in improved discrimination efficiency. The results showed that DNA bands of 1,039 bp were commonly amplified by the atp1 primer set in male and female trees, and SCAR-GBM markers of 675 bp were specifically amplified only in male trees. Reproducible and specific discrimination of the multiplex PCR was finally confirmed by applying multiple male and female individuals.

• Development and Reproduction
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• v.4 no.1
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• pp.87-93
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• 2000

Equine chorionic gonadotropin (eCG) consists of highly glycosylated noncovalently linked $\alpha$- and $\beta$-subunits and belongs to the glycoprotein hormone family that includes lutropin (LH), follitropin (FSH), and thyrotropin (FSH). eCG is a unique member of the gonadotropin family because it elicits response characteristics of both FSH and LH in other species than the hone. eCG is synthesized and secreted by trophoblastic cells of the endometial cups between 40 and 130 days of gestation. In the present study, mRNA expression ratio of eCG, eLH and eFSH $\alpha$- and $\beta$-subunints was investigated in the placenta and pituitary. mRNA was extracted from equine placenta on day 70 of gestation and from pituitary of male horse (27 month-old). When the expression of both subunit mRNAs of eCG in the equine placenta was compared by Northern blotting, the expression of the $\beta$ -subunit mRNA was relatively greater than that of the $\alpha$-subunit. And mRNA expression of $\alpha$-, LH $\beta$- and FSH $\beta$-subunits was analysed in the equine pituitary. An $\alpha$-subunit was revealed with a size of approximately 0.8 kb. FSH $\beta$-subunit mRNA also was detected out 1.8 kb. It is the same size of the FSH $\beta$ -subunit mRNA cloned. The intensity of $\alpha$-subunit mRNA was greater than that of the $\beta$-subunit suggesting that the expression of $\alpha$ -subunit was dominant in the equine anterior pituitary. Thus, the subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$- and $\beta$-subunits in the equine placenta and pituitary.