• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.1
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• pp.129-136
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• 2010

This study was initiated to investigate thatch accumulation in several turfgrasses grown under two soil systems. The 45 centimeter deep USGA system was constructed with rootzone, intermediate and drainage layers. The mono-layer system, however, was made with only a 30cm rootzone layer. Turfgrasses used in the study were comprised of 3 varieties from Korean lawngrass of Warm-Season Grass(WSG) and 3 blends and 3 mixtures from Cool-Season Grass(CSG). A total of 9 turfgrass treatments were replicated three times in RCBD in both systems. Cultural practices for the research plot followed a typical maintenance program for highly managed turf. Treatment differences for thatch accumulation were observed among the turfgrasses in both soil systems. Thatch under the USGA system was 9% greater than under the mono-layer system due to its more favorable conditions for turf growth. Higher thatch depth was found with Korean lawngrass, 34~87% in the USGA system and 16~75% in the mono-layer system when compared with CSG. Among WSG, the Joongji variety was the highest in thatch layer under both the USGA and mono-layer systems. Kentucky bluegrass(KB) was the greatest among CSG, since it is a rhizomatous-type in growth habit, resulting in faster production of organic matter over bunch-type of tall fescue and perennial ryegrass. Proper depth in the thatch layer was known to be beneficial by enhancing the resiliency and wear tolerance of the turf in athletic fields. Thus, KB was considered to be a very excellent turfgrass in terms of turf quality, environmental performance, physical properties and soccer player safety. However, disadvantages such as poor water-holding properties, more inclined to injury from environmental stresses and severe diseases and insect injury were also expected where thatch was excessively accumulated. Therefore, these results demonstrate that more frequent measures for controlling thatch such as vertical mowing, topdressing or coring should be employed for soccer fields with Korean lawngrass and KB over other turfgrasses.

• Korean Journal of Environment and Ecology
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• v.28 no.6
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• pp.657-663
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• 2014

This study was conducted to investigate the difference in feeding habits of Red-Tongued Viper Snakes, according to available foods sources and areas. The effects of differences in food sources were found on Red-Tongued Viper Snake inhabited in the Jeju Island and its islet Gapado, from May 2006 to Nov. 2010. The food sources for the Red-Tongued viper snake population in the Jeju Island were found to be as follows: Chinese red-headed centipedes (Scolopendra subspinipes mutilans), Jeju Salamanders (Hynobius quelpaertensis), Japanese tree Frogs (Hyla japonica), Narrow-mouthed Toad (Kaloula borealis), Dybowski's Brown Frogs (Rana dybowskii), Black-spotted Pond Frogs (Rana nigromaculata), Smooth Skinks (Scincella vandenburghi), Asian Keelback Snakes (Amphiesma vibakari), Lesser White-toothed Shrews (Crosidura shantungensis), Hallasan Shrews (Sorex caecutiens hallamontanus), and Jeju Striped Field Mice (Apodemus chejuensis). This implies that Red-Tongued Viper Snakes mainly feed on amphibians, reptiles, and small mammals. Among these, amphibians occupied the highest portion at 55.2% followed by mammals at 20.7%, centipedes at 13.8%, and reptiles at 10.3%. On the contrary, Red-tongued viper snake population in Gapado only feed on Chinese red-headed centipedes and Smooth Skinks (S. vandenburghi). Since only a small amount of nutrient can be obtained from Chinese red-headed centipeds or Smooth Skinks, this feeding habit for Red-tongued viper snake would adversely effect on the growth or regeneration. The reason why Red-Tongued viper snake population in the Gapado mainly feed on Lizard and Centipedes in spite of relatively various available food sources, might be due to the low density of other food sources in the Gapado. Red-Tongued viper snake could be feeding on foods that are low in quality but are easily accessible, to minimize energy consumption on searching for other more nutritious foods. A snake tends to select the size of its food depending on the size of its own head. The positive correlation was found between the size of the heads of Red-Tongued viper snakes from the Jeju island and the diameter of their foods. The head size was larger in the males than females in viper snake population from the Jeju Island, which might effect on their selection of foods. However, no significant difference was found between the sizes of the head and the food in the Red-Tongued viper snake population from the Gapado. The findings of this study would provide meaningful data, which directly shows that even within the same viper species they choose different available food sources according to their inhabitance. This leads to their growth and adaptation to their environment which is beneficial for sustaining of its population.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.3
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• pp.124-139
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• 2016

