• Korean Journal of Soil Science and Fertilizer
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• v.39 no.5
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• pp.280-284
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• 2006

The toxic effects of 14 commercially available fungicides on the earthworm, Eisenia fetida (Savigny), were evaluated using surface sprayed soil, immersion and contact filter tests. At recommended dose, the earthworm mortality is 4% on mancozeb, carbendazim, propineb and captan in the surface sprayed soil test, 4% on mancozeb, 6% on propineb and 10% on captan in the immersion test, and no effect on all used chemicals in contact filter test.

• Korean journal of applied entomology
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• v.45 no.2 s.143
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• pp.179-188
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• 2006

The toxicities of 37 commercial pesticides for citrus pests were evaluated to H, fallacis. Eight fungicides (difenoconazole, imibenconazole, azoxystrobin, dithianon, fluazinam, procymidon, streptomycin, tribasic copper sulfate), three insecticides (dichlovos, imidacloprid, thiamethoxam) and four acaricides (milbemectin, tetradifon, dicofol, spirodiclofen) had lower effect to the hatchability of eggs N. fallacis. Six fungicides (propineb, difenoconazole, imibenconazole, azoxystrobin, dithianon, procymidon) and three acaricides (bifenazate, tetradifon, spirodiclofen) showed lower contact toxicity to adult N. fallacis. The secondary toxicity of 26 pesticides to N. fallacis adult were evaluated. Two fungicides (fluazinam, streptomycin) and 3 acaricides (machine oil, cyhexatin, halfenprox) showed low toxicity when the prey (eggs of spider mite) was treated with pesticides.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.203-208
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• 2009

In order to elucidate the effect of spreader-stickers on the rainfastness of dithianon and chlorothalonil wettable powders, and to estimate the possibility of suggesting good new formulations, the fungicide residues on the leaf surface of hot pepper was assessed and compared after the drop-wise applications of fungicide suspensions containing spreader-sticker on leaf surface followed by artificial raining. Three commercial spreader-stickers, which were Cover, Reitron and Silwet, not only made the rainfastness of dithianon wettable powders worse on hot pepper leaf, but increasing their concentrations also accelerated it further. On the other hand, to chlorothalonil wettable powder, Reitron showed the 3-fold improvement of rainfastness. But, for the rest, there was no improvement as well. The effect of N-octylpyrrolidone (NOP) on rainfastness of both fungicides was excellent. Soybean oil formulations containing leaf-penetrable nonionic surfactant, which was either polyoxyethylene monotridecyl ether or polyoxyethylene monolauryl ether, improved dithianon rainfastness, but the ones containing conventional emulsifiers did not.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.161-167
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• 2014

This study was conducted to investigate the resistance of Botrytis cinerea to azoxystrobin, which belongs to strobilurin fungicides. The sensitivity of B. cinerea isolates, which were collected from infected pepper, strawberry, cucumber and tomato by a single spore isolation, to the fungicide was tested through a agar dilution method on PDA amended with fungicides and $100{\mu}g\;mL^{-1}$ of salicylhydroxamic acid (SHAM). All isolates of B. cinerea tested in this study were classified as a sensitive and a resistant group by $1.0{\mu}g\;mL^{-1}$ of $EC_{50}$ value to azoxystrobin. While the sensitive isolates accounted for 46.5% of B. cinerea population, the resistant ones did for 53.5%. According to the regions isolating B. cinerea, the highest isolation frequency was showed as 81.1% in Chungnam among the all. Among 4 host plants as pepper, strawberry, cucumber and tomato, the highest isolation frequency was obtained in strawberry, while the lowest was done in pepper. The isolate resistant to azoxystrobin showed the cross resistance to other fungicides included into strobilurins as kresoxim-methyl and trifloxystrobin. In spite of an excellent efficacy of strobilurins, it should be taken care to use them in the field, because of the high risk in the fields.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.69-75
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• 2006

For the development of new agrochemical fungicide 3-amino-2-phenylimino-1,3-thiazolines 2 were designed through the molecular modification based on isostere concept of 3-methyl-2-phenylimino-1,3-thiazolines 1 which showed antifungal activity against rice blast. All the compounds 2 were fit Lipinski rule and they had higher solubility in water than that of 1 by virtual calculation. We constructed 195 kinds of focused library of 3-amino-2-phenylimino-1,3-thiazolines through 6H-[1,3,4]thiadiazines (195 compounds) which synthesized from the reaction of thiourea 4 with $\gamma$-chloroacetoacetanilides 5.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.189-197
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• 2004

