• Korean Journal of Environmental Agriculture
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• v.30 no.4
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• pp.357-366
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• 2011

BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.392-395
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• 2006

The toxic effects of 9 commercially available herbicides on the earthworm, Eisenia fetida (Savigny) were evaluated with recommended dose, 2-fold and 4-fold dose using soil surface spray, immersion and contact filter tests in order to find out whether herbicides actually influence the life of earthworm in the soil or not. In the surface sprayed soil test, the earthworm mortality to nine herbicides were not significantly different from the comparison with the control regardless of level of dose. In the immersion test, the mortality of 4-fold dose was 34% in the napropamide and 64% in the alachlor. In contact filter test, the mortality appeared 80% in alachlor, 37% in napropamide, and 10% in triclopyr at 2-fold dose level and those of 4-fold dose were as follows: napropamide 96%, alachlor 80%, glyphosate 47%, triclopyr 37%, paraquatdichloride 37%; glufosinate ammonium 33%, pyributicarb 10%. As a result of these tests by three methods, the mortality of earthworm in terms of the recommended dose level was no observation about eight herbicides while the napropamide appeared 33% in contact filter test.

• Korean Journal of Environmental Agriculture
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• v.25 no.4
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• pp.297-305
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• 2006

The field lysimeter experiment were undertaken to investigate the runoff and erosion loss of four pesticides from sloped land by rainfall and to assess the influence of pesticide properties, environmental factors and agricultural practices on them. The pesticide losses from soybean planted field and bare field were measured using field lysimeters. Pesticide losses from a series of lysimeter plots of sloped land by rainfall ranged $0.1{\sim}0.6%$ for alachlor, $1.1{\sim}4.5%$ for ethalfluralin, $8{\sim}31%$ for pendimethalin and 0.03% for ethoprophos, which were $1/3{\sim}2.5$ times to them in the simulated rainfall study. The erosion loss rates of pesticides from soybean-plots were $21{\sim}75%$ lower than the ones from bare soil plot. The effect of slope conditions was not great for runoff loss, but for erosion loss increased to maximum $4{\sim}12$ times by sloping degree and slope length. The peak runoff concentration in soybean-plots and bale soil plots were $3{\sim}278{\mu}gL^{-1}\;and\;6{\sim}450{\mu}gL^{-1}$ for alachlor, $1.1{\sim}11.4{\mu}gL^{-1}\;and\;0.9{\sim}16{\mu}gL^{-1}$ for ethalfluralin, $7{\sim}42{\mu}gL^{-1}\;and\;6{\sim}66{\mu}gL^{-1}$ for pendimethalin, and $2{\sim}53{\mu}gL^{-1}\;and\;0.1{\sim}113{\mu}gL^{-1}$ for ethoprophos, respectively, on nine different slope degree and slope length plots. Therefore, the differences of the peak runoff concentration between bare soil plots and soybean-plots were not great.

• Korean Journal of Weed Science
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• v.15 no.3
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• pp.197-205
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• 1995

The objectives of the present study were to find out 1)the differences in growth of radish under foggy and non-foggy condition, 2)the weed competition between radish and major upland weeds including Echinochloa crus-galli, 3)difference in response of radish to herbicide and weed, and finally 4)the fundamental data for the establishment of radish weed control system under locational foggy regions. The research was carried out by tray in greenhouse equipped with Auto Foggy System(SAE KI RIN Co.) and results were summarized as follows. 1. Plant height and shoot fresh weight of radish cultivars(long skirt, delicious altari, green mascot) were not different at the early growth(8 to 38 days after seeding), but increased at 55 days after seeding under foggy condition. Root fresh weight increased only in green mascot cultivar tinder foggy condition. Chlorophyll contents were higher in all the cultivars of radish under foggy condition. 2. Plant height and shoot fresh weight increased at 0 and 20 days of weed competition under foggy condition. Root fresh weight increased at 0, 20 and 35 days of competition under foggy condition. Above 50 days-competition, there was no difference between foggy and non-foggy condition. 3. Napropamide, alachlor and linuron did not show any differences in plant height and shoot fresh weight between foggy and non-foggy condition. Molinate reduced the root fresh weight at 65 days after seeding tinder foggy condition. 4. No difference in weeding efficacy by any herbicides tested was found tinder foggy condition. Weeding efficacy of Aeschynomene indica was reduced under foggy condition.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.188-197
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• 2003

Endocrine disrupting chemicals (EDCs) can alter hormone regulation that control reproductive system in animals. The effects of endosulfan, molinate, and alachlor that suspected to have examined disruption EDCs effect on a fish species of interest, Xiphophorus helleri (swordtail fish), were studied using vitellogenin (Vtg) and aromatase as diagnostic biomarkers. Induction of Vtg proteins was detected by RT-PCR in male fish treated with alachlor, and mixture of endosulfan and molinate in dose response manner. Also, induction of aromatase was detected by RT-PCR in male fish treated with alachlor, endosulfan, and mixture of endosulfan and molinate in sinlilar manner. In this study, swordtail fish exposed to endosulfan or molinate individually did not show any adverse effects. However, Vtg and aromatase expressions and apoptosis were detected in swordtail. fish exposed to the mixture of endosulfan and molinate. These results suggested that low concentrations of mixture of molinate and endosulfan individually do not affect swordtail fish, but may influence genital system, and induce apoptosis.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.144-153
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• 2007