This study was carried out to characterize 127 recently developed cultivars of Rose of Sharon (Hibiscus spp.) in Korea and foreign Countries for landscape uses. The examined factors were growth characteristics such as tree height of a 1-year grafted plant(cm), plant type, growth habit, leaf characteristics such as shape and size, flower characteristics such as color, shape, size, and red eye during 2014 and 2015 for landscape uses. The results are obtained as follows; In the results of flower color of the 127 recently developed cultivars, pink color with red eye spot, white color with red eye spot, purplish red color with red eye spot, violet purple color with red eye spot, crimson color with red eye spot, asadal, blue color with red eye spot, and white color were distributed. In the flower characteristics, Hibiscus hybrid 'Daewangchun' had the largest flower size of 16.0cm out of the 127 cultivars. H. syriacus 'Antong', 'Lil Kim', and 'Ggoma' were cultivars with smaller flowers than other cultivars. H. syriacus 'Hunjang' had largest red eye, of 5.2cm of length compared to the other cultivars. The cultivars with unique flower color for landscape uses are H. syriacus 'Kwangmyung', 'Nanpa', 'North face', 'Bulsae', 'Bidan', 'Songam', 'Youngchang', 'Jukpeoso', 'Kiho', 'Tamla', 'Hwasoored' and 'Hwanhee'. These flowers had a purplish red color and were developed in Korea. H. syriacus 'Aphrodite', 'Dr. Uemoto', 'Freedom', 'Pink Cup', 'PS 80-1', 'Purpureus Variegatus', 'Red Giant', 'Woodbridge' also had unique flowers with a purplish red color and were introduced from foreign countries. In addition, cultivars with violet pink flowers were H. syriacus 'Ggoma', 'Doturak', 'Myungmi', 'Byunghwa', 'Sancheonyu', 'Taehwa', 'Hikari-hanagasa', and 'Little Kim Violet'. 'Jongmoo' and 'Ruffled Satin' had flowers with crimson color. Therefore, the new cultivars with unique flower colors were a promising cultivars to a woody landscape plant. Cultivars with large flower sizes were Hibiscus hybrid 'Daewangchun', Hibiscus hybrid 'Daemang', and Hibiscus hybrid 'Jina'. H. syriacus 'Ggoma', 'Mibeak', 'Antong', 'Lil Kim', and 'Eunhasu' had small flower sizes. Cultivars with long red eye were H. syriacus 'Hunjang' and H. syriacus 'Hi Lea Red'. Therefore, the new cultivars, Hibiscus hybrid 'Daewangchun', Hibiscus hybrid 'Daemang', Hibiscus hybrid 'Jina' with large flower sizes, H. syriacus 'Ggoma', 'Mibeak', 'Antong', 'Lil Kim', and 'Eunhasu' with small flower sizes, H. syriacus 'Hunjang' and H. syriacus 'Hi Lea Red' with long red eye, were promising cultivars to a woody landscape plant.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.298-303
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• 1981

