• The Korean Journal of Pesticide Science
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• v.10 no.4
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• pp.359-366
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• 2006

The protective effect of kresoxim-methyl was investigated on 6 important plant diseases, and the vapour effect of it did on barley and cucumber powdery mildews, respectively. With 2.0 ${\mu}g\;mL^{-1}$ of kresoxim-methyl, its high activities against wheat leaf rust and barley powdery mildew were showed such as 92 and 100%, while activities were very low against rice sheath blight, tomato gray mold, and tomato late blight. In vapour phase control activity of kresoxim-methyl against barley powdery mildew was positively correlated with the applied concentrations, except for azoxystrobin and metominostrobin. With 200 ${\mu}g\;L^{-1}$, its control value was 71.9%. When 1000 ${\mu}g\;m^{-3}$ of kresoxim-methyl in vapour phase was applied on 4 plants of cucumber in a vinyl chamber, 51.1% of control value on kresoxim-methyl-treated cucumber was showed 7 days after the application.

• Applied Biological Chemistry
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• v.51 no.2
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• pp.108-113
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• 2008

Azoxystrobin applied by aqueous WP suspension 50 mg/l was slightly absorbed into cucumber leaf in the absence of activator surfactant 24 h after spraying, but was increased to 25.7% by adding polyoxyethylene monohexadecyl ether (12 moles of ethylene oxide, CE-12) 500 mg/l. Only 4.1% of kresoxim-methyl WDG 100 mg/l in the absence of surfactant was absorbed into cucumber leaf 24 h after spraying, but was increased to 58.0% by adding polyoxyethylene monooctadecyl ether (14 moles of ethylene oxide, SE-14) 1,000 mg/l. The effect of CE-12 500 mg/l on foliar uptake of kresoxim-methyl at 50 mg/l was twice bigger than on azoxystrobin. Fungicidal activity of azoxystrobin WP against cucumber powdery mildew was marginally increased by adding surfactants to facilitate foliar uptake of azoxystrobin, so that the further increase of azoxystrobin uptake into cucumber plant by the addition of adjuvant was not a practical mean for enhancing the formulation efficacy in view of fungicidal activity. It was not possible for kresoxim-methyl to assess the adjuvant effect on the fungicidal activity in a greenhouse trial due to the vapor effect of active ingredient.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.37-44
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• 2001

The biological effects of the iminoctadine tris (albesilate) and kresoxim-methyl for the protection of citrus postharvest diseases caused by penicillium spp. were assayed. In vitro tests, $EC_{50}$ values of iminoctadine tris(albesilate) were $0.01{\sim}0.02\;and\;0.01{\mu}g$ a.i./mL against mycelial growth of P. italicum and P. digitatum, respectively, but iminoctadine tris(albesilate) at $0.64{\mu}g$ a.i. /mL inhibited a little mycelial growth of unknown Penicillium sp. which produced another symptom different to blue and green mold caused by P. italicum and P. digitatum, respectively. And against germination and growth of germ tube of P. italicum and P. digitatum, $EC_{50}$ value of iminoctadine tris(albesilate) was $0.0013{\sim}0.0025{\mu}g$ a.i./mL. But spore germination of unknown Penicillium spp. was not nearly inhibited at $0.2{\mu}g$ a.i./mL. $EC_{50}$ values of kresoxim-methyl were $0.08{\sim}0.16$, 0.04 and $0.16{\mu}g$ a.i./mL against mycelial growth of P. italicum, P. digitatum and unknown Penicillium sp., respectively, and $0.04{\sim}0.08{\mu}g$ a.i./mL and $0.01{\sim}0.02{\mu}g$ a.i./mL against germination and growth of germ tube of P. italicum and unknown Penicillium sp., and P. digitatum, respectively. Iminoctadine tris(albesilate) and kresoxim-methyl were markedly effective to control the postharvest disease by 7 days spray prior to harvest. When the fruits were sprayed with iminoctadine-tris(albesilate) ($200{\mu}g$ a.i./mL) and kresoxim-methyl ($155{\mu}g$ a.i./mL) 7 days prior to harvest and subsequently stored for 90 days, the percentage of diseased fruit by Penicillium spp. was $3.6{\pm}1.8%$ in treatment of kresoxim-methyl and $5.9{\pm}1.8%$ in iminoctadine-tris(albesilate), respectively. On the other hand, tile percentage of diseased fruit was relatively high, $20.3{\pm}10.0%\;and\;19.5{\pm}9.6%$ in thiophanate-methyl ($700{\mu}g$ a.i./mL) and non-treatment, respectively. Maximum residue amount (ppm) among fruits (flesh and peel) assayed 0, 30, 60 and 90 days after storage was 0.45 and 0.10 ppm in treatment of kresoxim-methyl and iminoctadine, respectively.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.281-288
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• 2009

