• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.46-54
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• 1993

On the purpose to increase the cultivation stability of the hulless waxy barley which is unstable in the northern region of Korea, the effects of genes of hulled /hulless and waxy /nonwaxy on seedling emergency was studied by using four isogenic lines of hulled -waxy, hulless -waxy, hulled -nonwaxy and hulless -nonwaxy barley. The germination rates of hulless lines lowered by four to six percent compared with those of hulled counterparts with one day's rainfall just before harvest, and were much deteriorated with raining prolonged. The gaps between emergency rates of hulless lines and their counterparts were greater than those of germination rates, and the differences increased as the seeding depths were deepened. The emergency rates of hulless lines were affected in the order of seeding depth, rotation speed of thresher and preharvest rainfall. Waxy endosperm gene did not show any significant effects on the damage of grain during threshing. It seems that the embryos of hulled lines were less damaged than those of hulless ones during threshing due to the protecting effects by husks. When grains were threshed with thresher of 600rpm or 900rpm and dehulled with dehuller of 750rpm, any significant depreciations such as broken seeds and decreased germination rate did not occured in hulled lines. But the grains of hulless lines received some damages with the rotation speeds, especially germination rates decreased seriously when the rotation speed of de huller was high. Prehavest sprout rates of the lines incorporated with the waxy genes were higher than those with nonwaxy genes whereas the genes of hulled and hulless did not give any significant effects.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.2
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• pp.101-108
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• 2007

The object of this experiment was to investigate the effect of mixture which consist of different seeding rates and species on dry matter yield and quality in Daejon area. The field trials were conducted from 2003 to 2005 at Chungnam National University in order to evaluate the dry matter yield and quality of different mixture. The experimental design includes three mixture types: Conventional mixtures, CM{orchardgrass(Potomac) 50% + tall fescue (Fawn)20% + Kentucky bluegrass(Kenblue) 20% + white clover(Regal) 10%}, red clover + mixtures, RM{orchardgrass(Potomac) 40% + tall fescue(Fawn) 20% + Kentucky bluegrass(Kenblue) 10% + red clover(Kenland) 30%) and Turf type grass + mixtures, TM {orchardgrass (Potomac) 50% + turf type grass (tall fescue, Millennium 20% + Kentucky bluegrass, Midnight 10% + perennial ryegrass, Palmer III 10%) + white clover(Regal) 10%}. The average DM yield for 2 years of red clover+mixture(11,656kg/ha) was higher than those of the other mixtures(p<0.05). The content of crude protein and dry manu digestibility were higher in red clover+mixture than in other mixtures(p<0.05). but, the content of fibrous compounds like as NDF, ADF, cellulose and lignin were lower in red clover+mixture than in other mixtures(p<0.05). The crude protein dry matter(CPDM) yield was higher in red clover + mixture(2,832kg/ha) than in conventional mixture(2,372kg/ha) and turf type + mixture(2,266kg/ha)(p<0.05). The digestible dry matter (DDM) yield was higher in red clover + mixture(8,881 kg/ha) than in conventional mixture(8,255kg/ha) and turf type + mixture(7,314kg/ha)(p<0.05). In botanical composition at last cutting time in 2005, conventional mixture were maintained orchardgrass 45%, tall fescue 22%, Kentucky bluegrass 5% and white clover 24%. Red clover + mixture were maintained orchardgrass 40%, tall fescue 22%, Kentucky bluegrass 4% and red clover 31%. turf type + mixture were orchardgrass 37%, tall fescue 23%, Kentucky bluegrass 6%, perennial ryegrass 8% and white clover 24%, respectively. As summary, DM yields and quality of mixture species and seeding rates were observed significant difference. The results of this experiment indicated that red clover + mixture was more effective in enhancing the DM yield and forage quality in Daejon area.

• Journal of Gastric Cancer
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• v.14 no.2
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• pp.123-128
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• 2014

Purpose: Since there are no proven tumor markers that reflect the course of gastric cancer, carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) are commonly used alternatives. However, the degree of progression that corresponds to an increase in these markers, and the values of these markers at different cancer stages, remains unclear. Materials and Methods: This study enrolled 1,733 gastric cancer patients who underwent surgery and whose pre-operative CEA and CA19-9 levels were known. Survival curves and mean values of the two markers were compared according to the degree of cancer progression: serosa-unexposed (SU), serosa-exposed (SE), direct invasion (DI), localized seeding (P1), and extensive seeding (P2). Results: The 5-year overall survival rates at each stage differed significantly, except between DI and P1 patients (17.1% vs. 10.5%, P=0.344). The mean CEA values in SU, SE, DI, P1, and P2 patients were 5.80, 5.48, 13.36, 8.06, and 22.82, respectively. The CA19-9 values for these patients were 49.40, 38.97, 101.67, 73.77, and 98.57, respectively. The increase in CEA in P2 patients was statistically significant (P=0.002), and the increases in CA19-9 in DI and P2 patients were significant (P=0.025, 0.007, respectively). There was a fair correlation between the two markers in P2 patients (r=0.494, P<0.001). Conclusions: CA19-9 can be used to assess DI of gastric cancer into adjacent organs. Both markers are useful for predicting the presence of extensive peritoneal seeding.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.4
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• pp.309-313
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• 1997