A study was conducted to find out the varietal difference in some important agronomic characters in response to different seeding time in barely from 1975 to 1976 at Chikugo Agric. Expt. Station in Japan. Thirteen varieties which are diverse in growth period were used. Nine seeding time were tried. Seedling emergence, primary tillering, and formation of flower primodia were delayed in proportion to the seeding time. And also heading and maturing time showed the same tendency. This tendency appeared more conspicuous in the late maturing varieties. Therefore, days to heading and maturing duration were inversely shortened by the delay of seeding time and by earliness of variety. Number of spikes as well as culm length and spike length was reduced in the late seeding. Grain yield was reduced in all varieties by late seeding, easpecially with late maturing varieties. In this test, widely adaptable variety to late seeding time was not found, but earliness and high tillering in growth habit appeared more favorable to yield increase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1634-1640
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• 2004

This study was designed to compare the nutritional intake and iron nutritional status between urban and rural middle school girls. Along with a questionnaire, blood samples were obtained from 311 middle school girls (urban 129 girls, rural 182 girls). Nutrient intakes were measured with a convenient method, and clinical symptoms relating anemia was investigated by 4-point Likert scale. For the nutrient intake, the total energy intake was 1722.2 kcal (82.0% of RDA) for the urban group and 1649.5 kcal (78.6% of RDA) for rural group. The rural group showed significantly lower level than the urban group in all nutrients except fat, carbohydrate and total energy intake. Regarding the food frequency, students from the rural group marked significantly lower intake of milk (p<0.00l), kimchi (p<0.05), fruit (p<0.05), tofu, bean (p<0.00l) than the urban group. For every clinical finding regarding anemia, the rural group marked higher value than the urban group but the difference was not significant. The hemoglobin concentration of urban group was 13.28 g/dL, and rural group showed 12.51 g/dL which was significantly lower than urban group (p<0.00l). The hematocrit rate was 37.82% for the urban group and 38.13% for the rural group and there was no significant difference between two groups. The red blood cell (RBC) count of the rural group was significantly lower than the urban group (p<0.00l). Evaluating with the iron deficiency standard which is less than 12 g/dL, the urban group was 6.2% and the rural group was 34.6% thus the deficiency rate was significantly higher in the rural group. This study showed that nutrient and iron status of the girls of rural group is not as good as the urban group. As middle school girls require high level of iron absorption due to blood loss which occurs during abrupt physical growth and menstruation, dietary counselling is required to enhance the iron status. When iron deficiency is serious, they need to take more positive action such as iron supplement in addition to food-iron fortification.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.2
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• pp.123-133
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• 1992

This study was conducted to clarify progressed changes of plant types and the effects of the physiological and ecological components on improving ideotype of winter wheat. 12 wheat varieties were planted at the experimental farm of Wheat and Barley Research Institute in Suwon in 1990. As results of intensive wheat breeding for early maturity since 1959, heading, flowering and maturing dates have been shortened by 17, 15 and 14 dagys, respectively. The shortened days from sowing to heading and from heading to flowering contributed to the early maturity to improved. Physiological factors associated with heading time of wheat could be reprsented by growth habit, photoperiod responses, earliness in narrow sense and winter hardiness. For improving an early maturity of winter wheat, it would desired to maintain some degree of winter habit(III-IV), and recombination of more insensitivity to short day length and more shortened earliness in narrow sense than that of Saemil and Chugoku 81, and higher degree of winter hardiness. For improving the early maturity the more effective way must be of shortened days from sowing to heading, and days from flowering to maturity than days from heading to flowering. Ideotype of wheat will be desired to recombine two semi-dwarf genes with erect plant type being about 70-80cm, less stem elongation by late spring, long spike and many grains per spikelet. Average spike weight ratio was about 45-49% in high-yielding varieties, stem fresh weight was lighter, but spike fresh weight was heavier in new one while leaf fresh weight was similar to each other during the maturing periods. Average spike dry weight ratio was higher about 40～48%, and stem and leaf blade dry weights were lower in the newly bred varieties. Stem dry weight was heavier than spike or leaf dry weight in the old varieties of Yungkwang, Jangwang and Jinkwang. Leaf area index for the varieties showed normal distribution curve as the maximum point in booting stage. The maximum point of this curve come in early maturing wheat, and late in old one. The maximum points of LAI were 6.4～6.8 in the high-yielding varieties. Totals of LAI in each period investigated of old one were higher than those of newly bred being 24.6～28.8. Chlorophyll content of the high-yielding varieties of Chokwang, Geurumil and Saemil as higher than that of the old varieties Jangkwang, Jinkwang, Wonkwang and Sinkwang from regrowing period to April 21. after then slightly and even after heading. Net assimilation rate (NAR) was higher in high-yielding varieties with good plant type, and lower in old ones. Grain yield of the newly released varieties increased rapidly but slowly in the old ones. Change in water content of grain at the growing stage in newly bred was lower than that of the old bred. Diminishing rate of water content of grain in establishment per day was 1.2% average that of the old varieties including Yungkwang was 1.5%, and those of the newly bred including Chokwang were 0.9～1.1%. Chokwang, Naemil, and Saemil were the highest-yielding varieties of the Korean cultivars. Yields were increased by spikes per m$^2$, grain weight for the varieties bred in Suwon, and by spikes per m$^2$ for the varieties bred in Milyang.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.655-661
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• 2016