The strobilurin fungicides, azoxystrobin and kresoxim-methyl, were investigated to know the biological half-lives and dissipation patterns in Korean melon under plastic film house condition. Used pesticides for field application were 20% azoxystrobin of suspension concentrate and 47% kresoxim-methyl of water dispersible granule. Two pesticides were sprayed at recommended and double dose rate. Pesticide residues in Korean melon were analyzed until 14 days after application. The azoxystrobin was analyzed by HPLC equipped with UV detector after cleanup with florisil glass column. Initial residue concentrations of azoxystrobin in Korean melon at recommended and double dose rate were 0.09 mg/kg and 0.14 mg/kg, respectively. Those were less than 0.2 mg/kg maximum residue limit of Korean melon established by KFDA. The biological half-lives of azoxystrobin in Korean melon were 4.7 days at recommended dose rate and 7.8 days at double dose rate. Initial concentrations of kresoxim-methyl which was analyzed by GLC-ECD in Korean melon at recommended and double dose rate were 0.10 mg/kg and 0.23 mg/kg, respectively. Those were less than 1.0 mg/kg, MRL. The biological half-lives of kresoxim-methyl in Korean melon were 4.1 days at recommended dose rate and 4.8 days at double dose rate. The residue amounts of both pesticide was lower than MRL and biological half-lives were not so long. Because the weight of Korean melon under plastic film house condition was fast increased during cultivation.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.230-240
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• 2015

An IOM sampler equipped with glass fiber filter has been recently utilized instead of solid adsorbent, which was used to measure the inhalation exposure of agricultural operator to pesticides. The aim of this study is to validate the efficacy of an IOM sampler by measuring the trapping efficiency and breakthrough using kresoxim-methyl water-dispersible granule and fenthion emulsifiable concentrate. On LC-MS/ MS, minimum detection level was 12.5 pg and method limit of detection was 5.0 ng/mL. Good linearity ($R^2$ > 0.999) for matrix matched standards was obtained. Recoveries of pesticides from glass fiber filter were 102-109% (kresoxim-methyl) and 97-104% (fenthion) while those from XAD-2 resin were 94-98% (kresoxim methyl) and 93-100% (fenthion). Trapping efficiency test was performed with personal air pumps and IOM sampler (glass fiber filter) connected with solid adsorbent (XAD-2 resin) with two types of formulation (solid and liquid) which were diluted by standard rate and sprayed to IOM sampler. Those pesticides were trapped only in glass fiber filter without any breakthrough to solid adsorbent. After spiking of pesticides to glass fiber filter, breakthrough test was carried out with IOM sampler (glass fiber filter) which was connected with solid adsorbent. As a results, 87-101% of kresoxim-methyl and 96-105% of fenthion remained in spiked glass fiber filter, however, no pesticides were detected in second glass fiber filter and solid adsorbent. In conclusion, IOM sampler which equipped with glass fiber filter can be applied widely for pesticide inhalation exposure study since it has good trapping efficiency and adsorption capacity, regardless of the solid or liquid formulation.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.249-255
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• 2009

In order to calculate the processing and reduction factor between fresh and dry Welsh onion which was widely used as a dried agricultural ingredient of food in Korea. 7 pesticides such as pyridalyl, kresoxim-methyl, spinosad, flufenoxuron, difenoconazole, metconazole, and tebufenozide were tested. After 2 sites field trial conducted and measured water contents by drying at $60^{\circ}C$ and analyzed the pesticide residue. Water contents of fresh and dried Welsh onion are 89.2 and 10.2% respectively. Averages of processing factor showed 7.24 of pyridalyl, 2.85 of kresoxim-methyl, 7.43 of spinosad, 3.17 of flufenoxuron, 4.38 of difenoconazole, 2.40 of metconazole and 8.13 of tebufenozide into 2 field samples. Averages of Reduction factor showed 0.87 of pyridalyl, 0.35 of kresoxim-methyl, 0.88 of spinosad, 0.38 of flufenoxuron, 0.52 of difenoconazole, 0.29 of metconazole and 0.98 of tebufenozide. Residual amounts of pesticides in/on fresh Welsh onion reduced during drying process.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.35-40
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• 2005