Field experiments were conducted on Jeonbug series (Fine silty, mesic family of Aeric Fluventic Haplaquepts), to study the effect of split application of N fertilizer in combination with rice straw on N use efficiency of dry-soil-direct seeded paddy rice. Treatments involved conventional application of N (in three splits; 40% at planting, 30% at five leaf stage and at heading stage) without rice straw, all basal application of N with straw application (5000 kg/ha), N application in two splits (70% at planting and 30% at heading stage) with rice straw application and N application in three splits (40% at planting, 30% at five leaf stage, 30% at heading stage) with application of rice straw. There was Zero N plot too for the estimation of N use efficiency. Seeding was done on dry soil and the filed was flooded 32 days after seeding. The fertilizer application rates were 160, 70, and 80 kg/ha of N, $P_2O_5$ and $K_2O$, respectively. The experiment was conducted for two years, in the same filed. The apparent use efficiency of fertilizer N by rice tended to be higher under the application of rice straw when N was applied in three splits. This, however, did not increase the yield of rice significantly. Even under the application of rice straw, the apparent N use efficiency was lower when N fertilizer was applied in one dose at the planting and in two splits. The lower N use efficiency in these cases, did not yield of rice significantly. The periodical analysis of mineral N in the soil suggested that higher mineral N in the soil at the early stages was responsible for the lower apparent N use efficiency.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.9-15
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• 2017

Germination characteristics, seedling emergence, and early seedling growth of iron-coated rice seeds, cultivars Daebo and Samdeokbyeo, under different water depths were compared with those of non-coated seeds (control) and the results evaluated to obtain basic information for establishing stable seedlings in direct water seeding. The total germination percentage of the two seed treatments was similar, but iron-coated seeds had slightly faster germination and shorter mean germination time than non-coated seeds. Water absorption rates of iron-coated seeds were lower than that of non-coated seeds during seed germination. The germination percentage of the two iron-coated rice seed cultivars showed a significant decline of 15-22% after one year of storage under natural conditions. The seedling emergence percentage and uniformity of the two rice cultivars were significantly higher in the iron-coated seeds at 1-13 cm water depths but the percentage of floating seedlings was lower in iron-coated seeds than in non-coated seeds. The iron-coated seeds had a high seedling emergence percentage of 91.3-93.3% at all flooding depths whereas the non-coated seeds had a significantly low seedling emergence percentage of 57.7-71.7% at a water depth of 13 cm. Moreover, the shoot dry weight and seedling health score of iron-coated seeds were significantly higher than those of non-coated seeds, while root dry weights were similar in iron-coated and non-coated seeds, regardless of water depth. These results suggest that iron-coated seeds are more appropriate for stable seedling establishment in direct water seeding than are non-coated seeds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.3
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• pp.327-331
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• 2009

Korean government has promoted the policy of chemical fertilizer reduction by 40% reduction from 2003 to 2013. Hairy vetch (Vicia villosa Roth) fixes nitrogen from the atmosphere and rye (Secale cerale L.) accumulates soil nitrogen to reduce potential nitrogen loss. The objective of this research was to identify optimum seeding rates of hairy vetch-rye mixtures in the central regions of Korea. The experiment of mixture rate was carried out for maximum production in 2006 and 2007. The best seeding rate mixture for maximum biomass production was 6.75 kg hairy vetch and 5 kg rye per 10a. Pure hairy vetch and rye were used as control. The nitrogen production of mixture treatments were higher than pure rye. The hairy vetch and rye mixture can scavenge potentially leachable nitrogen, while maintaining soil fertility by adding fixed nitrogen to the cropping system.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.106-115
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• 1998

This study was conducted to investigate the effect of oxadiazon, molinate, thiobencarb before seeding on control of red rice and barnyardgrass in water-seeded rice. High application rate plot among oxadiazon treatment plots could observe phytotoxicity symptoms depending on field conditions, but these injury recovered gradually with time. Molinate and thiobencarb application plots at the concentration of 225~400, 210~420g ai/l0a respectively were not observed phytotoxicity. Control of red rice was different according to kinds of herbicides and application rates. Oxadiazon showed higher control performance at the concentration of more than 60g ai/10a. Control effect of molinate and thiobencarb against red rice was enhanced with the increase of application rate, and both herbicides showed satisfactory effect at more than 300g ai/10a. Control of barnyardgrass showed up to 90~100% in all tested herbicides. There was no significant yield reduction by oxadiazon, molinate, and thiobencarb application before seeding in all tested field. In the pot experiment, crop injury, seedling stand, and early growth were more advantageous at time of drainge after one day after seeding than flooding until rooting.

