• Journal of Plant Biology
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• 제14권3호
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• pp.21-28
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• 1971

Dry matter production, leaf area growth and total nitrogen changes were studied in Glycine max. soybean communities, which were grown in sandy loam soils controlled to provide various moisture levels, i.e., 5-7%(level 1), 8-10%(level 2), 11-13%(level 3), 14-15%(lev디 4), 17-20%(level 5) and 22-24%(level 6). A summary of the results is shown. The maximum dry matter production of leaves, stems and nodules and the maximum leaf area per unit area were at level 5, but the maximum of root dry matter production was at level 4. Total nitrogen content of the soybean plant decreased with growth, but each level of soil moisture content also showed a little difference. Water content of the plant decreased with plant age and soil water deficiency, especially in roots and nodules. Nodule formation increased in proportion to soil moisture content. total nitrogen content of the soil on which the soybeans grew, increased from 0.23% before sowing to 0.30% at 100 days after sowing. It seems that soil water content acts as a linear factor in the elongation or dry weight increase of shoots and roots until increasing to level 5. Considering the pattern of plant growth through analysis of the shoot and root dry weight ratio, or the photosynthetic organ and non-photosynthetic organ dry weight ratio, the asymptote of plant growth at a high soil water content exceeded that at a low soil water content.

• Journal of the Korean Society of Visualization
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• 제22권1호
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• pp.34-39
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• 2024

With the fine particulate matter (PM) poses a serious threat to public health and the environment. The ultrafine PM in particular can cause serious problems. This study investigates the effectiveness of a submicron dry fog system in removing fine PM. Two methods are used to create fine dust particles: burning incense and utilizing an aerosol generator. Results indicate that the dry fog system effectively removes fine dust particles, with a removal efficiency of up to 81.9% for PM₁₀ and 61.9% for PM_2.5 after 30 minutes of operation. The dry fog, characterized by a mean size of approximately 1.5 ㎛, exhibits superior performance in comparison to traditional water spraying methods, attributed to reduced water consumption and increased contact probability between water droplets and dust particles. Furthermore, experiments with uniform-sized particles which sizes are 1 ㎛ and 2 ㎛ demonstrate the system's capability in removing ultrafine PM. The proposed submicron dry fog system shows promise for mitigating fine dust pollution in various industrial settings, offering advantages such as energy consumption and enhanced safety for workers and equipment.

• Journal of Animal Science and Technology
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• 제47권6호
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• pp.1075-1080
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• 2005

The objective of this experiment was conducted to evaluate the effect of various legumes in mixtures: AA mixtures(orchardgrass 40%+tall fescue 25%+Kentucky bluegrass 15%+alfalfa 20%), RC mixtures (orchardgrass 40% + tall fescue 25% + Kentucky bluegrass 15% + red clover 20%) and WC mixtures (orchardgrass 50% + tall fescue 25% + Kentucky bluegrass 15% + white clover 10%). The field trials were conducted from 2000 to 2003 at Chungnam National University in order to evaluate the dry matter yield and forage quality on different legumes in mixtures. The dry matter yield was significantly higher in WC mixtures than in other mixtures(p<0.05). In the chemical composition, the content of crude protein and dry matter digestibility were higher in WC mixtures than in other mixtures. However, the content of fibrous constituents of WC mixtures was lower than in other mixtures. The yields of crude protein dry matter and digestible dry matter were significantly higher in WC mixtures than in other mixtures. In botanical composition of alfalfa, red clover and white clover in each mixture were maintained 21%, 36% and 48% respectively, at the last cutting time in 2003. The results of this experiment indicated that WC mixtures were more effective in enhancing the DM yield and forage quality, but it needs to control the optimum botanical composition of WC.

• Journal of The Korean Society of Grassland and Forage Science
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• 제15권2호
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• pp.93-100
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• 1995

