• Research in Plant Disease
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• v.11 no.2
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• pp.185-192
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• 2005

In 1999 and 2002, 130 and 258 isolates of Colletotrichum spp. causing red pepper anthracnose were obtained from infected red pepper fruits, respectively. Their responses to 4 protective and 3 ergosterol biosynthesis-inhibiting(EBI) fungicides were investigated by observing their mycelial growth on PDA incorporated with different concentrations of each fungicide. The Colletotrichum isolates obtained in 1999 showed higher $EC_{50}$ values than those isolated in 2002 against three protective fungicides such as dithianon, chlorothalonil, and propineb, whereas the response was reversed toward other protective fungicide, iminoctadine. On the other hand, the isolates of year 1999 were more resistant against three EBI fungicides such as tebuconazole, hexaconazole, and prochloraz than those of year 2002; the $EC_{50}$ values of the former were 1.2-4.4 times higher than those of the latter, The responses of the Colletotrichum isolates toward protective and EBI fungicides were fluctuated according to regions, where the infected fruits were collected. On the other hand, the resis tance of Colletotrichum isolates to protective fungicides increased during monitoring from July to September, However, their responses towards EBI fungicides were not changed.

• Research in Plant Disease
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• v.11 no.2
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• pp.179-184
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• 2005

A previous study reported that the stem and root rot of paprika (Capsicum annum L. var, grossum) caused by Nectria haematococca became a threat to safe cultivation of the plant in the country. However, no strategies for control the disease have been suggested. In this study, fungicides registered for pepper were screened to evaluate their control effects on the disease. Among fungicides tested, prochloraz manganase complex com pletely suppressed mycelial growth of the pathogen at 10 ppm a.i. tebuconazole, benomyl, and carbendazim $\cdot$kasugamycin also effectively inhibited mycelial growth of the fungus. However, kresoxim-methyl and triflox ystrobin did not suppress mycelial growth but significantly suppressed conidial germination of the fungus. Azoxystrobin, benomyl, prochloraz, tebuconazol, and carbendazim$\cdot$ kasugamycin were also effective to retard conidial germination. In vivo tests, tebuconazole strongly inhibited the plant growth even at 16,000x (15.6 ppm a.i.), while others did not induce chemical injury at 4,000x or 8,000x when drenched into a rockwool cube. In a greenhouse test, prochloraz manganase complex at 125 ppm a.i. (4,000x) showed highest control value by $89.9\%$. Other fungicides thiophanate-methylthiram, axozystrobin, trifloxystrobin, and benomyl presented $60-80\%$ control value in the hydroponic cultivation system. However, application time and interval remained to be investigated for identify maximum residue limit.

• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.139-146
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• 2003

This study was conducted to investigate the effects on the over-growth inhibition of fruit vegetables (tomato, cucumber, and hot pepper) seedling by the treatment of triazole-typechemicals and to select the most effective chemicals for the over-growth inhibition, and to investigate suitabla concentration treatment and times of the newly selected chemical. The triazole-type chemicals inhibited stem height more, the more the concentration is increased in any crops. The diniconazole showed the highest dwarfing ration, and the tebuconazole and hexaconazole are also good for dwarfing ratio. The diniconazole decreased the plant height of cucumber, tomato, and hot pepper as the concentration is increased. In cucumber, thc dwarfing ratio was 30% in the 5 mg${\cdot}L^{-1}$ treatment, and was 60% in thc l00 mg${\cdot}L^{-1}$ treatment. In tomato and hot pepper, the dwarfing ratio was 30% in the 25 mg${\cdot}L^{-1}$ treatment in any times. In diniconazole treatment, the cucumber and tomato should have 5 mg${\cdot}L^{-1}$ at the lst growth stage and the hot pepper should have 5 mg${\cdot}L^{-1}$ at the 2nd growth stage to obtain good seedlings.

• 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.

