• Korean Journal Plant Pathology
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• v.12 no.4
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• pp.415-421
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• 1996

대전, 공주, 논산, 부여와 김해 등에서 병든 딸기, 토마토, 오이에서 총 992균주의 잿빛곰팡이병균을 분리하여 이들 균주로부터 dichlofluanid 저항성 5균주, 감수성 5균주를 임의로 선발하였다. 분리된 균의 dichlofluanid 저항성을 조사한 결과 105균주(10.6%)가 저항성이었다. 저항성균 균사의 최소 억제 농도(minimum inhibitory concentration)는 100~500$\mu\textrm{g}$/ml 이상이었으나 감수성균은 10 $\mu\textrm{g}$/ml 미만이었다. Dichlofluanid 저항성의 안정성 조사를 위하여 35$^{\circ}C$고온 처리 및 계대 배양할 때 조사된 저항성 5균주 중 3균주는 저항성이 감소하거나 상실되었다. 저온 저장 및 온실에 장기 보관할 때는 조사된 저항성 균주 모두가 저항성이 감소하거나 완전히 상실되는 것으로 나타났다. 이러한 결과는 이 약제에 대한 저항성이 불안정하다는 것을 나타낸다. 오이에 감수성균 및 저항성균을 혼합 접종한 후 재분리할 때 시간이 지날수록 감수성균이 더 많이 분리되어 저항성균의 경합 능력이 감수성 균주에 비하여 열등하였다.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.427-438
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• 2023

Biocide dichlofluanid breaks down quickly and accumulates easily in sediment, potentially causing a persistent impact on various marine organisms. We analyzed the potential toxicity of dichlofluanid on major aquaculture species in Korea, Undaria pinnatifida. Female gametophytes of U. pinnatifida were exposed to dichlofluanid at concentrations of 0, 1, 2, 4, 8, 16, and 32 mg L^-1, and their survival and relative growth rate were analyzed. The no observed effect concentration(NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC₅₀) for female gametophyte survival were determined as 1, 2, and 10.82 (95% CI: 8.87-13.23) mg L^-1, respectively. The NOEC, LOEC, and median effective concentration (EC₅₀) for relative growth rate were 1, 2, and 6.58 (95% CI: 6.03-7.17) mg L^-1, respectively. Female gametophytes of U. pinnatifida were expected to experience toxic effects at concentrations above 2 mg L^-1 of dichlofluanid. These research findings are expected to serve as important reference data for evaluating the toxicity effects of U. pinnatifida in its early life stages when exposed to dichlofluanid.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.245-251
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• 1995

Nine hundred and ninety-two isolates of Botrytis cinerea were obtained from infected strawberries, tomatoes and cucumbers in Taejon, Gongju, Puyo, Nonsan and Kimhae in Korea. Six hundred forty-two (64.7%) isolates were benomyl resistant (BR), 245 (24.7%) were procymidone resistant (PR), and 105 (10.6%) were dichlofluanid resistant (DR). In the minimum inhibitory concentration (MIC) test, DR isolates showed mycelial growth on the PDA incorporated with 100 or 500 $\mu\textrm{g}$/ml of dichlofluanid, while dichlofluanid sensitive (DS) isolates did not grow on the PDA incorporated even with 10 $\mu\textrm{g}$/ml of dichlofluanid. Chemical concentrations for inhibition of spore germination were much lower than those for inhibition of mycelial growth. IC50 values, the effective concentrations for 50% inhibition of spore germination, for DR were 0.11~0.29 $\mu\textrm{g}$/ml, whereas they were 0.04~0.09 $\mu\textrm{g}$/ml for DS isolates. In comparison of fitness-related characteristics such as virulence, sclerotial formation, and sporulation, DR isolates were inferior to DS isolates. However, mycelial growth was little different between DR isolates and DS isolates.

