• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.221-224
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• 1999

A field experiment was carried out to observe the weed control effects of vetch and to evaluate vetch characteristics on clay loam soil in no-till direct-sown rice-vetch cropping systems. The effects of weed control, forage productivity, and N content of vetch plants were investigated. With the progress of plant growth, density of Chinese milk vetch (Astragalus sinicus L.) gradually decreased, but densities of foxtail and other weeds decreased steeply due to the depression by the over-shaded vetch canopy in a no-till direct-sown rice-vetch cropping paddy field. The vetch density in tillage systems was lower than in notillage cropping systems. Lower vetch density occurred with an increase in foxtail density and other weeds. Weed control effect increased by the progress of vetch growth, which indicated that the vetch canopy over-shaded the weeds. Vetch straw was degraded rapidly submergence after with water at the time of wet sowing of rice. Early harvesting of vetch seed resulted in lower seed germination. To acquire enough seedlings without re-sowing, the harvesting of seed should be delayed at least 28 days after the flowering stage in order to ensure the vetch population is sustainable in a no-till direct-sown rice-vetch cropping system. In order to improve the survival of vetch plants, vetch seeds should germinate from the heading .stage to before the full-ripening stage of rice plants. To enhance the percent of over-wintering survival, vetch seeds should germinate no later than the end of October in southern Korea. The dry weight of vetch plants increased with the progress of vetch growth until the flowering stage but N content decreased for 30 days from before the flowering stage (2.9%) until the ripening stage (1.8%). We concluded that Chinese milk vetch could have an effect on weed control before the flowering stage, sustainability without re-sowing of seed annually, and effective green manure for rice pre-crop in no-till direct-sown rice-vetch relay cropping systems.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.1
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• pp.101-109
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• 2016

This is the fundamental research on restoring damaged vegetation areas in the vicinity of DMZ using local native plant species. This research is aimed at identifying effective plant growth regulators (PGR) for seed germination and seedling growth of mountain mulberry, and developing effective methods for managing its germination and growth. Mountain mulberry seeds were collected from the regions in the DMZ vicinity, and tests with seven treatments using four PGRs including $GA_3$, kinetin, ABA and NAA, were conducted. The germination rate was calculated in two different ways of both in a growth chamber and in a greenhouse after seven days observation, and the growth characters such as leaf width/length, seedling width/length and fresh/dry weight, have been surveyed in a greenhouse for three months. Although in the growth chamber the highest germination rate was shown at a group with the kinetin treatment, it was not significantly different to that of the control group. Groups with ABA or NAA presented relatively low germination rates. As for the greenhouse test, the germination rates of all groups ranged 20~30% without significant difference each other, the reason of which might be due to low absorption by the effect of a soil drench method used in this study. The entire growth characters with the treatments of $2.15mg{\cdot}L^{-1}$ of kinetin and $10mg{\cdot}L^{-1}$ of $GA_3$ were significantly different to the control. NAA treatment only showed better growth of seedling width compared to the control. Consequently, the most effective PGRs for the germination and growth of mountain mulberry near the DMZ was kinetin. Further research on examining the most effective concentration of them was needed.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.211-216
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• 2006

This study was carried out to investigate the effect of greenhouse cooling by a geothermal heat pump system on greenhouse temperature and growth of vegetable transplants in summer season. Greenhouse air temperature in day time was $3-4^{\circ}C$ lower in fog plus shading system than in shading, while in night time that was $5-7^{\circ}C$ lower in geothermal heat pump (GHP) plus shading system compared to shading or fogplus shading. system. Plant height of cucumber, tomato and hot pepper transplants was shortened in GHP plus shading compared to shading or fog plus shading system. And Leaf area and dry weight were slightly decreased in GHP plus shading compared to the other systems. Therefore, healthy transplant index on cucumber, tomato and hot pepper was higher in GHP plusshading than in shading or fogplusshading system.

