• Journal of Environmental Analysis, Health and Toxicology
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• v.21 no.4
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• pp.304-315
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• 2018

Located in Gimhae, Hwapo is the biggest riverine wetland in the province of Gyeongsangsam-do, Korea, and is a major habitat for various species. However, it is suspected that various pollutants enter the wetlands from agricultural and industrial areas. This study identifies major organic pollutants in this wetland and their sources using high performance liquid chromatography-high resolution mass spectrometry during one summer season. Forty-five substances were selected for quantitative analysis using target screening, and other non-selected compounds were screened using suspect and non-target screening methods. The results were that 21 and 17 targeted substances were detected in July and August, respectively. Major pollutants in July and August were oxadiazon (July: 17-220 ng/L, August: 66-460 ng/L), carbendazim (July: 10-110 ng/L, August: 64-520 ng/L), caffeine (July: 33-1,100 ng/L, August: 56-580 ng/L), and niflumic acid (July: 23-75 ng/L, August: 42-290 ng/L). Sampling sites S4 in July and S2 in August were the major inflow points. Ten substances (tricyclazole, hexaconazole, diuron, fexofenadine, irbesartan, simetryn, cimetidine, valsartan, tebuconazole, and benzotriazole) and four metabolites (valsartan acid, azoxystrobin acid, TEB_M324c, and 2-aminobenzimidazole) were tentatively identified through suspect and non-target screening, respectively.

• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.55-66
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• 1999

Effect of an antagonistic bacterium AF-2001, Pseudomonas cepacia, on control of turfgrass diseases as brown patch, Pythium blight, dollar spot, and large patch were evaluated in vitro and in vivo. Results obtained in this study are summarized as follows. 1. Pseudomonas cepacia AF-2001 showed antagonism against to the pathogens causing brown patch, Pythium blighe, dollar spot and large patch. Especially, the biological agent showed strong antagonistic effect on the causal pathogens of brown patch, dollar spot, and anthracnose, but weak on Pythium blight 2. Populotion density of P. cepacia AR-2001 decreased ra;idly in turfgrass soils. Initial population of the agent was 2.4$\times$107 cfu/g soil, however, decreased to 1.4$\times$103, 6$\times$102 and 0 cfu/g soil on 10, 20, and 30 days after application, respectively. 3. Under the controlled controlled conditions of $27^{\circ}C$ and 95% RH, P. cepacia AR-2001 showed 100% control efficacy on brown patch either by pre-treatment or post-treatment of infection. However, Pythium blight was controlled about 94% by pre-treatment and only 29% by post-treatment 4. In field trials, P. cepacia AF-2001 did not suppress large patch and the control efficacy on other turfgrass diseases was lower than agro-chemicals such as tebuconazole and metalaxyl. Control efficacy of brown patch, Pythium and dollar spot by the biological agent was 57.4%, 40.4%, 61.5~87%, respectively. 5. Growth, color and texture of creeping bentgrass were not differ significantly between AF-2001 treatment and untreated control.

• Research in Plant Disease
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• v.9 no.3
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• pp.170-173
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• 2003

For the effective chemical control to minimize infection of storage pathogens on kiwifruit in the field, this study was conducted to screen alternative fungicides which could be substituted for the fungicides Benomyl WP and Thiophanate-methyl 제 registered for the control of postharvest fruit rats of kiwifruit in Korea. Among the 8 fungicides tested, Tebuconazole WP, Iprodione WP and Flusilazole WP showed higher inhibitory effects on themycelial growths of 3 major pathogens of postharvest fruit rots, Botryosphaeria dothidea, Diaporthe actinidiae and Botrytis cinerea on potato dextrose agar. They also showed control efficiencies as high as those of Benomyl WP and Thiophanate-methyl WP on postharvest fruit rots in the field. They might be good candidates for fungicieds for the control of postharvest fruit rots of kiwifruit.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.7-10
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• 2006

