• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.2
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• pp.41-50
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• 2013

We investigated influence of continuous application of gypsum(G:$CaSO_4{\cdot}2H_2O$), popped rice hulls(H) and zeolite(Z) on soil aggregation of reclaimed silt loam soils. The application rates amended to silt loam from reclaimed soils at Saemangeum of Mangyeong were varied as follows; 1550(G1), 3100(G2), 6200 (G3) gypsum kg/10a, 1000(H1), 2000(H2), 3000(H3) popped rice hulls kg/10a, and 200(HZ1), 400(HZ2), 800(HZ3) zeolite kg/10a added to 1500 popped rice hulls kg/10a, respectively. In addition, the bermuda grass was growing, and the soil aggregates were analyzed for 60, 90 and 120 days after treatments(DAT). At 60 DAT, the effect of treatment was in order of G>H${\geq}HZ$, and the 1550kg/10a(G1) was the highest as 52.48%. At 90 DAT, the effect of treatment was also in order of G>H>HZ. Those was 3.78-3.12, 2.03-3.03 and 1.79-2.57 times in compared with the control, respectively. At 120 DAT, the effect of treatment was similar continued in order of G>H>HZ. Those was 3.00-2.20, 1.06-1.64 and 0.92-1.23 times in compared with the control, respectively. In conclusion, we found that the continuous application for two year of gypsum, popped rice hulls and zeolite was excellent above the 1 year, and the effect of the treatment for soil amendments of reclaimed silt loam soil was excellent in order of G>H>HZ.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.172-182
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• 2006

This study was designed to assess molinate fate in the lysimeter by measuring the total radioactivity in the leachate, evolved $^{14}CO_2$, and $^{14}C$-residues in soil and rice plant. The amounts of applied $^{14}C$ in the leachate from the lysimeter for 20 weeks were 1.05% in 2.31 pore volume (217,465 mL) at the first and 0.34% in the second year, respectively. The amount of $^{14}CO_2$ evolved from the lysimeter accounted for 6.47% and 0.03% of applied $^{14}C$ in the first and second year. The $^{14}C$-activities in the soil layer of the lysimeter were distributed 18.0% (1st) and 13.3%(2nd) in the depth of 0 to 10 cm, 4.3 (1st) and 1.1% (2nd) in the depth of 10 to 20 cm. Most of the applied $^{14}C$ was detected in the top 20 cm soil layer. Total $^{14}C$ in rice plants grown at lysimeter were detected 11.46% of applied $^{14}C$. 11.11% in straw, 0.24% in brown rice grain, 0.08% in chaff and 0.03% in ears were distributed in the first year. Consequently, environmental fate of molinate using lysimeter simulating a paddy rice field were investigated 25.24% in soil, 11.64% in rice plant, 1.05% in leachate, 6.74% in evolved $^{14}CO_2$ and 0.02% in volatilized organic chemicals in the first year.

• The Korean Journal of Pesticide Science
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• v.16 no.3
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• pp.236-241
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• 2012

The characteristics of chlorpyrifos was studied to clarify the effect of the cultivation season, spray intervals, spray volume and concentration on residues in chilli and sweet peppers cultivated under greenhouse condition. Residue levels of chlorpyrifos detected in chilli pepper fruit cultivated were 1.5 to 2.7 times higher in winter(February-March) than those in summer(June-July). During winter season residue levels of chlorpyrifos in chilli peppers were 6.9~3.2 times higher than those in sweet peppers for 10 days after 3 times application with 7 days interval. Residue levels in chilli pepper were from 2.070 mg/kg at 1 day to 0.929 mg/kg at 10 day, while those in sweet pepper were from 0.302 mg/kg to 0.291 mg/kg. Residue levels in sweet pepper to which are 3 times applied with 7 days interval were from 0.302 mg/kg at 1 day to 0.291 mg/kg at 7 day, and the residue levels in sweet pepper which are 3 times applied with 3 days interval were from 0.498 mg/kg at 1 day to 0.470 mg/kg at 7 day. Residue levels of chlorpyrifos in the sweet peppers applied by double concentration were 2.5 times higher than those sprayed by normal standard amounts diluted in double volume.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.10a
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• pp.111-124
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• 2003