• Research in Plant Disease
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• v.29 no.2
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• pp.145-157
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• 2023

Apple grower in the Cheongsong region, Korea has reported the increased loss of apple yield due to severe bitter rot incidence. We noticed that this indience is because the Colletotrichum population has developed resistance to commonly used fungicides. We isolated 39 Colletotrichum isolates from 13 orchards in Cheongsong, and all the isolated Colletotrichum species were identified as C. siamense or C. fructicola. These 39 strains were tested for mycelial growth and conidial germination against 12 fungicides. trifloxystrobin (30-55% in recommended concentrations) was shown lower inhibitory effect on mycelial growth. However, the inhibition of conidial germination was shown higher than mycelial growth (62-100%). Kresoxim-methyl was shown lower inhibitory effect on mycelial growth (29-55%). conidial germination inhibitory effect was shown 51% to 96%. dithianon was shown diversity response to inhibition of mycelial growth (43-100%). Tebuconazole was shown high inhibitory effect on mycelial growth (84-100%) and conidial germination inhibitory effect was shown to be 64 to 100%. metconazole has been found to display with high inhibitory effect on mycelial growth (79-100%) and conidial germination (70-80%). fluazinam was shown to possess high inhibitory effect on mycelial growth (87-100%) and conidial germination (94-100%). This study provides basic information for the effective management of apple bitter rot.

• Journal of Food Hygiene and Safety
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• v.39 no.2
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• pp.128-133
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• 2024

Using the freezing removal method, we investigated residual pesticides in 50 grape seed oils distributed in Gyeonggi Province, South Korea. The fat was mixed with acetonitrile and then frozen at ≤-20℃ for 24 h. Fats and oils were removed by separating those in solid state and the extract acetonitrile in liquid state. Ten residual pesticides were detected 161 times in 49 of 50 cases. The detected pesticides were boscalid, cyclufenamide, deltamethrin, difenoconazole, fluxapyroxad, fenpyrazamine, kresoxim-methyl, piperonyl butoxide, tebuconazole, and trifluoxysorbin. Boscalid, a fungicide, was most frequently detected (44 times), followed by fluxapiroxad (35 times). The detection range was 0.01-1.10 mg/kg, which was within the legal limit of residual pesticide for grapes. The recovery rate of the detected pesticides was 72.6-129.8% and the ratio of estimated daily intake/acceptable daily intake was calculated to determine the risk of the detected pesticides, which was <0.0028%. This indicated that the risk caused by pesticide residues in grape seed oil is at a safe level.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.229-236
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• 1998

The incidence of fungi and their possible contribution to low vigour were examined in a collection of ginseng (Panax quiquefolius) seed from Ontario. When examined after one winter of stratification in the field and storage at 4f for five months in the laboratory, the collection exhibited low vigour (plant stand 16.7% of seeding rate six weeks after seeding) and high incidence (94%) of discolored or soft seed. Fungi isolated (and incidence) from 1,304 endosperm halves recovered from surface-sterilized seed were, in order of abundance, Fusarium rostrum (22.2%), Chaetomium crispuum (14.3%), Funriud oxysporum (9.0%), Fusarium sdani (9.0%), iwmor sp. (8.4%), Alternaria sp. (8.1%), Zowieua lucotricha (7.8%), Cylindruarpn sp. (0.9%), Fusarium avenacmm (0.9%), and Vdudla iliata (0.4%). Most of these fungi, including known and potential pathogens of ginseng (species of Alerraria, Cylindrocarpon, Fusarium, and Trichodirma), were associated with both healthy and diseased seed. Application of Benlate (benomyl), Thiram (thiram), or UBI-2584 (tebuconazole) to seed caused slight to pronounced reduction in emergence and did not significantly affect plant stand six weeks after seeding. The study demonstrated the high level of infection by fungi, including known and potential pathogens of the cry, in an arbitrary collection of ginseng seed from commercial sources, and the phytotoxicity of the fungicides tested when applied to moist stratified seed. The lack of efficacy of the fungicides precluded determination of the contribution of seedborne fungi to low vigour of the seed.