Anthracnose severely occurred on begonia (Begonia semperflorens Link.) nurseries in Gyeongju, Gyeongbuk in July, 2004. More than $80\%$ of begonia seedlings were diseased in the greenhouse surveyed and diseased leaves per plant were $12.1\%$ in average. Yellowish spots occurred on the leaves of begonia as initial symptoms, and they coalesced irregularly to form large brown pleomorphic lesions. Severely infected leaves were defoliated, resulting in abnormal growth of the entire plant. Colletotrichum sp. was repeatedly isolated from the diseased plants and was identified as Colletotrichum acutatum on the basis of the mycological characteristics on potato dextrose agar and RAPD analysis. Pathogenicity of the fungus was also confirmed by artificial inoculation on healthy plants. The optimum temperature for mycelial growth of C. acutatum was around $25^{\circ}C$. The fungus was sensitive to azoxystrobin, bitertanol, diethofencarb-carbendazim, difenoconazole and tebuconazole. This is the first report on the anthracnose of begonia caused by C. acutatum in Korea.

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.170-175
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• 2010

A total of 24 isolates of S. homoeocarpa were isolated from 16 golf courses in Korea. Chemical resistance of 24 isolates was determined by in vitro fungal growth on fungicide-amended media with thiophanatemethyl (Benzimidazole fungicide family), tebuconazole (demethylation inhibitor fungicide family: DMI), and iprodione (dicarboximide fungicide family). Results indicated that 83.3% of 24 isolates were resistant to iprodione, 62.5% resistant to thiophanate-methyl and 0% resistant to tebuconazale. The dual resistance of iprodione and thiophanate-methyl was 58.3.%. Occurrence rate of fungicide resistance of thiophanate-methyl and iprodione had no relation to turfgrass varieties and isolated locations of pathogen. In the filed test, procymidone, boscalid, and fluquinconazole+pyrimethanil effectively controlled the dollar spot of creeping bentgrass.

• Journal of the Korean Society of Food Culture
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• v.35 no.3
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• pp.285-293
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• 2020

This study was conducted to monitor the residual pesticides on red pepper powder produced in five regions, which are the major producers of red pepper in Korea, such as Ham-pyeong, An-dong, Yeong-yang, Yeong-gwang, and Cheongyang from 2015 to 2016. Residual pesticides were detected on all samples. Among the 286 pesticides tested, 58 pesticides were detected, with the most frequently detected being chlorfenapyr (93.7%). Twelve types of pesticides (chlorfenapyr, cypermethrin, chlorpyrifos, pyraclostrobin, cyhalothrin, tebuconazole, bifenthrin, deltamethrin, fenvalerate, lufenuron, azoxystrobin, and indoxacarb) were detected in all regions, and 14 types of pesticides were used only in certain regions. An analysis of the residual pesticides showed that none of the pesticides detected exceeded the MRL (Maximum Residue Limits). The Positive List System (PLS) requirements were applied to eight pesticides that had no set MRLs. 0.01 mg/kg (PLS requirements) was exceeded in 12 cases. A comparison of the estimated daily intake (EDI) of pesticides with the acceptable daily intake (ADI) to access their risk revealed %ADI values of 0.001-0.756. Carbofuran showed the highest (0.756%), but most pesticides were below 1%. The results show that residual pesticides in red pepper powder are at safe levels.

• Journal of Food Hygiene and Safety
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• v.24 no.4
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• pp.357-367
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• 2009

This study was carried out to investigate the current status of pesticide residues in 3,735 agricultural products in the northern area of Seoul from January to December in 2008. 3,735 samples, comprising 119 types of agricultrural products were assessed via a multiresidue method to detect 260 pesticides. Pesticide residues were detected in 19.7% (737 of 3,735 samples), and the rate at which the detected residues violated the maximum residue levels(MRLs) of the Korean Food Code was 3.2% (121 of 3,735 samples). Pesticide residues were detected in 72 spin-aches, 64 peppers, 45 sweet peppers, 40 perilla leaves, 38 korean cabbages and 37 dried agricultural products. The samples that violated the MRLs included 14 perilla leaves, 13 spinaches, 12 leek, 6 lettuces(leaf), 6 chards and 6 gyeojchaes. Procymidone, endosulfan, chlorfenapyr, cypermethrin, bifenthrin, tebuconazole and fenvalerate were all frequently observed. Procymidone, endosulfan, dimethomorph and diniconazole were the pesticides most frequently detected at levels that violated the Korean Food Code MRLs.

