• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.409-416
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• 2014

This study was conducted to reduce the using amount of chemical fungicides for the control of red-pepper powdery mildew. Effect of combined application of three microbial fungicides and six chemical fungicides for the control of red-pepper powdery mildew was examined in vitro, in pot assay and under field condition. One chemical fungicide (Azoxystrobin+Chlorothalonil) among six chemical fungicides significantly suppressed three microbial fungicides (Bacillus subtilis Y1336, Bacillus subtilis DBB1501, Bacillus subtilis QST-713) registered for the control of pepper powdery mildew in vitro. In the pot assay, two mixed application such as B. subtilis DBB1501+Trifloxystrobin, B. subtilis QST713+Trifloxystrobin among nine mixed applications of three microbial fungicides and three chemical fungicides showed the highest suppressive effect against red pepper powdery mildew. Also, suppressive effect of the mixed application of B. subtilis QST713 and Trifloxystrobin was similar to that of single application of three chemical fungicides(Myclobutanil, Trifloxystrobin, Hexaconazole). In the field test, when the microbial fungicides (B. subtilis DBB1501, B. subtilis QST713) and the chemical fungicide (Trifloxystrobin) for the control of powdery mildew of red pepper were mixed foliar sprayed four times at 7 day-intervals, the control values were in the range of 70.3% to 70.9%. On the other hand, when each of the chemical fungicide (Trifloxystrobin) was foliar sprayed four times at 7 day-intervals, the control value was 72.7%. Consequently, the mixed application of the microbial fungicides and chemical fungicides could be recommended as a one of control measures for reducing the using amount of chemical fungicides.

• The Korean Journal of Pesticide Science
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• v.15 no.2
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• pp.114-124
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• 2011

The characteristics of pesticide residues by multiresidue analysis method using GC, HPLC and GC-MSD were examined for 18,069 numbers of 91 kinds of vegetables in Seoul from 2007 to 2009. Detection rates of pesticide residues were 11.2% in 2007, 8.5% in 2008 and 12.0% in 2009, respectively, and the excess rates of Maximum Residue Limits (MRLs) showed a declining tendency as 4.6% in 2007, 2.8% in 2008 and 2.1% in 2009, respectively. The pesticides exceeding MRLs were 43 ingredients in 2007, 30 ingredients in 2008 and 36 ingredients in 2009, respectively. The frequencies of pesticides exceeding MRLs were 71 of azoxystrobin in 2007, 29 of procymidone in 2008, 24 of endosulfan in 2009, respectively. The excess rate of mustard green for MRLs in comparison with sample numbers was the highest among vegetables analyzed more than 10 cases each year. As a result of comparing annually pesticide residues about pesticide ingredients showed high frequency rates for pesticide detection, there was a statistical significance for the detection quantities of diazinon, endosulfan, paclobutrazol and procymidone.

• Research in Plant Disease
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• v.14 no.1
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• pp.51-56
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• 2008

Powdery mildew of lettuce that is a newly reported disease became a threat to organic cultivation of lettuce in Korea since the disease caused by Podosphaera fusca resulted in a half of yield loss in heavily infected fields. To improve micro-environmental conditions around lettuce, ACF (air-circulation fan) was installed on inside roof of plastic house at 6 m intervals. The ACF increased 57% of lettuce yield and reduced 71.4% of lettuce seedling death. COY (cooking oil and yolk mixture) consisted of cooking oil 0.3% and egg yolk 0.08% reduced lettuce seedling death from 89.3% to 92.9% under the greenhouse. Seven-day interval spray of COY resulted in high control values of powdery mildew of lettuce ranging from 89.6% to 96.3%, which was comparable to a fungicide, Azoxystrobin. Lettuce yield was increased about two times compared to a non-treated conventional cultivation. Qualities of lettuce such as hardness and chlorophyll content were also improved by COY and ACF combination. Effect of COY on control of the disease was improved when $CaCO_3$ or $SiO_2$ 1,000 ppm was supplemented. Results indicated that the COY made of cooking oil such as canola emulsified with yolk was highly effective on control of powdery mildew of lettuce and suitable for organic agriculture, especially when combined with ACF.

• Journal of Food Hygiene and Safety
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• v.39 no.3
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• pp.239-249
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• 2024

In this study, we investigated the concentrations of pesticide residues in agricultural products marketed in northern Seoul and assessed their potential health risks. A total of 1,737 samples were collected using the QuEChERS method, followed by LC-MS/MS and GC-MS/MS. Pesticide residues below the MRLs were detected in 560 samples of 72 items (32.2%), but 38 samples of 22 items had pesticide residues above the MRLs. Residual pesticides were detected in 53.8% of fruits, 33.0% of vegetables, 28.6% of herbs, 15.4% of beans, and 10.5% of rice samples. Most of the samples that exceeded the MRLs were vegetables, especially leafy, stalk, stem, and root vegetables; herbs and mushrooms also exceeded the permitted MRLs. Of the 105 pesticides investigated, dinotefuran, fluxametamide, chlorfenapyr, azoxystrobin, and carbendazim were the most frequently detected, whereas 23 pesticide residues, including terbufos, carbendazim, and fluxametamide, were detected above the MRL values. The hazard indices were calculated as 0.00003-1.31406%, which suggests that the investigated pesticide residues in the samples were within safe levels, but continuous monitoring of pesticides in agricultural products is needed to ensure the safety of consumers.

