• Analytical Science and Technology
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• v.6 no.3
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• pp.283-288
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• 1993

The solvent extraction and clean up processes for the gas chromatographic determination of muarimol pesticide residues in apples were investigated and examined the changes of residual concentration with the passage of time. The extracted pesticide with methanol were partitioned with dichloromethane after adding sodium chloride solution. The separated solutions were concentrated and transfered to the alumina column for clean up, and eluated with 1-chlorobutane : methanol solution. As a results their recovering for 0.200 and 1.00ppm muarimol spiked on apples have shown 79~95%. Residual amounts of nuarimol in apple was 0.0830ppm when the fungicide was treated eight times until 3 days before its harvest. It seems to be safely used when nuarimol is treated six times until 7 days before harvest of apple.

• The Korean Journal of Pesticide Science
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• v.10 no.1
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• pp.36-42
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• 2006

For the effective control of pepper anthracnose, in vitro antifungal activities of 13 commercial fungicides were tested on spore germination, mycelial growth, and sporulation of Colletotrichum gloeosporioides, anthracnose fungus. Among them, captan, chlorothalonil, dithianon, fluazinam and folpet completely inhibited the spore germination of C. gloeosporioides at the concentration of 0.8 ${\mu}g/ml$. They were followed by mancozeb and propineb, showing more than 80% inhibition of spore germination at 20 ${\mu}g/ml$. The mycelial growth of C. gloeosporioides was strongly inhibited by fluazinam and nuarimol. Except for nuarimol, most of the fungicides represented more antifungal activity on the spore germination than the mycelial growth of C. gloeosporioides. Azoxystrobin and metominostrobin, Strobilurin fungicides, were only moderately active against the spore germination and the mycelial growth of C. gloeosporioides, but they were effective antisporulant against C. gloeosporioides. From these results, control of pepper anthracnose will have achieved by preventive spray of the commercial fungicides.

• Korean journal of applied entomology
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• v.43 no.1
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• pp.71-79
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• 2004

Toxicities of 42 pesticides (13 acaricides, 13 insecticides, 13 fungicides and 3 adjuvants) commonly used to control rose insect, mite, and disease pests were evaluated to the two-spotted spider mite, Tetranychus urticae egg and adult, and its predator Phytoseiulus persimilis egg, nymph and adult at the recommended concentration. The effect of density suppression of T urticae by predatory mite and pesticide mixture on the rose in the greenhouses was also investigated. Among 13 acaricides tested, acequinocyl, bifenazate, fenbutatin oxide and spirodiclofen showed much less toxicity to P. persimilis than to T urticae. Among insecticides, acetamiprid, imidacloprid, spinosad, thiamethoxam and acetamiprid＋etofenprox showed low toxicity to P. persimilis. and T ruticae. Among 13 fungicides, azoxystrobin, kresoxim-methyl, myclobutanil, nuarimol, triadimefon, triflumizole and oxadixyl＋mancozeb had a negligible effect on P. persimilis and T. urticae. Among three adjuvants, cover and siloxane expressed high toxicity, while spreader showed very low toxicity to P. Persimilis. In the greenhouses experiments, the density of T urticae before treatment was 65.3 mites per leaf. However, their density after release about 30 predatory mites per rose abruptly decreased from 3.8 mites at 11th day to zero mite at 20th day. During survey periods, four treatments of fungicides (kresoxim-methyl, myclobutanil, nuarimol, triflumizole) for the control of Sphaerotheca pannosa and one treatment of insecticide (spinosad) the control of Frankliniella occidentalis were applied, and these treatments had no the pesticides had no effect on the predatory mite density. It may be suggested from these results that four acaricides, five insecticides, seven fungicides, and one adjuvant could be incorporated into the integrated T. urticae management system with P. persimilis on rose cultivation.

• Korean journal of applied entomology
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• v.35 no.3
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• pp.232-237
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• 1996

Toxicity of 5 acaricides, 4 insecticides. and 6 fungicides to the twospotted spider mite, Tetranychus urticae Koch, and its predator Amblyseius womersleyi Schicha was assessed in a laboratory using a leaf disk bioassay. Dicofol was equally very toxic to aduly females of T. urticae and A. womersleyi, and caused 46% and 40% mortality of eggs of those two species, respectively. Adult females of A. womersleyi dipped in Abamectin solution showed low mortality(16.6%), while all T. urticae females died within 24 hours after dipping. Three ovicidal acaricides (Tetradifon, Clofentezine, and Hexythiazox) showed no mortality of predator eggs, but more than 90% mortality of T. urticae eggs. Four insecticides (Teflubenzuron, Triflumuron, Diflubenzuron, and Imidacloprid) and three fungicides (Propineb, Fenarimol, and Polyoxin-B captan) were non toxic to the A. womersleyi adult females. The other fungicides (Chlorothalonil, Nuarimol.Mancozeb, and Folpet) were a little toxic to adult females of the predator, showing$\leq$23.3% mortality, It may be suggested from these results that 4 insecticides, 4 acaricides, and 6 fungicides described could be incorporated into the integrated pest management system with A. womersleyi in apple orchard.