• Research in Plant Disease
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• v.7 no.2
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• pp.102-106
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• 2001

Currently the rice false smut caused by Ustilaginoidea virens (Cooke) Takah. has occurred widely in Korea. A survey on the disease incidence at rice fields in 8 inland provinces was carried out in 2000, showing that the disease occurred at 104 (7.5%) out of 1,152 rice fields examined, ranging from 1.5% to 13.7% in provincial average. It was found that the disease incidence was greatly affected by local weather conditions and rice cultivars. In case of the most susceptible cultivar Namchunbyeo, the disease incidence was only about 1.3% in Icheon, while it was over 20% in Namwon which had weather conditions of the shorter sunshine period (about 64%) and the higher amount of precipitation (about 130%) during the rice cultivation than Icheon. In Icheon, artificial inoculation of the pathogen failed to induce the disease, probably because of the weather conditions unfavorable to the disease development, which also suggests that its incidence may be dependent on the weather conditions. Susceptibility of rice cultivars to the disease varied greatly; eight resistant cultivars including Heukjinjubyeo were not damaged by the disease, but 2 cultivars including Geumnambyeo and Namchunbyeo were severely damaged, having more than 20% of the disease incidence. Among chemicals tested fur the control of the rice false smut tebuconazole WP showed the highest control efficacy of 83∼88% on cvs. Geumnambyeo and Namchunbyeo. Other chemicals such as azoxystrobin WP and ferimzone WP also effectively suppressed the disease development in the field trials.

• Horticultural Science & Technology
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• v.18 no.6
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• pp.823-826
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• 2000

This study was carried out to investigate the effect of plant growth retardants (daminozide, chlormequat, hexaconazole, uniconazole, paclobutrazole) and fungicides of triazole chemical (microbutanil, difenoconazole, terbuconazole, bitertanol) on the rooting of 'New Guinea' impatiens cuttings. In both 'Papete' and 'Anguilla', the formation of adventitious roots was promoted by all concentrations of chlormequat, hexaconazole, uniconazole, and paclobutrazole treated. More adventitious roots were formed with hexaconazole, uniconazole, and paclobutrazole than with chlormequat. Length of the longest root and rooting zone decreased at higher concentrations of chlormequat, hexaconazole, uniconazole, and paclobutrazole in 'Papete', while 'Anguilla' showed less responses. In contrast with plant growth retardants, the formation of adventitious roots was remarkably promoted by fungicides of triazole chemical such as microbutanil, difenoconazole, terbuconazole, and bitertanol in 'Pepete' and 'Martinique' impatiens, but was not in 'Pagopago'. However, length of the longest root and rooting zone showed more sensitive response in 'Martinique' and 'Pagopago' than in 'Pepete'. These results suggest that fungicides of triazole chemical can be effectively used for rooting promotion of impatiens cuttings.

• Mycobiology
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• v.35 no.2
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• pp.91-96
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• 2007

In the present study we first report in Korea the identification and characterization of Fusarium oxysporum isolated from rotten stems and roots of paprika (Capsicum annuum var. grossum) at Masan, Kyungsangnamdo in 2006. The fungal species produced white aerial mycelia accompanying with dark violet pigment on PDA. The optimal temperature and pH for the growth of the species was $25^{\circ}C$ and pH 7, respectively. Microscopic observation of one of isolates of the species shows that its conidiophores are unbranched and monophialides, its microconidia have oval-ellipsoidal shape with no septate and are of $3.0{\sim}11{\times}1.5{\sim}3.5\;{\mu}m$ sizes, its macroconidia are of $15{\sim}20{\times}2.0{\sim}3.5\;{\mu}m$ sizes and have slightly curved or slender shape with $2{\sim}3$ septate. The results of molecular analysis show that the ITS rDNA of F. oxysporum from paprika shares 100% sequence identity with that of known F. oxysporum isolates. The identified species proved it's pathogenicity by causing rotting symptom when it was inoculated on paprika fruits. The growth of F. oxysporum from paprika was suppressed on PDA by agrochemicals such as benomyl, tebuconazole and azoxystrobin. The identified species has the ability of producing extracelluar enzymes that degrade cellobiose and pectin.