• The Korean Journal of Pesticide Science
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• v.20 no.3
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• pp.247-263
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• 2016

Safe animal feed is important for the health of animals, the environment and for the safety of foods of animal origin. Therefore, the aims of this study were: 1) to validate simultaneous analytical method and 2) to investigate the amount of pesticide residues in animal feed from Republic of Korea as a part of official control. A total of 126 samples were collected in 2015 and analyzed for 105 pesticides. According to pesticides monitoring result, no residue was found in 84.1% of the samples, whereas 15.9% of samples contained pesticide residues below the maximum residue limits (MRLs). Pirimiphos-methyl and cyproconazole were the two most frequently found pesticides. The results show that all commercial feed monitored in 2015 were safe under the Korean MRL and occurrence of pesticide residues in animal feed could not be considered serious threats to human and animal health. However, continuous monitoring with tighter regulation for pesticide residues in animal feed is recommended.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.356-360
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• 1999

Growth-inhibitory effects of citrus oils and agricultural fungicides, which were on the market, on several molds isolated from putrefied citrus fruits were investigated. When fungicidal activities of 11 kinds of synthetic agrochemicals against 6 species of molds, Alternaria alternata, Rhizopus sp., Botrytis cinerea, Monilia candida, Penicillium italicum and Penicillium digitatum, were investigated, agrochemicals containing mancozeb or fluazinam as an effective component had the broadest fungicidal spectrum. Agrochemicals containing iprodione, benomyl, azoxystrobin or thiophanate were less effective on the molds and those containing conazole derivative were intermediately effective. Resistance of the molds to the agrochemicals were species- and agrochemical-dependent. Among those molds tested, Penicillium italicum and Alternaria alternata showed relatively higher level of survival in the presence of synthetic fungicides. On the other hand, when the molds were exposed to citrus oils by direct contact, no cell could survive regardless of the species. The fungicidal activity of citrus oils was also confirmed by paper disk method and microscopic observation. These results suggested that citrus oils had broad killing activity against molds. Therefore, it would be necessary to design method for the application of citrus oils in order to improve post-harvest storage of citrus fruits.

• 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.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.166-172
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• 2011

BACKGROUND: Food Sanitary Act establishes Maximum Residue Limits (MRLs) of pesticides in food that are newly registered and used per each quarter, as stipulated by Agro-chemical Control Act. Current Food Code contains the MRLs for a total of 418 pesticides in 184 food types. METHODS AND RESULTS: National MRLs for pesticides have been established by based on scientific data of good agricultural practice, acceptable daily intake (ADI), food intake, average body weight and others. MRLs for pesticides are generally set under the principle that theoretical maximum daily intake (TMDI) are always below ADI. As results, 27 MRLs in agricultural products were newly proposed for 22 pesticides (fungicide: azoxystrobin, fludioxonil, fluquinconazole, flusilazole, iprovalicarb, kresoxim-methyl, mandipropamid, metconazole, pyraclostrobin, tebuconazole, triflumizole, etc., Insecticide: dinotefuran, flubendiamide, indoxacarb, cyhalothrin, spinetoram, thiacloprid, thiamethoxam, metaflumizone, etc., Acaricide(miticide): cyenopyrafen, lufenuron) in 2010. CONCLUSION(s): There is no intake concerns for establishment of pesticide MRLs on foods in this time. Because the ratio of theoretical maximum daily intake (TMDI) are set below that of ADI.

• Journal of Food Hygiene and Safety
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• v.33 no.5
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• pp.339-346
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• 2018

This study was conducted to monitor the current status of pesticide residues in a total of 297 agricultural products for raw juice from January 2017 to September 2017. Pesticide residues in samples were analyzed by multiresidue method for the determination of multiclass pesticide with an aim to detect 220 pesticides using GC/ECD, GC/NPD, TOF/MS, LC/PDA, LC/FLD, and LC/MS-MS. The analysis revealed the presence of nine pesticides in 14 samples. The detected pesticides were chlorpyrifos, cyflufenamid, chlorothalonil, pendimethalin, azoxystrobin, pyridalyl, imazalil, fludioxonil and procymidone. The kinds of detected crops were mandarin, carrot, apple, celery, chicory, orange and grape. Risk assessment evaluated human health exposure with the ratio of EDI (Estimated daily intake) to ADI (Acceptable daily intake) of pesticides detected and the range of %ADI (the ratio of EDI to ADI) values was 0.0011~6.7087% and safety level.

• Journal of Food Hygiene and Safety
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• v.37 no.4
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• pp.238-248
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• 2022

This study was conducted to evaluate the safety of 208 types of residue pesticides on 150 dried agricultural products in Ulsan. The pesticide residues were detected using GC-MS/MS, LC-MS/MS, GC/ECD, GC/NPD, and LC/PDA. The detection rate was 19.3% (29 of 150 samples), and 28 types of pesticides were detected. Two of the 29 pesticide residues exceeded the maximum residue limit (MRL). Difenoconazole was detected in Ulleungdo aster, and chlorothalonil and chlorpyrifos were detected in chili pepper leaves. In the vegetable group, the frequency of pesticide residues was found to be the highest in dried leafy vegetables, followed by dried fruiting vegetables other than cucurbit vegetables, and then dried stalk and stem vegetables. The pesticide types detected in the commercial dried agricultural products were fungicide (60%), insecticide (23.8%), and acaricide (16.3%). In the validation study, the values of limit of detection (LOD), limit of quantitation (LOQ), coefficient of determination (R²), and recovery rate were in the range of 0.0001-0.0409 mg/kg, 0.0003-0.1241 mg/kg, 0.994-0.999, and 81.58-116.79%, respectively. The ratio of estimated daily intake (EDI)/acceptable daily intake (ADI) was 0.00002-0.31395%.