• Research in Plant Disease
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• v.8 no.4
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• pp.239-244
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• 2002

Among 34 isolates of Colletotrichum spp., 20 from red pepper and 14 from apple, only one isolate 2001-45 was identified as the isolate resistant to sterol biosynthesis inhibiting fungicides. EC$_{50}$ values of the isolate 2001-45 were 153.5, 42.7, 34.0, and 17.1 $\mu\textrm{g}$/ml for myclobutanil, tebuconazole, hexaconazole and nuarimol, respectively, The resistance factor of the isolate 2001-45 against the other isolate 2001-44 to 4 above fungicides was ranged from 17 to 57. However, EC$_{50}$ value of the 2001-45 for prochloraz was 0.07 $\mu\textrm{g}$/ml, which was lower than those of the 2001-44 and the isolate JC24. For the fitness test of the 2001-45, mycelial growth, sporulation on PDA and pathogenicity on fruits were investigated. No difference in mycelial growth was found between 2001-45 and 2001-44, but great difference in sporulation. No symptom was developed by 2001-45 even by wound inoculation of pepper fruit. Therefore, this study indicated that the isolate 2001-45 was inferior to the other isolates in the fitness, although the isolate 2001-45 was highly resistant to sterol biosynthesis inhibiting fungicides.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.422-428
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• 2005

In vivo antifungal activity of 44 fungicides consisting of 3 clubroot fungicides, 7 Oomycetes fungicides, 7 botriticides, 7 blasticides, 9 sterol biosynthesis inhibitors, and 11 broad spectrum fungicides were investigated against Plamodiophora brassicae, the causal agent of clubroot disease in Chinese cabbage. When fluazinam, flusulfamide and cyazofamid, commercial fungicide to control clubroot of Chinese cabbage in Korea, were applied to infested soil, club formations by P. brassicae were strongly inhibited at pot (35 $cm^2$) per 0.63 mg. Ethaboxam and cymoxanil, Oomycetes fungicides, completely controlled Chinese cabbage clubroot at 5 mg/pot, but cymoxanil represented sever phytotoxicity. Besides, dichlofluanid and procymidone of botriticides effectively controlled the development of Chinese cabbage clubroot at 2.5 mg/pot. Chlorothalonil, quintozene and trichlamide, broad spectrum fungicides, showed disease-control efficacy of 85%, 100% and 100% at 2.5 mg/pot, respectively. Most of sterol biosynthesis inhibitors displayed the strong antifungal activity against P. brassicae on cabbage seedlings and plant growth -retarding activity. From these results, 7 fungicides were selected and further tested in vivo antifungal activity against P. brassicae in glasshouse. Among them, ethaboxam showed the most antifungal activity against P. brassicae on cabbage seedlings, followed by fenarimol, procymidone, nuarimol and chlorothalonil.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.117-124
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• 2007

Esterase activity was observed after pesticides treatment in eggs of H. axyridis to select low toxicity pesticide. Egg esterases of H. axyridis were examined using an esterase substrate(${\alpha}$-naphthyl acetate). Three esterase isozymes were detected and the activities were inhibited by organophosphorus insecticide (Chlorpyrifos and Phenthoate), organochlorine insecticide(Methidation), triazole fungicide(Hexaconazole and Triflumizole), and pyrimidine fungicide(Nuarlmol). Fecundity and hatchability in adults and eggs of H. axyridis were examined on selected pesticides. Fecundity and hatchability were significantly reduced from H. axyridis adults and eggs treated with the pesticides and the fungicides showed strong inhibition of esterase isozymes activities. However, we also observed the pesticides and the fungicides showed low or non-inhibition of esterase isozymes activities affected on fecundity and hatchability in adults and eggs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.12
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• pp.1779-1784
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• 2009