Processes that cause immobilization of contaminants in soil are of great environmental importance because they may lead to a considerable reduction in the bioavailability of contaminants and they may restrict their leaching into groundwater. Previous investigations demonstrated that pollutants can be bound to soil constituents by either chemical or physical interactions. From an environmental point of view, chemical interactions are preferred, because they frequently lead to the formation of strong covalent bonds that are difficult to disrupt by microbial activity or chemical treatments. Humic substances resulting from lignin decomposition appear to be the major binding ligands involved in the incorporation of contaminants into the soil matrix through stable chemical linkages. Chemical bonds may be formed through oxidative coupling reactions catalyzed either biologically by polyphenol oxidases and peroxidases, or abiotically by certain clays and metal oxides. These naturally occurring processes are believed to result in the detoxification of contaminants. While indigenous enzymes are usually not likely to provide satisfactory decontamination of polluted sites, amending soil with enzymes derived from specific microbial cultures or plant materials may enhance incorporation processes. The catalytic effect of enzymes was evaluated by determining the extent of contaminants binding to humic material, and - whenever possible - by structural analyses of the resulting complexes. Previous research on xenobiotic immobilization was mostly based on the application of $^{14}$ C-labeled contaminants and radiocounting. Several recent studies demonstrated, however, that the evaluation of binding can be better achieved by applying $^{13}$ C-, $^{15}$ N- or $^{19}$ F-labeled xenobiotics in combination with $^{13}$ C-, $^{15}$ N- or $^{19}$ F-NMR spectroscopy. The rationale behind the NMR approach was that any binding-related modification in the initial arrangement of the labeled atoms automatically induced changes in the position of the corresponding signals in the NMR spectra. The delocalization of the signals exhibited a high degree of specificity, indicating whether or not covalent binding had occurred and, if so, what type of covalent bond had been formed. The results obtained confirmed the view that binding of contaminants to soil organic matter has important environmental consequences. In particular, now it is more evident than ever that as a result of binding, (a) the amount of contaminants available to interact with the biota is reduced; (b) the complexed products are less toxic than their parent compounds; and (c) groundwater pollution is reduced because of restricted contaminant mobility.

• Journal of Plant Biotechnology
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• v.42 no.1
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• pp.25-33
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• 2015

A PyrcpPR-10 gene with differentially expressed was isolated by using the suppression subtractive hybridization assay between '93-3-98' (highly resistant against scab caused by Venturia nashicola) and 'Sweat Skin'(highly susceptible) and analyzed the expression pattern according to organs and cultivars. The full length of PyrcpPR-10 was cloned as 743bp with 480bp's ORP, and was determined to encode a protein of 159 amino acid residues. On analyzing PyrcpPR-10 gene sequence compared with resistant and susceptible cultivars, 'Hwangsilri' (resistant), 'Gamcheonbae' (moderately resistant), 'Wonhwang' (moderately susceptible), 'Niitaka' (highly susceptible), and 'Sweat Skin' (highly susceptible) had identical gene sequence but 'Bartlett' (highly resistant) showed partly different sequences. The deduced amino acid sequence showed 64 ~ 98% homology and had the GXGGXG motif to known amino acid of other plants PR-10 by the BLAST X analysis. Among several organs or tissues, petal was showed highest expression level of PyrcpPR-10 gene followed by leaf, floral axis, bud, and bark. The expression level of PyrcpPR-10 gene was dramatically increased at 24 hr after inoculation in all cultivars and also up-regulated in accordance with resistant degree of cultivars. While resistant cultivars ('Bartlett', '93-3-98', and 'Hwangsilri') induced relatively high expression level of PyrcpPR-10 gene, susceptible cultivars ('Niitaka', and 'Sweat Skin') showed low expression level. PyrcpPR-10 gene is assumed that it is directly connected with defense mechanisms to pear scab.

