• Korean Journal of Breeding Science
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• v.42 no.1
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• pp.100-108
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• 2010

This study was carried out to confirm the chromosome constitution and homoeologous recombination of progenies derived from various cross combination using tetraploid OA interspecific hybrid originated from mitotic chromosome doubling. Based on the chromosome analysis of progenies crossed reciprocally, there were only triploid progenies when crossed with diploid Asiatics as male or female parent. While only tetraploid progenies were produced when crossed tetraploid Asiatics or tetraploid OA hybrid with tetraploid OA hybrid, respectively. However, two types of progenies, that is, diploid and triploid plants, were produced from cross combinations between diploid Oriental hybrid and tetraploid OA hybrid. From the GISH analysis of OA hybrid, it was confirmed that diploid $F_1$ OA hybrid was consisted of 24 chromosomes (12 Oriental and 12 Asiatics) showing authentic OA hybrid. On the other hand, it was notified that triploid plants (3x=36) were consisted of 24 Asiatics lily chromosomes and 12 Oriental lily chromosomes by analysis of backcross progenies derived from either $A{\times}OA$ or $OA{\times}A$ crosses. In cross between tetraploid OA and OA, all the progenies were tetraploid with equal number of chromosomes without any homoeologous recombination, i.e. each 24 chromosomes of Oriental and Asiatics. In 2x-4x ($O{\times}OA$) cross combination, some progenies had 2x=24 chromosomes originated from only Oriental hybrid, and other progenies had 3x=36 chromosomes derived from 24 chromosomes of Oriental hybrid and 12 chromosomes of Asiatic hybrid. Only tetraploid Asiatics chromosomes without any Oriental one were produced in all the progenies from 4x-4x ($AA{\times}OA$) cross combination.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.695-698
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• 2010

The incidence of Anthracnose causing severe damage to the foliage and fruit in watermelon has increased in some major watermelon producing areas in Korea. To develop anthracnose resistant line, 'AU-Producer' having resistant gene to anthracnose was selected from germplasm and crossed with high quality line '920533'. Following the initial cross, backrossing and disease screening were performed to select resistant lines that produced high yields with excellent quality fruit. As a results of these procedure, a mid maturing watermelon line, 'Hangyeol' with resistance to anthracnose (Colletotrichum orbiculare) race 1 and 3 was developed at the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA). It has red flesh and commonly produces fruit with clear stripes on skin between 5.3 to 10.1 kg. Average soluble solid contents are ranged from 9.8 to 11.8$^{\circ}$Bx. The yield and quality of 'Hangyeol' is comparable to or better than those harvested from the popular commercial cultivars. The achievement of this experiment could contribute to provide the resistant parents in an anthracnose resistance breeding program in watermelon.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.210-213
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• 2011

A dark pink semi-double freesia (Freesia hybrida Hort.) 'Happy Birthday' was bred from a cross between 'Pink Jewel', F1 progeny of 'Michelle' and 'Rossini' as a female and 'White Lace' as a male parent. Test for the growth vigor and flowering characteristic were conducted from 2002 to 2007. A new variety 'Happy Birthday' has semi-double flower type with dark pink color (RHS color chart #RP66C). It has multiple flowers, distinctive flower shape, upright leaves and also stalks. The average yield of this variety 'Happy Birthday' counted over 6.7 stems per plant per season in the standard greenhouse cultivation method. It has also good production of cormlets, vigorous growth. A new variety 'Happy Birthday' is suitable for the greenhouse conditions during winter season in Korea.

• 한국노년학
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• v.37 no.3
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• pp.655-667
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• 2017

This study aimed to identify workplace learning, job satisfaction and geriatric nursing practice, find the correlations between each variable, and investigate affecting factors on geriatric nursing practice. Subjects were 146 nurses in 9 long-term care hospitals including G City, and data were collected from May 1, 2016 through Jun. 30, 2016. Data analysis included independent t-test, one-way ANOVA, Pearson's correlation coefficient and multiple regression using the SPSS/WIN 20.0 program. The results showed that the correlations between each variable showed that incidental learning, a subregion of workplace learning (r=.20, p=.014), and job satisfaction (r=.29, p<.001) had a positive correlation with geriatric nursing practice, respectively. The affecting factors on geriatric nursing practice were job satisfaction, daytime working and nursing experience, and the explanatory power of the model was 20%(F=4.91, p<.001). Based on the results, job satisfaction should be increased to improve the quality of nursing in long-term care hospitals and various methods might be discussed to improve the job satisfaction. Daytime working was suggested one factor on geriatric nursing practice because nursing was provided mainly during daytime, and nursing experience was also one factor on geriatric nursing practice, so highly experienced geriatric nurses could provide high quality elderly patient care.