This experiment was carried out to investigate how to effect the application of nitrogen, phosphate and potassium on the vegetation and dry matter yield in the mixed sward of orchardgrass and crabgrass (Digitaria sanguinalis [L.] Scop.). The experimental sward wa5 consisted of eight plots of non-application, P, K, PK, N. NK, NP and NPK. These plots were sown with seeds mixture of orchardgrass 17.5 kglha and crabgrass 17.5 kg/ ha on 22 April 1975 in the forage experimental field of Kangwon National University, Chunchon, Korea, and were cut four times from 6 July to 18 November 1975. The results obtained were summarized as follows: 1. In orchardgrass density measured after summering, the plot of nitrogen applied without phosphate marked only 3 1.0% of the plot of nitrogen applied with phosphate while in crabgrass density measured at that time the plot of nitrogen applied without phosphate marked as high as 112.5% of the plot of nitrogen applied with phosphate. 2. Application of phosphate and potassium improved wintering record of orchardgrass. In orchardgrass density measured after wintering, the plot of nitrogen applied without phosphate marked only 9.7% of the plot of nitrogen applied with phosphate, and the plot of NP applied without K marked 63.6% of the plot of NP applied with K. 3. In surface coverage of orchardgrass, in midsummer any plot applied with nitrogen regardless of accompanying with or not with phosphate wa5 0%, but in autumn the plot of nitrogen applied with phosphate was 56-58% and the plot of nitrogen applied without phosphate was 5%. While after wintering the plot of nitrogen applied with phosphate was 28-37% though the plot of nitrogen applied without phosphate was only 0.3-0.6%; the application of phosphate improved summering and wintering record of orchardgrass. 4. Application of phosphate demonstrated remarkable effect on increasing dry matter yield in orchardgrass. In year total yield of orchardgrass, the plot of nitrogen applied without phosphate marked as low as 11.3% of the plot of nitrogen applied with phosphate, but in crabgrass the plot of nitrogen applied without phosphate was almost equal to the plot of nitrogen applied with phosphate showing 97.5% of this plot. 5. Application of potassium was not effective on increasing dry matter yield of orchardgrass but its application was effective on increasing dry matter yield of crabgrass. In dry matter yield of orchardgrass significant difference was not found between NP plot and NPK plot, but in dry matter yield of crabgrass NPK plot recorded significantly higher yield compared with NP plot (p<0.05). 6. In botanical composition of the plot of nitrogen applied with phosphate, crabgrass recorded 46.5-50.5% in early summer (July) but in midsummer (August) it dominated the plot recording 85.6-91.2%. 7. In botanical composition based on the year total yield, in the plot of nitrogen applied with phosphate orchardgrass marked 21.7-26.2% and crabgrass recorded 73.8-78.370, but in the plot of nitrogen applied without phosphate orchardgrass marked only 3.5% being overwhelmingly dominated by crabgrass which recorded 96.5%. 8. Application of nitrogen not accompanied with phosphate strengthened competitive power of the crabgrass unilaterally, making orchardgrass be oppressed fatally by the crabgrass.

• Journal of The Korean Society of Grassland and Forage Science
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• 제23권3호
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• pp.187-192
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• 2003

This study was conducted to investigate dry matter yield and quality of six turf grasses, and thus to apply its result into making mixed species in the mixtures. The six turf grasses were Kentucky bluegrass(Newport), red fescue(Salem), creeping bentgrass(Crenshaw), perennial ryegrass(Palmer Ⅱ), tall fescue(Rebell Jr.) and redtop(Barricuda). This experiment was carried out for 3-years at grassland experimental field of Chungnam National University. The dry matter(DM) yield obtained in tall fescue and redtop was higher than those of the other species(p<0.05). Consideration of crude protein content and dry matter digestibility(DMD), the species of high quality compared to the other species were creeping bentgrass, perennial ryegrass, and Kentucky bluegrass. The crude protein dry matter yield was higher in Kentucky bluegrass and redtop, it was lower in red fescue(p<0.05). On the other hand, digestible dry matter(DDM) yield was higher in tall fescue and redtop, but lower in creeping bentgrass and red fescue(p<0.05). Based on the result mentioned above, therefore, it is suggested that turf grasses such as tall fescue, Kentucky bluegrass and redtop are recommended as species of turf grass which could be used as bottom grasses in mixtures.

• Journal of The Korean Society of Grassland and Forage Science
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• 제41권1호
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• pp.1-9
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• 2021

In the winter forage study, Italian ryegrass(IRG) and barley were selected. In 2018, the dry matter yield of IRG was 16,915kg per ha under the Agrivoltaic System; this was a little more than 16,750kg per ha of outdoors. On the contrary, the dry matter yield of barley was slightly less under the Agrivoltaic System than that of outdoors. In 2019, the dry matter yield under the Agrivoltaic System was 12,062kg per ha for IRG and 12,195kg per ha for the barley; this was 5.4% and 11.5% less than that of outdoors, respectively. In the summer forage study, corn and sorghum×sudangrass were selected. In 2019, the dry matter yield of corn under the Agrivoltaic System was 13,133kg per ha which was 17% less than that of outdoors. The dry matter yield of sorghum×sudangrass was 12,450kg per ha, which was 82.5% of that of outdoors. In 2020, the dry matter yield of corn under the Agrivoltaic System was 8,033kg per ha which was 7.9% less than that of outdoors. The dry matter yield of sorghum×sudangrass was 5,651kg per ha, which was 11.4% less than that of outdoors.