• Journal of Life Science
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• v.19 no.1
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• pp.101-110
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• 2009

The regulation of gene expression plays an important role in cell cycle controls. In this study, a novel $mas2^+$ (mitosis associated protein) gene, a homolog of human SMARCAD1 was isolated and characterized from a fission yeast Schizosaccharomyces pombe (S. pombe) using gene-specific polymerase chain reaction. The isolated gene contained a complete open reading frame capable of encoding 922 amino acid residues with a typical promoter, as judged by nucleotide sequence analysis. It was also found that an SNF2 domain is located, which is involved in the chromosome remodeling. The quantitative analysis of the $mas2^+$ transcript against $adh1^+$ showed that the expression level of $mas2^+$ is high before septum formation in S. pombe. When $mas2^+$ null mutant cells were grown at 27 and $35^{\circ}C$, the cytokinesis of $mas2^+$ null mutant was greatly delayed and a large number of multi-septate and mis-segregated cells were produced. In addition, the number of multi-septate cells significantly increased. When cells were cultured in YES rich medium to increase proliferation, the abnormal phenotypes $mas2^+$ null mutant dramatically increased. These phenotypes could be rescued by an over-expression of the mast gene. The Mas2 protein localized in the nuclei of S. pombe, as evidenced by Mas2-EGFP signals. These results suggest that the $mas2^+$ is homologous to human SMARCAD1 gene and involved in septum formation and chromosome remodeling control.

• Applied Biological Chemistry
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• v.8
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• pp.101-111
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• 1967

Daily doses of phenylmercuric acetate arranged in $30{\gamma}\;(group\;I)$, 3{\gamma}\;(group\;II)$ and $0.3{\gamma}\;(group\;III)$ were administered respectively to rabbits for 90 days. The chief histopathological changes in the organs and the analytical data on mercury residues in the excretion and liver were as follows. 1. Kidney: In group I, severe degrees of vacuolization and cloudy swelling were occurred in the epithelial cells of proximal convoluted tubules and severe cloudy swelling and coagulative necrosis were observed in the proximal straight tubules. There were many hyaline casts in the collecting tubules. In group II, moderate degrees of vacuolization and cloudy swelling were observed in the epithelial cells of proximal convoluted tubules and moderate cloudy swelling and coagulative necrosis were encountered in the proximal straight tubules. A little numbers of hyaline casts were located in the lumen of collecting tubules. In group III, slight degree of cloudy swelling were observed in the epithelial cells of proximal convoluted and straight tubules. 2. Liver: In group I, cloudy swelling, fatty changes and coagulative necrosis were observed in the central zone of hepatic lobules. Dissociation of hepatic cell cords was encountered. Hyperplsia of hepatic cells were remarkable in group II. No Pathological changes were observed in group III. 3. Spleen: Deposition of hemosiderin pigment was prominant in group I and small amount of the pigment was observed in group II. There were no pathological changes in group III. 4. Adrenal, colon and heart: No pathological changes were detected in all 3 groups. 5. In an average about 76.5% of mercury was excreted from group I, 85.4% from group II and 79.8% from group III. 6. Mercury content in the liver was 0.0348 g in group I, 0.00378 g and 0.00066 g in group II and group III respectively. 7. In general, as to increased mercury doses the concentration of mercury accumulation in the liver became higher, how·ever, the accumulation quantity against a total amount of mercury doses showed an adverse trend. In other word, the quantity of mercury accumulation was not increased proportionately by higher dose of mercury.

• Research in Plant Disease
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• v.22 no.3
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• pp.145-151
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• 2016

Chemical fungicides have reduced Fusarium head blight (FHB) severity. However, by the effects of fungicide residues, they can only be used up to 30 days before time of harvest. Therefore, the development of new biofungicides that are applicable until harvest is required. In order to select plant extracts having antifungal activity against Fusarium graminearum for the control of FHB, we investigated the inhibitory effects of 225 medicinal plant extracts on spore germination of F. graminearum. Of these plant extracts, the methanol extract of Cirsium japonicum (CJ) roots showed the strongest antifungal activity. Through solvent partitioning, repeated column chromatography, and spore germination bioassay, two chemicals were purified and then their chemical structures were identified as ciryneol C (CC) and 1-heptadecene-11,13-diyne-8,9,10-triol (HD-ol) which are polyacetylene substances. Two active compounds effectively inhibited the germination of F. graminearum macroconidia; HD-ol ($IC_{50}$ of $3.17{\mu}g/ml$) showed stronger spore germination inhibitory activity than that of CC ($IC_{50}$ of $28.14{\mu}g/ml$). In addition, the wettable powder type formulation of ethyl acetate extract of CJ roots suppressed the development of FHB in dose-dependent manner, with control values of 78.92% and 31.56% at 250- and 500-fold dilutions, respectively. Combining these findings suggest that the crude extract of CJ roots containing polyacetylene compounds could be used as botanical fungicide for the control of FHB.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.85-98
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• 1995