• Korean Journal of Breeding Science
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• v.50 no.4
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• pp.529-533
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• 2018

Hyowon6, a mid-late maturing, good eating quality rice variety with multi-resistance, was developed by the rice breeding team of Pusan National University in 2013. This variety was derived from a cross between Hwayeong (as a multi-resistant parent) and Koshihikari (as a good eating quality parent). Selection by the pedigree breeding method was carried out until the $F_8$ generation. A promising line, JS14-12-36-8-5-3-1-1-1, was developed and designated as HY103 in 2013. This variety headed on August 22, which was 11 days later than that of Hwayeong. The culm length and panicle length of Hyowon6 was 85.7 cm and 21.1 cm, respectively. The number of panicles per hill was 14.5 and the number of grains per panicle was 101.7. The ratio of ripened grain was approximately 92% and the 1,000-grain weight was approximately 21.36 g for brown rice, which were similar to those of Hwayeong. Hyowon6 was moderately resistant to lodging and also to neck blast, leaf blight, and stripe virus. The glossiness value of Hyowon6 was 83, which was considerably higher than that of Hwayeong.

• Korean Journal of Plant Resources
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• v.37 no.1
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• pp.79-86
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• 2024

This study was conducted to determine the conditions for breaking dormancy in the seeds of the North Korean plant resource, Trollius macropetalus, and to investigate its germination characteristics. The morphological characteristics and viability of T. macropetalus seeds were examined. Germination characteristics were investigated based on temperature conditions (15/6℃ & 25/15℃), cold stratification treatment, and GA₃ treatment. The results showed that cold stratification treatment had no effect on breaking the dormancy of T. macropetalus. GA₃ treatment significantly increased the germination rate of T. macropetalus and also improved the mean germination days and germination speed. However, compared to the 15/6℃ condition, the effectiveness of GA₃ treatment for T. macropetalus decreased under the 25/15℃ condition. It was determined that T. macropetalus have a nondeep-type morpho-physiological dormancy. The most effective conditions for breaking dormancy were found to be the 15/6℃ temperature condition and GA₃ treatment at 500 mg·L^-1. The findings of this study are expected to provide valuable information for the mass propagation of T. macropetalus, which has potential applications in landscaping and pharmaceutical materials.

• Journal of Korean Society of Forest Science
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• v.14 no.1
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• pp.1-20
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• 1972

The trend and achievements of forest genetics research in abroad were investigated through observation tours and reference work and following facts were found to be important aspects which should be adopted in the forest genetics research program in Korea. Because of world wide recognization on the urgency of taking a measure to reserve some areas of the representative forest type on the globe before the extingtion of such forest type as the results of continuous exploitations of the natural forests to meet the timber demand all over the world, it is urgently needed to take a measure to reserve certain areas of natural stand of Pinus koraiensis, Pinus parviflora, Pinus densiflora f. erectra, Abies koreana, Quercus sp., Populus sp., etc. as gene pool to be used for the future program of forest tree improvement. And the genetic studies of those natural forest of economic tree species are also to be performed. 1. Increase of the number of selected tree for breeding purpose. Because of the fact that the number of plus tree at present is too small to carry out selection program for tree improvement, particularly for the formation of source population for recurrent selection of parent trees of the 2nd generation seed orchard it is to be strongly emphasized to increase the number of plus tree by alleviating selection criteria in order to enlarge the population size of plus trees to make the selection program more efficient. 2. Progeny testing More stress should be placed on carrying out progeny testing of selected trees with open pollinated seeds. And particular efforts are to be made for conducting studies on adult/juvenile correlation of important traits with a view to enable to predict adult performances with some traits revealed in juvenile age thus to save time for progeny testing. 3. Genotype-environment interaction Studies on genotype and environment interaction should be conducted in order to elucidate whether the plus trees selected on the good site express their superiority on the poor site or not and how the environment affect the genotype. And the justification of present classification of seed distribution area should be examined. 4. Seed orchard of broad leaf tree species. Due to the difficulty of accurate comparison of growth rate of neighbouring trees of broad leaf tree species in natural stand, it is recommended that for the improvement of broad leaf trees a seedling seed orchard is to be made by roguing the progeny test plantation planted densely with control pollinated seedlings of selected trees. 5. Breeding for insect resistant varieties. In the light of the fact that the resistant characteristics against insect such as pine gall midge (Thiecodiplosis japonensis U. et I.) and pine bark beetle (Myelophilus pinipera L.) are highly correlated with the amount and quality of resin which are known as gene controlled characteristics, breeding for insect resistance should be carried out. 6. Breeding for timber properties. With the tree species for pulp wood in particular, emphasis should be placed upon breeding for high specific gravity of timber. 7. Introduction of Cryptomeria and Japanese Cypress In the light of the fact that the major clones of Cryptomeria are originated from Yoshino source and are being planted up to considerably north and high elevation in Japan, those species should be examined on their cold resistance in Korea by planting them in further northern part of the country.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.303-313
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• 2020