To develop scab-resistant pear (Pyrus spp.) varieties with fruits that are as crisp and juicy as Asian pears, a cross was made between 'Whangkeumbae' and 'Bartlett' varieties (P. pyrifolia ${\times}$ P. communis) at the Pear Research Institute of the National Institute of Horticultural & Herbal Science, Rural Development Administration, in 1994. Among the 285 seedlings, 'Greensis' was first selected in 2006 for its good eating quality and named in 2012 after regional adaptation tests in nine regions and ten experimental plots from 2007 to 2012. The tree showed a vigorous growth habit and semi-spreading characteristics, like 'Whangkeumbae'. The optimum fruit harvest date was also around Sept. 26 and fruit was round in shape and green in skin color at maturity. Average fruit weight was 470g, and the soluble solids content was $12.4^{\circ}Brix$. The flesh was very crisp and juicy, and had good eating quality. Its' leaf size was similar with 'Bartlett' and smaller than 'Whangkeumbae'. The average of full bloom date of 'Greensis' was determined as Apr. 26, which was six days later than 'Whangkeumbae' and similar with 'Bartlett'. S genotypes of 'Greensis' were identified as $S_4S_e$ by S-allele PCR product sequencing analysis. It seems that the $S_4$ allele was inherited from 'Whangkeumbae' and the Se allele from 'Bartlett'. 'Greensis' displayed strong resistance to scab disease caused by Venturia nashicola, similar to European pear cultivars like 'Beurre Hardy' and, 'Conference'. 'Greensis' was also highly resistant to black leaf spot (Alternaria kikuchiana) in the field

• Horticultural Science & Technology
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• v.29 no.6
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• pp.645-650
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• 2011

Pear cultivar 'Supergold' (Pyrus pyrifolia var. culta Nakai) was originated from the cross between 'Chuwhangbae' and 'Manpungbae' with the aims of improving the fruit quality of 'Chuwhangbae' cultivar at Pear Research Station of National Institute of Horticultural & Herbal Science, Rural Development Administration in 1994. 'Supergold' was preliminarily selected in 2002 and named in 2008. The tree shows a vigorous growth habit and semi-spread characters like as 'Manpungbae'. Furthermore, it has sufficient flowers and carries abundant pollen grains, so it can also be used as a pollinator. 'Supergold' is highly resistant to black leaf spot (Alternaria kikuchiana) in the field condition. The optimum harvest time is around Sep. 11th, which is ahead of 'Whangkeumbae' about 5 days in the harvest period. The fruit shape is oblate and fruit skin color is greenish-white at harvesting time. The average weight of fruit is 570 g, and the soluble solids content is $13.6\;^{\circ}Brix$. The flesh is very soft and juicy, and renders good eating quality. Shelf life is about 6 months under the cold storage condition. To determine the self-incompatibility (SI) genotype of 'Supergold' pear cultivar, it was crossed with other cultivars of which SI genotypes have already known. The result of cross-pollinations of 'Supergold' with other cultivars showed relatively high rates of fruit set from 64.5% to 91.0%, except for the cross with pollens of 'Nijisseiki' that represented only 28.8% of fruiting rate. Although sometimes the stigma of 'Supergold' crossed with 'Hayatama', 'Chojuro', and 'Nijisseiki' showed malformed pollen tube tips, 'Supergold' is generally supposed to have cross-compatibility with all other pollen donor cultivars. It is considered that the S-allele of 'Supergold' is $S_3S_4$, which is based on the result of PCR-RFLP.