• Journal of Ginseng Research
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• v.22 no.4
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• pp.223-228
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• 1998

As part of a study on the ability of fungicides to control disappearing root rot of ginseng (Panax quinquvdius) caused by Cylindruarpn destmtans, 15 fungicides were screened for toxicity to the fungus in vitro. Highly toxic fungicides were Benlate (benomyl), Thiram (thiram), and Orbit (propiconazole). EC5O values (mg a.i./L) were less than 1 and EC95 values were less than 10. Crown (carbathiin and thiabendazole), ASC-66835 (fluazinam), and UBI-2584 (tebuconazole) were moderately toxic, with EC5O values in the range 1-10 and EC95 values in the range 32-45. Weakly toxic fungicides (EC5O in the range 20-80, EC95 in the range 35-140) included UBI-2643 (thiabendazole), UBI-2565 (cyproconazole), and Vitaflo-280 (carbathiin and thiram). Anvil (hexaconazole), Vitaflo-250 (carbathiin), UBI-2383 (triadimenol), Daconil (chlorothalonil), CGA-173506 (fludioxonil), and CGA-169374 (difeno- conazole) were considered nontoxic to C. destmtan (EC5O 1.29->600, EC95>500). Relations between proportional inhibition of growth and concentration of fungicide were linear on arithmetic plots (Benlate, UBI-2643, UBI-2565, Vitaflo-280) or logarithmic plots (all other fungicides). Based on toxicity in vitro and formulation, it is recommended that Benlate, Orbit, and ASC-66835 be tested as soil drenches, and Benlate, Thiram, UBI-2584, and Crown be tested as seed treatments for controlling disappearing root rot.

• Journal of Haehwa Medicine
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• v.22 no.1
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• pp.129-143
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• 2013

This study was conducted to investigate the residue amount of pesticide on the 41 medicinal herbs in Daejeon area. This study was carried out to monitor the current status of pesticide residues in commercial medicinal herbs for sale of food use in 2012. It was performed using GC/ECD, GC/NPD, HPLC to analyze pesticides residues. Residues of 283 pesticides were analyzed by a simultaneous multiresidue method in 41 medicinal herbs being on sale in Daejeon. The medicinal herbs detected pesticides in 10 of 41 cases, showed a detection rate of 24.39%. The medicinal herbs which exceed the maximum residue limit were five cases as Cnidii Rhizoma, Osterici Radix, Artemisiae Capillaris Herba, Zizyphi Fructus and Alismatis Rhizoma. And pesticide residue of Cnidii Rhizoma and Alismatis Rhizoma exceeds the limit standard presented in only medicine use of KFDA. The residual pesticides which had the high detection rate were Chlopyrifos, Tebuconazole and Endosulfan in the detection of medicinal herbs. For further research, standards of Pesticide Residues in medicinal herbs should be added and more research of pesticide residues in medicinal herbs required. And standards of pesticide residues in medicinal herbs should be applied equally as medicines and food.

• The Plant Pathology Journal
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• v.32 no.6
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• pp.570-574
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• 2016

Botrytis cinerea is a necrotrophic pathogen causing a major problem in the export and post-harvest of strawberries. Inappropriate use of fungicides leads to resistance among fungal pathogens. Therefore, it is necessary to evaluate the sensitivity of B. cinerea to various classes of fungicide and to determine the effectiveness of different concentrations of commonly used fungicides. We thus evaluated the effectiveness of six classes of fungicide in inhibiting the growth and development of this pathogen, namely, fludioxonil, iprodione, pyrimethanil, tebuconazole, fenpyrazamine, and boscalid. Fludioxonil was the most effective ($EC_{50}$ < $0.1{\mu}g/ml$), and pyrimethanil was the least effective ($EC_{50}=50{\mu}g/ml$), at inhibiting the mycelial growth of B. cinerea. Fenpyrazamine and pyrimethanil showed relatively low effectiveness in inhibiting the germination and conidial production of B. cinerea. Our results are useful for the management of B. cinerea and as a basis for monitoring the sensitivity of B. cinerea strains to fungicides.