Rice grain shape is one of the key components of grain yield and market value. An understanding of the genetic basis of the variation in grain shape could be used to improve grain shape. In this study, we developed a total of 265 F₂ individuals derived from a cross between japonica cultivars (Josaeng-jado and Langi) and used this population for quantitative trait locus (QLT) analysis. Correlation analysis was performed to identify relationships between grain traits (GL: grain length, GW: grain width, L/W: ratio of length to width, TGW: 1,000 grain weight). The grain shape was positively correlated with GL and TGW, and negatively correlated with GW. In QTL analysis associated with grain shape, one QTL for GL, qGL5, detected on chromosome 5, explained 20.3% of the phenotypic variation (PV), while two QTLs, qGW5 (PV=36.1) and qGW7 (PV=26.1), for GW were identified on chromosomes 5 and 7, respectively. Evaluation of the effects of each of the QTLs on the grain shape in the population showed a significant difference in the grain size in positive lines compared with the lines without the QTLs. According to the QTL combination of the allelic-types, the grain shape of the tested lines varied from semi-round type to long spindle-shaped type. The results of this study extend our knowledge about the genetic pool governing the diversity of grain shape in japonica cultivars and could be used to improve the grain shape of this species through marker-assisted selective breeding in Korea.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.63-67
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• 2015

Purpose Among various causes that influence image quality degradation, various methods for decrease in Artifact occurred by respiration of patients are being used. Among them, this study intended to evaluate CTAC Shift correction method and additional scan compare to the Scan(Q static scan) using respiratory gated system. Materials and Methods This study was conducted on 10 patients, and used PET-CT Discovery 710 (GE Healthcare, MI, USA) and Varian's RPM system. 5.18 Mbq per kg of $^{18}F$-FDG was injected on patients, asked them to take a rest for 1 hour in the bed, and conducted test after urination. Images were visualized through Q static scan, CTAC Shift correction method, Additional scan based on the Whole body scan(WBS) with Artifact. Decrease in Artifact was compared in each image, conducted Gross Evalution, and measured changes of SUVmax. Results For image obtained through the CTAC Shift correction method through WBS with Artifact, 12~56%, Q static scan image showed 17~54% of change rate and Additional Scan showed -27~46% of change rate. In Blind Test, the CTAC Shift correction image showed the highest point with 4 points, Q static scan image showed 3.5 points, and Additional scan image showed 3.4 points. The standardized WBS scan through Oneway ANOVA and three types of Scan method showed significant difference(p<0.05), and did not show significant difference between the three Scan methods(p>0.05). However, the three Scan methods showed significant difference in Blind test. Conclusion Additional scan and Q static scan require more time than the CTAC Shift correction method, there is concern about excessive exposure to patients by CT rescan and Q static scan is difficult to apply on patients with inconsistent respiration or irregular respiration cycle due to pain. For CTAC Shift correction method, limited correction is possible and the range is limited as well. It is considered as a useful method of improving diagnostic value when hospitals use the system appropriately and develop various advantageous factors of each method.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.26-35
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• 2013

This study was conducted to select superior provenances of Scots pine (Pinus sylvestris L.) well adapted to Korean environment for timber production. In 1976, twenty-two provenances of Scots pine were introduced from Sweden and the seeds were sown in seed beds in March. After one year, the seedlings were transplanted to nursery beds. The resulting 1-1 seedlings of 22 provenances were planted at Whaseong in 1978. Randomized complete block design with 3 replications were used for test plantation. Each provenance was planted with 20-tree row plot in each block and at a spacing of $1.8{\times}1.8m$. The growth performance of each provenance was monitored up to 33-years after planting. There were significant differences among provenances in volume growth. F3001 provenance showed the best volume growth of 33-years after planting ($0.160m^3$), which was 2.2 times greater than that of the lowest provenance W2027 ($0.072m^3$). The ranking of provenances was stabilized after 14 years. Comparing to reference tree species, Japanese red pine (Pinus densiflora), all Scots pine provenances showed poor growth performance. In other words, volume growth of Japanese red pine at age 28 and 33 were 2.1 and 3.3 times greater than that of Scots pine, respectively. Moreover, survival rate of Scots pine was lower than that of Japanese red pine. Based on these results, it was suggested that Scots pine was not suitable to Korean environments. The cause of maladaptation of Scots pine and the implications of introduction breeding were discussed.