• The Korean Journal of Pesticide Science
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• v.5 no.4
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• pp.50-56
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• 2001

In vitro experiments, several fungicides including prochloraz, tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 85% inhibition of mycelial growth of Pestalotiopsis theae (SP-3). Dichlofluanid and chlorothalonil inhibited mycelial growth at the rate of 10 and 33%, however benomyl did not inhibit mycelial growth of the fungus. Minimum inhibitory concentration(MICs) of iminictadine-triacetate on the mycelial growth of SP-3 isolate was $10{\mu}g/m{\ell}$, but that of P. theae $\underline{MAFF}$ 752002 and P. longiseta $\underline{MAFF}$ 752001 was $1{\mu}g/m{\ell}$. MIC of benomyl, chlorothalonil, dichlorofluanid was $1,000{\mu}g/m{\ell}$, and that of fludioxonil, fluazinam, tebuconazole was $10{\mu}g/m{\ell}$. Conidial germination was inhibited more than 80% in tile medium which contained $1{\mu}g/m{\ell}$ of prochloraz, tebuconazole, fluazinam, fludioxonil, and minoctadine-triacetate. Control values of benomyl, chlorothalonil and dichlofluanid were 40, 60 and 30%, respectively. The controlling effect of iminoctadine-triacetate ($10{\mu}g/m{\ell}$) aganist P. theae (SP-3) in leaf disc test was more than 93%, but benomyl and dichlofluanid could not control leaf blight disease caused by P. theae (SP-3). Tebuconazole, fluazinam, fludioxonil, and iminoctadine-triacetate showed more than 94% of protective and curative effect of leaf blight of sweet persimmon, while, benomyl and dichlofluanid did not show any control effect of the disease.

• Research in Plant Disease
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• v.12 no.3
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• pp.249-253
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• 2006

Several fungicides such as polyoxine B, fludioxonil, tebuconazole, tebuconazole+dichlofluanid, and fenbuconazole were sprayed once a week on roses in greenhouse. Botrytis infection on stalks was reduced by 71-89% after regular fungicide spray. The reduction of conidial inoculum by these treatments is also observed. The rose petal infections were controlled significantly by these fungicides only 2 days after the application. The development of gray mold on rose flowers harvested just after spray of fludioxonil, tebuconazole and tebuconazole+dichlofluanid were reduced compared to untreated control. This beneficial effect was also shown in flowers artificially inoculated with B. cinerea conidia after harvest. Post-harvest treatments by spraying cut flowers with the fungicides such as iprodine plus thiram, tebuconazole+dichlofluanid and polyoxin D reduced disease incidence by 50-55%.

• Korean Journal of Environmental Agriculture
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• v.21 no.4
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• pp.231-236
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• 2002

We studied the residual patterns of two fungicides, dichlofluanid and iprodione, in cherry tomato greenhouse after applying with the recommended and double dose. Also, the degradation patterns during storage periods of up to ten days were compared between at room temperature (20$^{\circ}C$) and at cold temperature (4$^{\circ}C$). Removal rates of fungicides by washing with tap-water and detergent solution (0.1%, 0.2%) were measured. Half-lives of dichlofluanid and iprodione in greenhouse cherrytomato were 2.2$\sim$3.5 and 3.3$\sim$5.4 days, respectively. During the storage period, the residues were dissipated more slow. Removal rates were 62.8$\sim$80.3% by tap-water, 60.4$\sim$83.1% by 0.1% detergent solution, and 65.3$\sim$77.6% by 0.2% detergent solution. So, we can predict of terminal residues from cultivation period to marketing, storage and consuming.

• Journal of Food Hygiene and Safety
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• v.11 no.2
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• pp.89-97
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• 1996

This study was carried out to determine the pesticide residues in rice bran, crude rice bran oil and the oil of various stages of refining process. Each samples were analyzed for 41 pesticide residues by multiclass multiresidue methods with GC-ECD, NPD and identified by GC-MSD. Rice bran were detected cypermethrin, diazinon, dichlofluanid, and its level were ranged from 0.01~0.122 ppm. Crude rice bran oil were detected cypermethrin, diazinon, dichlofluanid, dimethoate, etrimfos, flucythrinate, and its level were ranged from 0.015~0.654 ppm Crude rice bran oil has the higher level of pesticide residues and more varieties of pesticides than rice bran. But pesticide residues in the crude rice bran oil was found to be almost removed then pigment was decolorized by absorption using active carbon and clealy removed by thermolysis for deodorization.