One of the most recent issues facing the pesticides regulatory process is the assessment of the potential for pesticides to leach through soil and appear in groundwater. Since Jeju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water, it is important to identify which pesticides are the most likely to result in groundwater contamination. The objective of this study was to assess groundwater contamination risk of 21 pesticides (12 insecticides, 6 herbicides and 3 fungicides) in Jeju soils using groundwater ubiquity score (GUS). Considering GUS estimated in 21 representative series of Jeju soils, generally herbicides showed relatively higher leaching potentials and insecticides showed lower leaching potentials. Groundwater contamination risk was higher in the order of bromacil > metolachlor > alachlor > linuron pretilachlor > butachlor for herbicides, carbofuran > ethoprophos > diazinone > dimethoate > penthoate > mecarbam > methidathion > endosulfan > fenitrothion > parathion > chlorpyrifos > terbufos for insecticides, and metalaxyl > chlorothalonil > triadimefon for fungicides. Among the tested pesticides alachlor, metolachlor, bromacil, ethoprophos and carbofuran were classified as the pesticides of very high or high groundwater contamination potential. Although the ranking of the leaching potential was essentially determined on the base of the intrinsic properties of the chemicals and environmental properties, variation of the relative groundwater contamination potentials of each pesticides in different soils were not significant. Therefore, the above ranking of groundwater contamination risk would be applied in most of Jeju soils. To lower the possibility of pesticide contamination of groundwater, the use of those pesticides classified as high or very high leaching potential should be strictly regulated in Jeju Island.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.259-259
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• 2005

• The Korean Journal of Pesticide Science
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• v.16 no.1
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• pp.43-53
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• 2012

In order to monitor the levels of pesticides in environment-friendly stalk and stem vegetables and leafy vegetables selling at markets in Korea. A total of 637 (395 organic agricultural products, 242 pesticide-free agricultural products) samples of 21 stalk and stem vegetables and leafy vegetables were collected twice from markets in July and August 2010 in Korea. Pesticide residues in samples were analyzed by multiresidue method for 240 pesticides using GC-ECD/NPD and HPLC-DAD/FLD. The suspected-pesticides were confirmed with a GC-MSD. As a result of analysis, six pesticides were detected from eight samples, representing a detection rate of 1.3% and amounts of pesticide residues in samples were as follows: alachlor 0.043, chlorfenapyr 0.022-0.324, diazinon 0.024, dicofol 0.009-0.138, dithiopyr 0.008, metolachlor 0.025 mg/kg. Their residue levels were below the MRLs. Estimated daily intakes (EDIs) of the pesticides detected from stalk and stem vegetables and leafy vegetables were less than 25% of their acceptable daily intakes (ADIs), representing that residue levels of the pesticides detected were evaluated as safe for consumption. However, five samples containing pesticide residues were unsuitable environment-friendly products because of pesticides detected more than their 10% MRLs in organic and pesticide-free agricultural products.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.45-53
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• 1999

Red sorrel (Rumex acetosella L.) is a troublesome perennial weed in the alpine grasslands of Kangwon Province of Korea. A number of soil- and foliar-applied herbicides were evaluated for their efficacy of red sorrel control. In greenhouse experiments, no soil-applied herbicides, such as pendimethalin, simazine, alachlor, metolachlor, ethalfluralin controlled red sorrel, however, foliar-applied herbicides, such as glufosinate, paraquat, glyphosate, glyphosate + 2,4-D, dicamba, mecoprop, 2,4-D, bentazone controlled more than 60% of red sorrel 2 weeks after treatments. When dicamba and 2,4-D were applied to red sorrel in different growth stages, the auxin-type of herbicides cold control red sorrel regardless of growth stage. This result implies that the auxin-type herbicides can be applied between early May (early growth stage) and mid lune (before fruit maturation) at Kangwon alpine grasslands. In a field experiment, glufosinate at 1.0 kg a.i, $ha^{-1}$, glyphosate at 3.28 kg a.i. $ha^{-1}$, dicamba at 0.96 kg a.i. $ha^{-1}$, and mecoprop at 150 kg a.i. $ha^{-1}$ controlled more than 80% of red sorrel 4 weeks for treatment, suggesting such herbicides could be applied for red sorrel control at Kangwon alpine grasslands.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.211-218
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• 1985

To establish the weed control in transplanted bed of Pinus koraiensis and Larix leptolepis, alachlor, simazine, terbutryn, pendimethalin, oxyfluorfen and amitrol/2,4-D/methabenthiazuron (ustinex) were used by soil treatment and foliage application at 7days after transplantion of seedling. From the of soil treatment, grasses such as Dimeria ornithopoda, Alopecurus aequalis, Agropyron tsukushiense and Setaria verticillata were effectively controVed by 85 to 90% at the respective recommended rate of oxyfluorfen, alachlor and terbutryn. At the application rate of recommentation simazine, oxyfluorfen, pendimethalin and terbutryn respectively controlled 70 to 80% of broad-leaved weeds such as Erigeron annuus, Portulaca olearcea, Cerastium arvense, Capsella bursa-pastoris, Commelina commuis, Chenopodium hybridum and Stellaria alsine. Ustinex and oxyfluorfen were very effective for the control of perennials such as Artemisia princeps and Calystegia japonica. Initial sympton of phytotoxicity and decrease of growth in P. koreaiensis and L. leptolepis were not found by soil treatment and those in P. koraiensis was not shown by foliage application of all tested herbicides. But L. leptolepis foliage-applied with ustinex, oxyfluorfen, terbutryn and pendimethalin was great in early phytotoxicity and severe in growth inhibition.