• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.6
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• pp.72-85
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• 2002

This study was conducted to investigate the germination rates and ground coverage rates of the 16 native wild flower, herbaceous, shrub and woody plants according to temperature and seeding timing for the revegetation and rehabilitation of the roadside slopes. Also, this study was conducted to suggest design criteria to select revegetation plants and to decide proper seed mixture for ecological restoration of the disturbed manmade slopes as a environmentally friendly construction. The results are summarized as follows. 1. Most of the plants germinated after 10~14 days. Woody plants germinated more slowly than wild flowers and herbaceous plants because of the hard seed. 2. Most of the plants showed the highest percentage of the germination rates under $15/25^{\circ}C$ temperature. The next was in order of under the $20/30^{\circ}C$ temperature, normal temperature(October) and $25/35^{\circ}C$ temperature. 3. At the chamber experiment, the Sorbaria sorbifolia var. stellipila showed the highest germination rates. Most of the native wild flowers germinated well and showed high germination rates under the various temperature. 4. As the field germination experiments, the seeding at August shows higher germination rates than that of the seeding at September, but showed lower surviving percentage of the germinated seedlings and lower ground coverage percentage than those of the seeding at September. After one year, Chionanthus retusus, Acer palmatum, Albizzia julibrissin are germinated and showed 10% coverage rates. So, they can be used as revegetation plants for the restoration works. 5. As seed mixture experiment, it was not effective only to increase the proportion of the ratio of the tree seeds, relatively high price, for making woody vegetation. It would be more successful to make vegetation structure by natural competition among wild flowers, shrubs and trees. 6. The excessive dominance of trees in revegetation works may destroy the lower layer of vegetation and it will be undesirable on the species diversity. It is more important to recover the species diversity of the plant community by seed mixture with the considering the germination, the growth characteristics and the correlation effect among revegetation plants. 7. To recover the manmade slopes quickly, increasing the ratio of the wild flower was recommended.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.7
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• pp.965-973
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• 2011

Our objective was to determine the differences in the rate and extent of dry matter digestion between barley subjected to differing agronomic variables. Two malting barley varieties, Copeland and Metcalfe were seeded at rates of 200 and 400 plants/$m^2$. Each of these varieties received nitrogen fertilizer at rates of 0, 30, 60 and 120 kg/ha, resulting in a total of 20 different barley grain samples. Samples were ground through a 6mm screen and approximately 3 g of each weighed into 50 ${\mu}m$ Dacron bags and sealed. The bags were incubated in three ruminally cannulated Holstein cattle for periods of 0, 3, 6 and 24 h. Using the data obtained from these incubations, rates of digestion were able to be predicted. The soluble fraction ranged from 0.229-0.327, the slowly degradable fraction ranged from 0.461-0.656, and the undegradable fraction ranged from 0.038-0.299. The rates of digestion ranged from 0.127-0.165 $h^{-1}$ and the effective degradability ranged from 0.527-0.757. At the Canora location, the Copeland samples which received 120 kg/ha of nitrogen fertilizer had a significantly lower (p = 0.013) soluble fraction than the rest of the samples at that location. A significant interaction (p = 0.009) was seen between the seeding rate and nitrogen fertilizer application with samples from the Canora location, as well as significant differences (p = 0.029) between nitrogen application rates in samples from the Indian head location. The rate of digestion of samples from the Indian head location differed (p = 0.020) between the two seeding rates, with samples seeded at 200 seed/$m^2$ having a slightly higher rate of degradation. Differences in the effective degradability were seen between the different nitrogen application rates with samples from both the Canora and Indian head locations, as well as an (p = 0.004) interaction between the seeding rate and nitrogen fertilizer application rate. Although there was not a clear correlation between the different variables, both nitrogen application and seeding rate did have a significant effect on the rates and extent of digestion across each of the four locations.

• Journal of Periodontal and Implant Science
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• v.41 no.2
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• pp.73-78
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• 2011