• Journal of Korean Home Economics Education Association
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• v.17 no.2
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• pp.79-93
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• 2005

The purpose of this was to present the efficient directions of nutrition education for elementary school children. We examined the problems of eating habits. nutrition knowledge, and perception and expectations on nutrition education of elementary school children in school. This study was carried out using a self-administered questionnaire and subjects were 562 elementary school children in Gyeonggi Province. All data in this research was analyzed through SAS program, and the frequency$(\%)$ and the $mean{\pm}S.D.$ on each question were calculated. Data for each group was analyzed according to sex and the difference among the groups were treated for significance by using chi-square test and Student t-test. About $87.6\%$ of the children have a meal over three times a day, and $76.7\%$ answered that they ate at a certain time regularly everyday. Only $69.6\%$ of subjects said that they ate breakfast everyday, showing very high levels of skipping breakfast. The most common frequency of eating snacks was 'once a day' in both sexes(male $52.2\%$, female $48.6\%$). In the perception on the eating habits, $69.3\%$ of children recognized problems on dieting habits, such as unbalanced diet. irregular eating time, and overeating. The perceived and correct knowledge of nutrition were $99.5\%$ and $86.9\%$, respectively. Most of the children$(99.1\%)$ acknowledged that nutrition education need to be carried out in school. And children want to deeply deal with 'cooking', 'growth and nutrition', 'good eating habits', 'nutrition and disease', These results indicated that elementary school children tended to have undesirable eating behaviors, but the rate of children who recognize the importance and the needs of nutrition education in school was high. Therefore, their parents and teachers need to perform continuous education through a curriculum and life instruction so that students have healthy habits by considering what the problems of nutrition habits are, as the elementary students considerably recognize problems of their own dietary habits and needs of nutrition education.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.57-62
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• 2015

"Nokyang" (Hordeum vulgare L.), a new whole-crop silage barley cultivar, was developed by the breeding team at the Department of Rice and Winter Cereal Crop, National Institute of Crop Science, RDA, Korea in 2012. It was derived from combining "Nagyoung" and breeding line "SB77368-B-145". Among the combinations made in 2001, a promising line, "SB01T2017", showed good characteristics in terms of potential forage yield in the yield trial at Iksan from 2007 to 2009. In 2009, the promising line was designated as "Iksan457" and placed in regional yield trials at six locations around Korea for three years from 2010 to 2012, and was released under the name of "Nokyang." It has the growth habit of a group III creeping plant type, with a light-green leaf and common spike. Its average heading and maturing dates were on May 6 and June 4, respectively, which were later than cultivar "Youngyang." "Nokyang" also showed strong winter hardiness, and a resistance to shattering and barley yellow mosaic virus (BaYMV) similar to those of the check cultivar. The best thing among the traits of one is a new good quality with the plant green at the latter growing period. The average forage dry matter (DM) yields in the regional yield trial were about 12.8 and 11.5 MT $ha^{-1}$ in upland and paddy field, respectively, which were higher than those of the check cultivar, by 7% and 2%, respectively. This cultivar would be suitable for an area of the Korean peninsula where the daily minimum temperature in January is above $-8^{\circ}C$.