• Analytical Science and Technology
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• v.16 no.6
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• pp.438-442
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• 2003

The fungicides, used for grape growth and remained in the wine products from domestic and foreign countries such as vinclozolin, dichlofluanid, penconazole, procymidone were quantitatively analyzed after solid-phase extraction using a GC/MS-SIM method. The results obtained were as follows: for all the samples, the content of procymidone was in the range from 2.2 to $76.1{\mu}g/L$, recoveries 81.3-93.1 %, and standard deviation 1.4-3.4 %.

• Analytical Science and Technology
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• v.21 no.6
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• pp.459-473
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• 2008

Antifouling agents including tributyltin (TBT) compound and its derivatives have been used for many years, but the usage of TBT in Korea was legally restricted in 2003, due to its significant environmental impact. Following this, many new alternative antifouling agents have been used. In this experiment, four major antifouling agents were selectively analyzed to study their release in seawater and tidal flats on the Korean Peninsula. These new antifouling agents were extracted from the seawater and tidal flats using a liquid-liquid extraction method and microwave extraction, respectively. The measured concentrations of Irgarol 1051, Sea-Nine 211, Dichlofluanid and Chlorothalonil ranged from N.D.$-23.80ng/{\ell}$, N.D.$-15.30ng/{\ell}$, N.D.$-61.69ng/{\ell}$ and N.D.$-4.19ng/{\ell}$ in the seawater samples and from N.D.-159.45 ng/g, N.D.-476.57 ng/g, N.D.-59.79 ng/g and N.D.-21.27 ng/g in the tidal flat samples, respectively. Interestingly, these new antifouling agents were not detected in any area in the tidal flats at Pusan, whereas a certain amount of them was found in the seawater.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.429-436
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• 2005

As Sclerotinia sclerotiorum causing cucumber sclerotinia rot was the fastest in the mycelial growth at $25^{\circ}C$, its pathogenicity was strong at the same temperature among several temperatures. All the isolates of Sclerotinia sclerotiorum showed a strong pathogenicity against cucumber fruits, which was confirmed by a disk assay and a wound assay. A wound assay was superior to a disk assay to develop the assay system for assessing the fungicidal activity of several fungicides against Sclerotinia sclerotiorum. In a disk assay, it was very difficult to assess the fungicidal activity, because the pathogenicity of isolates used in the experiment was very strong. At 500 and $3.0{\mu}g/mL$, the activity of dichloflouanid and the mixture of carbendazim and diethofencarb against cucumber sclerotinia rot was 14.3 and 42.3%, respectively, by using a disk assay. However, at same concentration two fungicides showed the high controlling activity as 100 and 92.5%, through a wound assay in a laboratory. Also, the activity of two fungicides was good against cucumber sclerotinia rot in the greenhouse where cucumber plants were cultivated in the field, showing the control value as 91.1 and 82.9% at 100 and $825{\mu}g/mL$, respectively. All the isolates of Sclerotinia sclerotiorum from cucumber fruits sampled in the polyvinyl house were subjected to monitoring for the resistance to 7 fungicides. The $EC_{50}$ value of 7 fungicides was as follows: fenhexamid; $0.13{\mu}g/mL$, procymidon and iprodione; 0.18 and $0.24{\mu}g/mL$, carbendazim and the mixture of carbendazim and diethofencarb; 0.13과 $0.05{\mu}g/mL$, iminoctadine and dichlofluanid; 1.94 and $8.95{\mu}g/mL$. Ultimately it was not found that resistant isolates of Sclerotinia sclerotiorum were appeared in the field.