Damping-off of summer spinach caused by Rhizoctonia solani AG-4 has become a very important disease. For the control of summer spinach damping-off, antifungal activity of thirteen fungicides (pencycuron, trifloxystrobin, pyraclostrobin, azoxystrobin, kresoxim-methyl, validamycin, fluazinam, Benlate-T, flutolanil, cyazofamid, hexaconazole, tebuconazole, prochloraz) were evaluated in vitro and in vivo. Pencycuron, pyraclostrobin, validamycin, fluazinam, Benlate-T, hexaconazole, tebuconazole, and flutolanil significantly suppressed the mycelial growth of the pathogenic fungus. However, trifloxystrobin, azoxystrobia kresoxim-methyl, cyazofamid, and prochloraz did not represent good inhibition on the growth of R. solani. When applied by soil drenching (2,000 mg/L), pencycuron, pyraclostrobin, validamycin, fluazinam, Benlate-T, and flutolanil provided spinach survival ratios of 97.8%, 84.4%, 93.3%, 95.6%, 91.1%, and 86.7%, respectively. Also when treated in seed at 2,000 ing/L, pencycuron and pyraclostrobin displayed survival ratios of more than 85.1%.

• Research in Plant Disease
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• v.11 no.1
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• pp.39-42
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• 2005

Powdery mildew, caused by Sphaerotheca aphanis var. aphanis, is an economically significant disease of strawberry in Korea. When powdery mildew is not controlled adequately, it often spreads rapidly through strawberry plants and damage is associated with reduced yields. Proper timing of fungicide applications is, therefore, essential for effective disease control. This study evaluated the efficacy by application schedule of fungicides before harvest stage for preventing powdery mildew in 2001-2003. The systemic fungicides, azoxystrobin, kresoxim-methyl, and cupper fungicide DBEDC were applied preventively during the first part of the cultivating season. Preventative applications of DBEDC by dipping treatment before transplanting and kresoxim-methyl by foliar spray before blooming stage were one of the most effective control schedule tested to prevent and manage this disease. This research demonstrated the significance of application time to control of powdery mildew, particularly provided elimination unnecessary sprays of agrochemicals and reduction costs for strawberry growers.

• The Plant Pathology Journal
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• v.39 no.4
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• pp.351-360
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• 2023

Citrus melanose, caused by Diaporthe citri, has been one of the serious diseases, and chemical fungicides were used for protection in many citrus orchards of Jeju Island. Establishing a disinfectant resistance management system and reducing pesticide usage would be important for contributing to safe agricultural production. In this study, monitoring of chemical resistance was performed with 40 representative D. citri isolates from many citrus orchards in Jeju Island. Four different fungicides, kresoxim-methyl, benomyl, fluazinam, and prochloraz manganese, with seven different concentrations were tested in vitro by growing the mycelium of the fungal isolates on the artificial medium potato dextrose agar. Among the 40 fungal isolates, 12 isolates were investigated as resistant to kresoxim-methyl which could not inhibit the mycelium growth to more than 50%. Especially isolate NEL21-2 was also resistant against benomyl, whose hyphae grew well even on the highest chemical concentration. However, any chemical resistance of fungal isolates was found against neither fluazinam nor prochloraz manganese. On the other hand, in vivo bio-testing of some resistant isolates was performed against both kresoxim-methyl and benomyl on young citrus leaves. Typical melanose symptoms developed on the citrus leaves pre-treated with both agrochemicals after inoculation with the resistant isolates. However, no or less symptoms were observed when the susceptible isolates were inoculated. Based on these results, it was suggested that some resistant isolates of D. citri occurred against both systemic fungicides, which may be valuable to build a strategy for protecting citrus disease.

• Korean Journal of Environmental Agriculture
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• v.26 no.4
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• pp.337-342
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• 2007

To obtain the data on the risk assessment of residue levels of organophosphorus and organochlorine pesticides in fresh ginseng and red ginseng extract, the residual pesticides in samples are surveyed with GC-NPD and GC-ECD for quantitative analysis and GC-MSD for qualitative analysis. The residual organophosphorus pesticides, such as diazinon, pyrimethanil, tolclofos-methyl, metalaxyl, diethofencarb, parathion, cyprodinil, tolylfluanid and kresoxim-methyl, are not detected in fresh ginseng from Punggi. The residual organophosphorus pesticides except tolclofos-methyl are not detected in fresh ginseng from Sangju. Average amount of tolclofos-methyl in fresh ginseng from Sangju are $0.054{\pm}0.008\;mg/kg$, representing $18{\pm}2%$ of MRL of 0.03 mg/kg on fresh ginseng in Korea. The residual organochlorine pesticides, such as BHC isomer, DDT isomer, aldrin, azoxystrobin, captan, cypermethrin, deltamethrin, dieldrin, difenoconazole, endosulfan-sulfate, endrin, fenhexamid, quintozene, ${\alpha}$-endosulfan and ${\beta}$-endosulfan, are not detected in fresh ginseng from Punggi and Sangju. The residual organophosphorus and organochlorine pesticides in red ginseng extract from Punggi and Sangju are not detected.