• Journal of Applied Biological Chemistry
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• v.44 no.1
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• pp.16-19
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• 2001

Soybean plants(Glycine max [L.] merr.) inoculated with Bradyrhizobium japonicum MN110 were grown in growth chambers under 400 or $800{\mu}l{\cdot}l^{-1}$ atmospheric $CO_2$ and harvested at 25, 28, 32, and 35 DAT to examine the effect of $CO_2$ enrichment on phosphorus accumulation, uptake, and utilization efficiency during vegetative growth. Phosphorus concentration in leaf was lower in high $CO_2$ plant by 47% at 25 DAT and 34% at 35 DAT than those in the control plant but phosphorus concentrations in stem, root and nodule were not affected by $CO_2$ enrichment. Total phosphorus accumulation increased 3.9-fold in high $CO_2$ plant and 3.2-fold in the control plant between 25 and 35 DAT. Elevated $CO_2$ caused a decrease in the whole plant phosphorus concentration by 35%, which was due almost entirely to a decrease in the phosphorus concentration of leaves. $CO_2$ enrichment increased phosphorus utilization efficiency in the whole plant by 70% during the experimental period. Plants exposed to high $CO_2$ had larger root systems than under ambient $CO_2$, but high $CO_2$ plants had lower P-uptake efficiency. Averaged over four harvests, plants at high $CO_2$ had 38% larger root mass that was more than offset the 20% lower efficiency of P-uptake and accounted for increased phosphorus accumulation by high $CO_2$ plant. These results suggest that the reduced phosphorus concentration in soybean plant under $CO_2$ enrichment may be an acclimation response to high $CO_2$ concentration or enhanced starch accumulation, resulting in the plants to have a lower phosphorus requirement on a unit dry weight basis or a high phosphorus utilization efficiency under these conditions.

• Journal of Applied Biological Chemistry
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• v.54 no.2
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• pp.120-125
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• 2011

In order to exploit Methylobacterium oryzae CBMB20 as of plant growth promoting agent, different inoculation methods have been evaluated. The present study aimed to evaluate soil, foliar, and soil+foliar inoculations of M. oryzae CBMB20 to improve the growth, fruit yield, and nutrient uptake of red pepper (Capsicum annuum L.) under greenhouse conditions. The population range of green fluorescent protein (gfp)-tagged M. oryzae CBMB20 using the three inoculation methods was 2.5-2.9 ${\log}_{10}$ cfu/g in the rhizosphere and 4.5-6.0 ${\log}_{10}$ cfu/g in the phyllosphere of red pepper plants. Confocal laser scanning microscopy results confirmed the colonization of M. oryzae CBMB20 endophytically on leaf surface. Plant height, fruit dry weight, and total biomass were significantly higher ($p{\leq}0.05$) in all M. oryzae CBMB20 inoculation methods as compared to non-inoculated control. Furthermore, uptake of mineral nutrients such as N, P, K, Ca, and Mg in red pepper plants in all M. oryzae CBMB20 inoculation methods was higher than in non-inoculated control. Comparative results of inoculation methods clearly demonstrated that soil+foliar inoculation of M. oryzae CBMB20 lead to the highest biomass accumulation and nutrient uptake which may be due to its efficient colonization in the red pepper rhizosphere and phyllosphere.

• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.66-75
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• 2006

This study was conducted to understand the biomass and the energy content of 24-year-old Pinus koraiensis stand planted in Mt. Wolak, Chungcheongbuk-do, Korea. Nine sample trees were selected and harvested for the study. Stem, bark, branches and leaves were weighed respectively with the stratified clipping method, and analyzed for productive structure. The allometric regression equations between dry weight of each component and $D^2H$ were obtained to estimate the total biomass of aboveground (47.0 ton/ha) and other parts (56.5% from stemwood, 9.1% from stembark, 0.5% from current twigs, 18.4% from live branches, 2.6% from current leaves, and 12.9% from previous leaves). Annual net production of aboveground was 6.0 ton/ha/yr, and the ratios of stemwood, stembark, current twigs, live branches, and current leaves to that of aboveground were 49.8%, 7.3%, 3.5%, 18.6%, and 20.8%, respectively. Energy content of aboveground was 1,028 GJ/ha, and annual energy content was 133 GJ/ha/yr. Leaf area index (LAI) of P. koraiensis plantation was 20.2 in Mt. Wolak.