Six malformin B's produced by Aspergillus niger van Tiegh. were separated by HPLC. Their structures determined by the methods of amino acid analyses, mass spectrometry, and two-dimensional NMR were revealed as cyclic pentapeptides structurally related to malformin $A_1$. Both the NMR and MS/MS data suggest that the respective structures of separated malformin B's were as follows; cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-allo-Ile for $B_{1a}$, cyclo-D-Cys-D-Cys-L-Val-D-Leu-L-Leu for $B_{1b}$, cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Leu for $B_2$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Leu for $B_3$, cyclo-D-Cys-D-Cys-L-Val-D-Ile-L-Ile for $B_4$, and cyclo-D-Cys-D-Cys-L-Val-D-Val-L-Ile for $B_5$. Among the malformin B's, the structure of $B_{1b}$ was the same as that of malformin $A_3$ or C. All the malformin B's showed physiological activities in the two assay systems using corn(Zea mays L.) roots and mung bean(Phaseolus aureus Roxb.) hypercotyl segments. The malformin B's with molecular weight 529 were more effective for inducing corn root curvature than those with molecular weight 515. The difference in molecular weight of malformin B's, i.e., the retention time on HPLC, results in the polarity change of the whole malformin molecule which affects the revealation of the malformin activities. In addition, the disulfide form of the malformin B's gives the rigidity of the molecule, whereas the combination of the fourth and the fifth amino acid residues provides the optimal three-dimensional configuration to the malformin receptor of plants. Presumably, these two factors are appeared to be essential for the greatest physiological activity of malformin B's. malformin $B_{1a}$ caused the corn root curvature by 90% at a concentration of $0.25{\mu}M$. However, such differential activities with molecular weight of 529 or 515 of malformin B's were not found in the mung bean hypercotyl segment test. Maximum stimulation of mung bean hypercotyl growth was observed at $0.1{\mu}M$ concentration of malformin B's. The growth of the segments treated with $B_5$ was 154% greater than that of the control.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.343-350
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• 2007

Three different experiments were carried out to investigate the runoff and erosion losses of endosulfan from sloped-field by rainfall. The mobility of endosulfan and which phase it was transported by were examined in adsorption study, the influence of rainfall pattern and slope degree on the pesticide loss were evaluated in simulated rainfall study, and the pesticide losses from soybean-grown field comparing with bare soil were measured in field lysimeter study. Adsorption parameter (K) of endosulfan ranged from 77 to 131 by adsorption method and K values by the desorption method were higher than those by the adsorption method. By the SSLRC's classification for pesticide mobility endosulfan was classified as non-mobile class ($K_{oc}>4,000$). Runoff and erosion loss of endosulfan by three rainfall scenarios ranged from 3.4 to 5.6%and from 4.4 to 15.6%of the amount treated. Endosulfan residues were mainly remained at the top 5 cm of soil depth after the simulated rainfall study. Pesticide loss in case of 30%-slope degree ranged from 0.6 to 0.9 times higher than those in case of 10%-slope degree. The difference of pesticide runoff loss was related with its concentration in runoff water and the difference of pesticide erosion loss would related closely with the quantity of soil eroded. Endosulfan losses from a series of lysimeter plots in sloped land by rainfall ranged from 5 to 35% of the amount treated. The erosion rate of endosulfan from soybean-plots was 66% of that from bare soil plots. The effect of slope conditions was not great for runoff loss, but was great for erosion loss as increasing to maximum $4{\sim}12$ times with slope degree and slope length. The peak runoff concentration of endosulfan in soybean-plots and bare soil plots ranged from 8 to 10 and from 7 to $9{\mu}gL^{-1}$ on nine plots with different slope degree and slope length. Therefore the difference of the peak runoff concentrations between bare soil plots and soybean-plots were not great.