Purpose: For periodontal tissue engineering, it is a primary requisite and a challenge to select the optimum types of cells, properties of scaffold, and growth factor combination to reconstruct a specific tissue in its natural form and with the appropriate function. Owing to fundamental disadvantages associated with using a two-dimensional substrate, several methods of seeding cells into three-dimensional scaffolds have been reported and the authors have asserted its usefulness and effectiveness. In this study, we explore the cell attachment of periodontal ligament fibroblasts on nanohydroxyapatite (n-HA) scaffold using avidin biotin binding system (ABBS). Methods: Human periodontal ligament fibroblasts were isolated from the health tooth extracted for the purpose of orthodontic procedure. HA nanoparticles were prepared and $Ca(NO_3)_2-_4H_2O$ and $(OC_2H_5)_3P$ were selected as precursors of HA sol. The final scaffold was 8 mm in diameter and 3 mm in height disk with porosity value of 81.55%. $1{\times}10^5$ periodontal ligament fibroblasts were applied to each scaffold. The cells were seeded into scaffolds by static, agitating and ABBS seeding method. Results: The number of periodontal ligament fibroblasts attached was greater for ABBS seeding method than for static or agitating method (P<0.05). No meaningful difference has been observed among seeding methods with scanning electron microscopy images. However, increased strength of cell attachment of ABBS could be deduced from the high affinity between avidin and biotin ($Kd=10^{-15}\;M$). Conclusions: The high-affinity ABBS enhances the ability of periodontal ligament fibroblasts to attach to three-dimensionally constructed n-HA scaffold.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.295-303
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• 2006

Clear-cut followed by tree planting has been a conventional management practice in burned forests in Korea. Because this can considerably increase soil loss, hillslope treatments may be needed in order to improve soil stability at poorly regenerating areas. This paper reviews the effects of hillslope treatments, such as seeding, mulching and log erosion barriers, which have been applied to restore vegetation and conserve soil in burned forests in North America and Europe. Seeding has been the most common method for postfire restoration. However, the effects of seeding on vegetation cover and soil erosion are not clear and seeding with non-native species has been reported to inhibit regeneration of native vegetation. Mulching has been found to be effective at reducing soil erosion. However, this also can introduce non-native plant species and inhibit native plant regeration. Although studies on the effect of log erosion barriers are very few, it appears that log erosion barriers are effective in the period of little rainfall. Hillslope treatments for postfire restoration is not necessary for naturally regenerating areas and therefore, they should be restricted to the areas where regeneration potential is low and runoff and soil loss is considerable. Long-term monitoring is needed to assess the effectiveness of hillslope treatments on soil erosion, the introduction of non-native plant species and the inhibition of natural plant regeneration.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.52-56
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• 1981

A 2-year field experiment was conducted to determine the influence of early and late soybean (Clycine max Merr) seeding times on competitive relationships between soybeans and annual weeds. Soybeans were planted on May 20 and June 20. Durations of weed competition and weed control were 0, 3, 6, 9, and 12 weeks after planting sad for full growing season. Dominant weeds were Portulaca oleracia, Centipeda minima, Rorippa cantonienais, Chenopodium album, Acalypha australis, Echinochloa crusgalli, and Digitaria sanguinalis. The dry weight of weeds increased with extended competition, especially at early seeding time of soybeans. Soybean yields were decreased as duration of weed competition was extended. More severe yield reduction occurred at late-planted soybeans with early stage weed competition but at early-planted soybeans when weeds competed with soybeans for a 2 weeds and full growing season. The dry weight of weeds emerged after weeding was decreased at early and late seeding times of soybeans as duration of weed control was prolonged. Soybean yields decreased with shortening duration of weed control end this trend of yield reduction was slightly more remarkable at late-planted soybeans than at early-planted soybeans. Late-planted soybeans were required longer than 6 weeks of weed control period to achieve maximum yield as compared to early-planted soybeans.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.39-45
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• 1995

This experiment was carried out at Yeongnam Crop Experiment Station since 1992 to obtain basic information on ecology of weeds and weedy rice in direct-seeded rice fields. Annual grass weeds of Echinochloa sp., Leptochloa sp., Digitaria sp. and Setaria sp.(C4 plant) and weedy rice(C3 plant) were important species in direct seeded rice compared to transplanted rice field. Period of seedling emergence of barnyard grass was varied from 8 days to 20 days depending on seeding date while it was shorter 4 to 6 days than rice. Weed occurrence and the degree of yield loss were varied by cultivation method. In direct seeding method weeds increased 2 to 3 times compared to manual transplanting. The greatest yield loss was recorded in direct seeding(40 to 100%) followed by mechanical transplanting(25 to 35%) and hand transplanting(10 to 20%), in order. Double cropping of rice-barley was reduced weeds about 30% than rice single crop due to alleopathic effect of barley residue or stubble. Weedy rice(red rice) occurrence was closely related with seeding date and tillage methods. Early seeding and reduced tillage enhanced the growth of weedy rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.4
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• pp.287-298
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• 2019