• Journal of Ecology and Environment
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• v.39 no.1
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• pp.81-90
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• 2016

This study was to investigate the effect of salt stress on physiological characteristics such as plant growth, photosynthesis, solutes related to osmoregulation of Beta vulgaris. A significant increase of dry weight was observed in 50 mM and 100 mM NaCl. The contents of Chl a, b and carotenoid were lower in NaCl treatments than the control. On 14 day after NaCl treatment, photosynthetic rate (P_N), the transpiration rate (E) and stomatal conductance of CO₂ (g_s) were reduced by NaCl treatment. On 28 day after NaCl treatment, the significant reduction in g_s and E was shown in NaCl 200 mM. However, P_N and water use efficiency (WUE) in all NaCl treatments showed higher value than that of control. Total ion contents (TIC) and osmolality were higher than the control. On 14 day after treatment, the contents of proline (Pro) increased significantly in 200 mM and 300 mM NaCl concentration compared with control, whereas on 28 day in all treatments it was lower than that of the control. The contents of glycine betaine (GB) increased with the increase of NaCl concentration. The contents of Na⁺, Cl^-, GB, osmolality and TIC increased with the increase of NaCl concentrations. These results suggested that under severe NaCl stress conditions, NaCl treatment did not induce photochemical inhibition on fluorescence in the leaves of B. vulgaris, but the reduction of chlorophyll contents was related in a decrease in leaf production. Furthermore, increased GB as well as Na⁺ and Cl^- contents resulted in a increase of osmolality, which can help to overcome NaCl stress.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.27-33
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• 1969

This study was carried out to investigate the variation of mulberry yield in various parts of mulberry field. The results obtained from the study are summarized as follows. 1. For all the varieties, higher yield was observed side part than in the middle part. 2. With respect to the direction of field, the side faced south produced the highest yield, which was followed both side parts faced east and west. The side part fated north also produced relatively high yield. 3. No significant difference in yield was obtained between the central part and the near the each side, even the former seemed to be some what higher in yield than the latter. 4. Such a variety as Kaeryangsuban havins small leaves on many twigs with small internodes appeared to have more side effect than the otherwise variety, i.e. Rosang. 5. The variety Kaeryangsuban, showed more side effect in spring than in Autumm, however Rosang showed reversed effect. 6. Similar results were obtained in the leaf dry weight. 7. As a conclusion, it can he an important factor to increase yield to set up the mulberry field in east and west resulting less side effect.

• The Korean Journal of Food And Nutrition
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• v.31 no.4
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• pp.464-470
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• 2018

All the parts of the Cedrela sinensis A. Juss., including the seeds, roots, and leaves, have been known to exert medicinal effects. The C. sinensis and its major compound, quercetin, were previously reported to exhibit the anti-inflammatory and anti-oxidative activities. However, the hepatoprotective effects of the C. sinensis leaves against the alcohol-induced oxidative stress in the HepG2 cells have not been studied. In this study, we investigated the antioxidant activities and analyzed the flavonoid contents of the C. sinensis-leaf extract (CE). The total flavonoid contents of the CE is 1,874.5 mg/100 g dry weight (DW), while the total quercetin 3-O-rhamnoside (quercitrin) contents, which was identified as the major flavonol in the CE, is 1,456.0 mg/100 g DW. In the ethanol-stimulated HepG2 cells, the CE effectively prevented the cytotoxic effect and increased the gene expression of the antioxidant enzymes, such as the heme oxygenase-1 (HO-1) and the glutathion peroxide (GPx). The level of the reactive oxygen species (ROS) production was significantly decreased in the CE-treated HepG2 cells. In conclusion, the C. sinensis extract suppressed the alcohol-induced oxidative stress in the HepG2 cells via the induced GPx and HO-1 gene expressions. It is expected the CE positive effects will likely be attributed to the flavonoids, like the quercetin, within the CE.

• Preventive Nutrition and Food Science
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• v.19 no.3
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• pp.220-226
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• 2014

In the present report, the effects of blanching, steaming, and high temperature/high pressure processing (HTHP) on the amino acid contents of commonly consumed Korean root vegetables, leaf vegetables, and pulses were evaluated using an Automatic Amino Acid Analyzer. The total amino acid content of the samples tested was between 3.38 g/100 g dry weight (DW) and 21.32 g/100 g DW in raw vegetables and between 29.36 g/100 g DW and 30.55 g/100 g DW in raw pulses. With HTHP, we observed significant decreases in the lysine and arginine contents of vegetables and the lysine, arginine, and cysteine contents of pulses. Moreover, the amino acid contents of blanched vegetables and steamed pulses were more similar than the amino acid contents of the HTHP vegetables and HTHP pulses. Interestingly, lysine, arginine, and cysteine were more sensitive to HTHP than the other amino acids. Partial Least Squares-Discriminate Analyses were also performed to discriminate the clusters and patterns of amino acids.