• Journal of Biosystems Engineering
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• v.43 no.4
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• pp.303-310
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• 2018

Purpose: This research was conducted to determine the design factors of a seed-metering device for the development of a seeder. The device allows the seeder to sow precisely one to three seeds of foxtail millet and sorghum. To obtain fundamental information regarding the design of the seed-metering device, examination of the physical properties of foxtail millet and sorghum was conducted. Methods: Based on the results of an adaptability test using an existing seeder with foxtail millet and sorghum, an experimental roller-type seed-metering device was made. The seeding factors considered during the experiment were the width, length, and depth, as well as the shape of the groove in the seed-metering roller. By adapting an analysis of variance, the experimental results of the seeding factors were analyzed. Results: The measured results of the respective lengths and widths of the seeds were 2.11 and 1.64 mm for foxtail millet, and 3.68 and 3.32 mm for sorghum, respectively. The weight of 1,000 seeds was 2.43 g for foxtail millet and 17.5 g for sorghum. The seeds were of an elliptical shape, considering the length and width. A sieve analysis showed that the size distribution of foxtail millet was quite regular whereas that of sorghum was irregular. Conclusions: The seeding results showed that the rates of incorrect planting were low when the groove of the roller-type metering device is an elliptical type. To sow one to three seeds, the groove of roller-type metering devices $2.0mm{\times}4.0mm{\times}1.5mm$ ($width{\times}length{\times}depth$) for foxtail millet, and $4.0mm{\times}8.0mm{\times}3.0mm$ and $4.5mm{\times}8.0mm{\times}3.0mm$ ($width{\times}length{\times}depth$) for Sorghum.

• Korean Journal of Organic Agriculture
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• v.26 no.4
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• pp.719-729
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• 2018

Green manure crops can be efficient replacements of high nutrient materials such as livestock compost, organic fertilizers, etc. in organic farming. Grass-legume mixtures or mixed cropping of legumes with non-legumes can aid in abating the shortcomings of each plant type under monoculture (i.e. legumes have low biomass yields while grasses are poor at fixing nitrogen). This study was conducted to investigate the effects of barley (B) and hairy vetch (H) mixtures on green manure yield in nutrient accumulated organic upland soils of Korea. In one cropping season, single crops of barley and hairy vetch (Barley: 160 kg/ha, Hairy vetch: 90 kg/ha) as well as mixtures of both crops at different seeding rates (B66:H33, B33: H66) were grown and the obtained results are as shown below. The biomass yield and nutrient productivities were higher in barley-hairy vetch mixture. The biomass yield and total phosphorus content were higher for the mixed crops by 78~132% and 200% respectively than those of the hairy vetch monoculture. Total nitrogen content of the mixed crops was also higher than those of the barley monoculture by 43~44%. The biomass yield (5.60 Mg/ha) and nutrient contents (87.7 kg N/ha, 23 kg $P_2O_5/ha$) were highest in the case of B66:H33 seeding rate. Accordingly, this study concludes that the barley-hairy vetch mixtures cropped at B66:H33 seeding rate is efficient in increasing green manure productivity due to complementary effects observed and the highest biomass yield and nutrient contents.

• Korean Journal of Medicinal Crop Science
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• v.2 no.2
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• pp.114-120
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• 1994

Experiment was conducted to investigate the effects of planting date and planting methods with seedling size on bolting and yield of Ostericum koreanum (MAX.) KITAGAWA Seeding methods were also reviewed to imvestigate their effects on seedling characteristics. This experiment was carried out in Chuncheon during 1988 growing season. The small seeding rate and broadcasting had higher rates of emergence than the others. There was no big difference in seedling size by seedling rate, and more seedling growth was in drilling methods among seed planting methods. The quantity of seedling were produced with the order of medium, small and lastly large seedling. Dense planting $(8l\;/33m^2)$ was advantageous in producing small seedling. Large seedling had earlier flowering than the others and growth was good in planting small seedling with drilling method. The rates of bolting by seedling sizes were 89.6% in large, 64.6% in medium and 36.9% in small seedling. Bolting was influenced the root Quality by producing lignified root which had a least commercial value. More root growth was shown in unbolting plant compared to bolting plant seedling and broadcasting had much more root growth than seedling from drilling. Fresh root yield of unbolting plant was higher than that of bolting plant and highest yield was obtained in the broadcasting plot with small seedling.