The aim of the present study was to compare the germination and seedling characteristics of rice varieties grown under various flooding conditions and different temperature and oxygen levels and to identify germplasm suitable for wet direct seeding. Three anaerobic germination tolerant (AGT) genotypes (PBR, WD3, KHO) and eleven Korean rice varieties (KVs) adapted for direct seeding were evaluated for seedling performance under different temperatures (15, 18, 21, and 24℃ ) and oxygen levels (Low, Normal, High). Compared with the KVs, the AGT genotypes (especially KHO and PBR) exhibited relatively high germination and survival rates and coleoptile and radical growth rates under low temperature and low oxygen conditions, thereby indicating their suitability for wet direct seeding. Among the KVs, 'Dongan,' 'Jungan,' and 'Cheongdam' rice exhibited the highest survival rates under low temperature and low oxygen conditions. Three-way ANOVA indicated that temperature had the greater effects on seedling characteristics (43.2-78.0%) than either oxygen level (15.4-37.5%) or genotype (2.0-29.8%) did. Therefore, in direct seeding cultivation, temperature was the most important environmental factor for seedling establishment.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.157-162
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• 1996

Experiments were conducted from 1994 to 1995 to understand the effects of the labor-saving seeding and planting density on growth and root yield of Astragalus membranaceus. The drilling seeder reduced seeding time than the hand seeding; It takes 3. 5hrs/l0a to seed by drilling seeder while 33. 0hrs/l0a by hand seeding, which labor reducing rate was 89. 4 %. Emergence rate in the drilling seeder was increased 17% than in the hand seeding, so the root yield were increased 23% to 136. lkg/l0a in using drilling seeder compared to 110. 3kg in hand seeding. On the effect of planting density on the growth characteristics plant height was long in dense planting and stem diameter was thick in spacious planting. Root diameter and dry root weight root per plant were decreased in dense planting and root yield was highest in optimum planting densities $(6\;row\;(15cm)\;{\times}\;10cm)$ in the harvest of 1 year old plants in Astragalus membranaceus. The gross profit were increased 23% to 1,933 thousand won per l0a in the drilling seeder compared to 1,566 thousand won in the hand seeding, also the managing costs were reduced 18% to 406 thousand won per l0a in the drilling seeder than 494 thousand won per l0a in the hand seeding.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.197-210
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• 2009

To improve the forage quality and reduce nitrogen input, trial was conducted on the effect of seeding method, combination, and nitrogen fertilizer with WCB (whole crop barley) and leguminous plant. Present experiment was carried out by split-split design having seeding methods for main plot, combinations for sub-plot, and nitrogen fertilizers for sub-sub plot with three replications. When WCB and leguminous plant were mixed-sown, WCB showed earlier heading and maturing than those of inter-sown, and the more nitrogen delayed growth stage a little. Occurrence of BaYMV (Barley Yellow Mosaic Virus), a serious disease caused by soil fungi and decrease barley yield, was deterred by mixed-seeding as compared to inter-sown barley a little. Inter-sown WCB increased the number of spike per $m^2$ as compared to mixed-seeding showing more spikes with nitrogen increase. WCB produced much fresh and dry matter yield at mixed-seeding than inter-seeding, and had advantage with hairy vetch (HV). Increased nitrogen showed much forage yield, however, half application of it is considerable for environmental-friendly farming. Electric conductivity (EC) decreased in inter-cropping or mixed-sowing soil with WCB and leguminous crop after harvest. But, organic matter (OM) content of soil after harvesting was vice versa. Acid detergent fiber (ADF) and Neutral detergent fiber (NDF) of WCB plant were higher at mixed-seeding than those of inter-sown ones. It showed increased tendency with time progress.

• Korean Journal of Organic Agriculture
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• v.15 no.1
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• pp.59-69
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• 2007

This experiment was conducted to study the spring productivity and feeding value of hairy vetch varieties. We also measured DM yield and feeding value by analyze CP and CF that authors made possible to calculate TDN and RFV. The results can be summarized as follows; Dry matter yield were increased earlier autumn seeding date and later cut in spring. Differences of dry matter yield in earlier cut in spring was high in order of Ostsaat, Welta, Vv4712, Penn-02, Common and Minnie. Crude protein(CP) yield was increased when earlier autumn seeding date and later cut in spring. Total digestible nutrient(TDN) yield of hairy vetch varieties was decreased when later autumn seeding date, and was increased when later cut in spring. TDN yield was highest in Ostsaat and Welta varieties had highest dry matter yield. Acid detergent fiber(ADF) content was decreased when later autumn seeding date and was increased when later cut in spring. Neutral detergent fiber(NDF) content was decreased when later autumn seeding date. Average values for relative feed value(RFV) were 157% and 132% in both cut. It shows that a high feed value in all of hairy vetch varieties. Above all, the results presented that the optimal seeding date for cultivating hairy vetch in the central region of Korea is between the 10th to the 20th of September. Because Ostsaat and Welta had significantly high dry matter yield we expected Ostsaat and Welta have a higher wintering ability.