Establishment of simultaneous analysis method and monitoring for individually analyzing residual eight ergosterol biosynthesis inhibitors, EBI (difenoconazole, diniconazole, fenarimol, fenbuconazole, hexaconazole, myclobutanil, nuarimol and paclobutrazol) pesticides in commercial agricultural products, were conducted. The simultaneous analysis method for the pesticides was established using a GC/MS/MS for EBI pesticides. Residual amount of those pesticides were investigated in 989 commercial agricultural products (fifteen kinds of cereal grains, vegetables, beans, nuts, fruits and mushrooms) from seven metropolitan cities and eight provinces. In EBI pesticides analysis, linearity of GC/MS/MS analysis was 0.9974-0.9992, and that of recoveries were 86-135% with relative standard deviations (RSD) <20%. The limit of quantification (LOQ) of the method ranged from 0.5 to 5.0 mg/kg for eight EBI pesticides. According to the monitoring of the EBI pesticides in commercial agricultural products, difenoconazole, fenarimol, hexaconazole showed various residual levels (total frequency of 8/989 detection, 0.8%). Paclobutrazole showed in excess levels of the MRLs (maximum residue limits) for pesticides in one chard sample by the Korea Food Code. As a result of exposure assessment on the detected 8 individual pesticides, all pesticides (difenoconazole, fenarimol, hexaconazole, paclobutrazole) were evaluated as safe level in comparison to toxicologically acceptable daily intake.

• Journal of agriculture & life science
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• v.45 no.5
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• pp.73-80
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• 2011

Fifty substances of pesticide were selected for analysis through the historical investigation of pesticides detected from environmental-friendly agricultural soil, and the environmental-friendly agricultural soils in Gyeongnam area were collected and then were accepted Anve (accelerated solvent extraction) and SPve (solid-phase extraction) as multiresidue extraction and clean up methods suitable to the soils. The pesticide residues were analyzed by using GC/vCD/NPD, HPLC/UV/FL, GC/MSD, or HPLC/MSD. 50 kinds of pesticides for the soils were an average of 95.5% from retrieval ratio of the 72 to 118% range, and the average of 3.0% for CV (%). Among 40 samples of soil, 20 components were detected from pesticide residues of 21 samples, and average amounts detected for these components were 0.035 for endosulfan, 0.043 for ethoprophos, 0.020 for chlorpyrifos, 0.023 for chlorfenapyr, 0.047 for flufenoxuron, 0.070 for fenvalerate, 0.266 for cypermethrin, 0.016 for lufenuron, 0.022 for bifenthrin, 0.025 for fenobucarb/BPMC, 0.043 for difenoconazole, 0.059 for fenarimol, 0.020 for kresoxim-methyl, 0.026 for tetraconazole, 0.039 for isoprothiolane, 0.017 for iprobenfos, 0.014 for nolrimol, 0.156 for fluquinconazole, 0.047 for tebuconazole, and 0.045 mg/kg for oxadiazon. Therefore it is infered that the establishment of pesticide residues limit for environmental-friendly agricultural soil is needed as soon as possible.

• The Korean Journal of Pesticide Science
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• v.7 no.3
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• pp.159-168
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• 2003

With microtiter plate, the assay method was developed for detecting the fungicidal activity of new compounds against spore germination, spore adhesion and mycelial growth of Colletotrichum sp. JC24 cal1Sing red pepper anthracnose. Also, the effects of some commercialized fungicides on fungal development like above mentioned were investigated by measuring the optical density of mycelia grown into wells of microtiter plate. For the standardization of assay method, some factors, such as the treatment of MTT and/or propanol, inodulum density and incubation period, affecting on mycelial optical density were investigated. For obtaining precise and consistent mycelial optical density, it was necessary the treatment of MTT for 12 hrs and propanol for 1 hr. inoculum density adjusted to $1\times10^5$ spores/mL and incubation period for 36 hrs at $25^{\circ}C$. For fungicidal activities, 6 protective fungicides, 6 ones inhibiting sterol biosynthesis, and one inhibiting respiration were used in this study. While mancozeb, chlorothalonil and dithianon among 6 protective fungicides inhibited strongly spore germination, adhesion, and mycelial growth at $6.25{\mu}g/mL$, propineb, iminoctadine and fluazinam inhibited intermediately spore germination and mycelial growth at $100{\mu}g/mL$. Washing above 3 fungicides with new PD broth, their activity against spore adhesion decreased. With hexaconazole, tebuconazole and myclobutanil, the tendency of the activity against fungal differentiation of the early infection stage was similar to the latter group of protective fungicides, showing the decrease of the inhibitory activity against spore adhesion by washing 2 hrs after incubation. However, kresoxim-methyl inhibited spore adhesion distinctly, depending on the applied concentrations. Based on these results, it might be able to assess the fungicidal activity of many compounds against spore germination, adhesion and mycelial growth by the use of microtiter plate in vitro. Using the assay developed in this report, it was possible to investigate the inhibitory activity of some commercialized fungicides, too.