• Journal of The Korean Society of Grassland and Forage Science
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• 제43권2호
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• pp.88-94
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• 2023

This study was conducted to analyze and compare the dry matter yield of Italian ryegrass (IRG) cultivated under monoculture and mixed culture system to recommend suitable varieties that can be cultivated. Italian ryegrass cultivars, Green Fram (GF, extremely early-maturing), Kowinearly (KE, early-maturing), Kowinmaster (KM, mild-maturing), and Hwasan 104 (H104, late-maturing), were used for mono or mixed cultivation. The average monthly temperature in Cheonan over the past 30 years tended to be similar, but that in November and March are judged to be abnormal weather. The dry matter yield of GF+H104 was significantly higher during harvest than that of GF (p<0.05). The dry matter yields of KE and KE+KM were significantly higher during harvest than the output standards of KE and KM. There was no significant difference between the dry matter yield of H104 and KM (p>0.05), but KM had the highest yield of 16,763.1 kg/ha. Analysis showed that the highest dry matter yield during IRG harvest was obtained under monoculture and KE+KM mixed culture. Because the occurrence frequency of abnormal weather such as drought during spring is increasing recently, it is judged that IRG cultivation using early and middle growth is necessary to prepare for abnormal weather.

• Journal of The Korean Society of Grassland and Forage Science
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• 제12권1호
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• pp.67-70
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• 1992

The experiment was conducted to evaluate the effect of the different seeding date on the dry matter yield and chemical composition of oat for forage. The crops wrc sccdcd on August 3l(lirst). Scptember IO(second). and September 20(third seeding date) and were taken on November 24, 1991. The results are summarized as follows : 1. The plant heights were 68, 54 and 40 cm at first, second, and third seeding date, respetively. 2. Dry matter (DM) content decreased with delaying seeding date from first to third seeding date. DM varied from 18.6 to 14.9 %. 3. Leaf weight ratio increased with delaying seeding date from first to third seeding date, varied from 51 to 67 %, but stems decreased from 49 to 33 %. 4. The dry matter yields per ha decreased with delaying seeding date: it was 5.670. 3.960 and 2.310kg at first, second and third seeding date. Significant differences has been obtained among date(P<. 05). 5. The content of crude protein increased with delaying seeding date from first to third seeding date. varied from 16.3 to 22.6%. but NDF and ADF content decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• 제45권2호
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• pp.128-133
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• 2000

This study was carried out to investigate the effect of forms and levels of nitrogen fertilizer on plant growth and essential oil production of Agastache rugosa. Calcium nitrate had more influenced on length and width of leaves and lateral branch length than did urea. When nitrogen fertilizer level was increased from 12 kgN/I0a to 24kgN/I0a, plant growth was stimulated and dry matter of leaf and inflorescence were increased. Top dry matter of plant with calcium nitrate treatment (38.4 g) was heavier than that of urea treatment (32.8 g). Interactions among accession and nitrogen form and nitrogen rate were not significantly different for top dry matter. The forms and rate of nitrogen fertilizer did not affect estragole content. The estragole contents was higher in leaf (91.8%) than that of inflorescence (81.3%). While the essential oil content was not affected by different nitrogen forms, nitrogen level affected the essential oil contents positively by increasing dry matter. Essential oil yield was not affected by accession or nitrogen form, but by nitrogen rate. With increasing N application from 12kgN/I0a to 24 kgN/I0a, essential oil yield was increased by 95.8 %.

• Journal of The Korean Society of Grassland and Forage Science
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• 제8권1호
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• pp.1-7
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• 1988

This experiment was carried out to determine the effect of grazing and cutting system in the seven different seed mixture plots on the dry matter yield and botanical composition from October 1983 to November 1986 at 200m above the sea level in Cheju. The results obtained are summarized as follows: 1. Dry matter yield was increased more cutting system than that of grazing system during the first and second harvest year (P<0.01), but at the third harvest year grazed plot was increased (P<0.05). 2. Three-year average dry matter yield tended to be relatively higher with tall fescue mixture plots (T4 and T7) than without tall fescue mixture plots. 3. In botanical composition of the seed mixtures, orchardgrass was observed to be more dominate in cutting system, while perennial ryegrass was increased in grazed plots. 4. Tall fescue was dominated about 70-80% at the third harvest year, in the plot of both grazing and cutting system. 5. The percentage of ladino clover was slightly increased in grazed plot compared with cutting plots. However those of alfalfa and red clover were not influenced by grazing and cutting system.