Alpine and sloped-land in Gangwondo, Korea is the most important land type for cultivation of Chinese cabbage. However, farmers in these regions have major problems with insect pests, weeds and disease. Over use or inappropriate use of agrochemicals occurs frequently. No intensive study of pesticide contamination in this area has been done. The work presented in this paper addresses this deficiency. We measured pesticide residues within soil and water samples using multiresidue analysis. Samples were collected bimonthly from April to October, 2002 at three sites with to sampling spots. At the three sites, Pyeongchang, Jeongseon and Taebaeck, pesticides most frequently detected (>30% of samples) in soil samples were endosulfan, fluazinam, diniconazole, alachlor, prothiofos and dimethomorph. The amount of pesticide residues in the soils was ranged from 0.004 to $0.412\;mg\;kg^{-1}$ in these samples. Non-registered pesticides were also detected in these samples, indicating illegal use of pesticides. No pesticide were detected in the water samples collected from those sites. The results showed that pesticide residues might be dependant on physiochemical properties of pesticides, application history and soil properties. This study provides basic data for appropriate pesticide use on alpine and sloped-land in Korea.

• The Korean Journal of Pesticide Science
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• v.3 no.3
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• pp.37-44
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• 1999

Two sulphamide (dichlofluanid and tolylfluanid) and three dicarboximide fungicides (iprodione, vinclozolin, procymidone) were used to investigate the correlation between in vitro antifungal activities and in vivo disease controlling activities against Botrytis cinerea, a causal agent of tomato gray mold and to develop efficient in vitro assays. They controlled effectively the development of tomato gray mold disease in vivo and their controlling activities were similar one another. However, several in vitro assays revealed that their in vitro antifungal activities were quite different between sulphamide and dicarboximide fungicides; the formers showed stronger inhibition activities for spore germination than the latters, whereas the formers inhibited mycelial growth less severely than the latters. The results indicate that the fungicides having different modes of action can show different in vitro antifungal activities according to in vitro assays, even if they have similar in vivo disease controlling activities. On the other hand, two rapid and efficient in vitro assays named Microtiter plate methods I (MPM I) and II (MPM II) were developed for the evaluation of fungicides for inhibitory activities against spore germination and mycelial growth of B. cinerea, respectively. The antifungal activities of five fungicides of two chemical groups in MPM I and II were correlated with the inhibitory activities against spore germination and mycelial growth using solid media, respectively.

• 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.12 no.2
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• pp.177-183
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• 2008

For the development of integrated pest management system by harmonizing biological and chemical control, some experiments were carried out to select low toxic pesticides against natural enemies. Leaf dipping method, body dipping method, and diet treatment method were used for the toxicity evaluation against Microplites mediator adults. We tested 49 different pesticides (34 insecticides, 11 fungicides, 4 herbicides) at recommending concentration commonly used to control insect pests, disease and up-land weeds in chinese cabbage field. 16 insecticides, 11 fungicides, and 4 herbicides were shown to be low toxic to Microplites mediator adults in the treatment of body dipping.

• Korean Journal of Environment and Ecology
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• v.33 no.2
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• pp.178-186
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• 2019

This study used the probit analysis to evaluate the toxicity of three chemicals - benomyl (Germicide), carbofuran (insecticide), and thiobencarb (herbicide) - with the FETAX (Frog Embryo Teratogenesis Assay-Xenopus) protocol using the incubated embryos of tree frog, Hyla japonica. The results showed that the larval body length decreased while the mortality and malformation rates increased as the concentrations of benomyl, carbofuran, and thiobencarb increased. The teratogenic concentration ($EC_{50}$) of benomyl, carbofuran, and thiobencarb were 1.00, 0.58, 4.75 mg/L, respectively, indicating that the malformation of larvae was the most sensitive to carbofuran. The embryo lethal concentration ($LC_{50}$) was 7.04, 28.71, and 16.12mg/L, respectively, indicating that benomyl showed the lowest embryo lethal concentration. The teratogenic index (TI) was 7.04 in Benomyl, 49.50 in Carbofuran, and 3.39 in Thiobencarb, indicating that the TI values were above 1.5, which is the criterion of teratogenicity, for all three chemicals. All three pesticides examined by this study were considered to be the most teratogenic substances, and the carbofuran was the most potent teratogen.