• Korean Journal of Weed Science
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• v.2 no.2
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• pp.129-140
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• 1982

Herbicides were classified by two-dimensional ordination analysis based on the weed flora which was not controlled by application of a particular herbicide. The number of herbicide group was varied depending upon the weed community type and the experiment site. The technique of the two-dimensional ordination analysis gave more comprehensive informations about selecting of herbicides for increasing the herbicidal efficacy, for increasing the weed spectrum and for reducing the herbicide cost by mixing of herbicides. The two-dimensional ordination analysis could be used not only herbicide classification and selecting effective herbicide or herbicide combination but also can be used for the evaluation of systematic application of herbicides.

• Korean journal of applied entomology
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• v.22 no.2 s.55
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• pp.147-159
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• 1983

In general, herbicides have been classified according to selectivity, mobility. time of application, methods of application, mode of action and chemical property and structure. However, there was no generally accepted classification system for practical use in the field. The primary processes affected by the majority of herbicides are the growth process through cell elongation and/or cell division, the photosynthetic process specifically the light reaction, the oxidative phosphorylation and the integrity of the membrane systems. The usual approach in the study of the mechanism by which herbicides kill or inhibit the growth of plants is to initially determine the morphological phototoxicity systems, The mechanism by which a herbicide kills a plant or suppresses its development is actually the resultant effect of primary and secondary(or side) effects. In most instances, the death of the plant is due to the secondary effects. To induce the desired response, a herbicide must be able to gain entry into the plants and once inside, to be transported within the plant to its site(s) of activity in concentrations great enough. Obstacles to the entry and movement of herbicides in plants are generally classified by leaf and soil obstacles, translocation obstacles and biochemical obstacles, and these obstacles are also strongly influenced by plant species and by environmental factors such as light, temperature, rainfall and relative humidity. And hence, in most instances, results obtained from laboratory or greenhous vary from those of field experiment. Author attempted to classify herbicides from the field experiment using the two-dimensional ordination analysis to obtain practical information for selecting effective herbicides or to choose effective herbicide combinations for increasing herbicidal efficacy or reducing the chemical cost. Based on this two-dimensional diagram, desired herbicides or combinations were selected and further investigated for the interaction effects whether these combinations are synergistic, additive or antagonistic. From the results, it was concluded that these new approach could possibly be give more comprehensive informations about effective use of herbicide than any other systems.

• Weed & Turfgrass Science
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• v.3 no.3
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• pp.165-173
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• 2014

This review study was conducted to recommend the effective use of herbicide mixtures in Korea. The herbicide ingredients by Herbicide Resistancce Action Committee (HRAC) was classified into 23 groupes according to the mode of action (acetyl CoA carboxylase inhibitors, acetolactate synthase, photosystem I and II inhibitors, protoporphyrinogen oxidase inhibitors, carotenoid biosynthesis inhibitors, enolpyruvyl shikimate-3-phosphate synthase inhibitors, glutamine synthetase inhibitors, dihydropteroate synthetase inhibitors, mitosis inhibitors, cellulose inhibitors, oxidative phosphorylation uncouplers, fatty acid and lipid biosynthesis inhibitors, synthetic auxins, auxin transport inhibitors and potential nucleic acid inhibitors or non-descript mode of action). The rice herbicide mixtures registered in Korea were classified based on the guideline of HRAC. Accordingly, such a classification system for resistance management can help to avoid continuous use of the herbicide having the same mode of action in the same field.

• The Korean Journal of Pesticide Science
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• v.15 no.4
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• pp.383-388
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• 2011

We investigated methiozolin acute toxicity using with Sprague-Dawley rats. The results of acute oral toxicity using rats showed $LD_{50}$ value of over 2,000 mg/kg bw for methiozolin. The calculate acute dermal $LD_{50}$ value of methiozolin was over 4,000 mg/kg. The skin irritation test showed moderately irritation and weak response of eye irritation test was observed in this experimental condition. According to these results, We concluded that methiozolin was Category IV in GHS chemical classification for acute toxicity. Future, we need more chronic toxicity test for safety.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.191-199
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• 2018

This study was to investigate the occurrence patterns of paddy weeds, their resistance levels to an ALS inhibiting herbicide, and to estimate the areas of resistance in these paddy fields. We used soil collected from 358 paddy fields of Jeonnam province in 2017. Based on their life cycles, weeds were 96% annuals and 4% perennial. Additionally, according to morphological classification, 59% were broad leaves, 28% were sedges and 13% were grasses. Different areas within Jeonnam province contained different numbers and occurrence rates of weed species. However, generally, we observed Lindernia dubia var. dubia, Monochoria vaginalis var. plantaginea, Ludwigia prostrata, L. procumbens, Cyperus difformis, Scirpus juncoides, Eleocharis Kuroguwai, Echinochloa oryzoides, and E. crus-galli var. echinata. We also observed seven weeds resistant to an ALS inhibiting herbicide. They were M. vaginalis, S. juncoides, C. difformis, L. dubia, Ludwigia prostrata, E. oryzoides, and E. crus-galli var. echinata. Although there were differences in the number and occurrence rate of resistant weed species to an ALS inhibiting herbicide among areas in Jeonnam province, the M. vaginalis, C. difformis, and S. juncoides occurred in 23 cities and counties in Jeonnam including Gwangju metropolitan city. Based on the rates (52%) of resistant occurrence to an ALS inhibiting herbicide in Jeonnam province, the area of weed resistant paddy fields was estimated to be 91,543 ha.

• Medical Lasers
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• v.9 no.1
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• pp.79-83
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• 2020

This paper reports a case of type 1 posterior glottic stenosis in a 60-year-old woman that was misdiagnosed as bronchial asthma. The patient was intubated at another hospital after ingesting herbicide and extubated seven days later. Although her voice changed, she had not received treatment at that time. She visited a local internal medicine clinic when her condition deteriorated to the point of dyspnea, but several months of treatment for bronchial asthma failed to improve her symptoms. Upon admission to the author's hospital, a laryngoscopic examination revealed a type 1 posterior glottic stenosis, which was removed surgically using a CO₂ laser.

• Korean Journal of Weed Science
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• v.10 no.3
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• pp.192-196
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• 1990

Eleven herbicides were treated in soybean fields of Dukso and Yeoncheon in Gyeonggi province. These herbicides were classified by two-dimensional ordination analysis based on important values of the weed flora which were obtained after application of herbicides. Weed community types were E. crus-galli(56%)-D. adscendens (14%) -C. album (10%)-P. oleracea (8%) and P. oleracea (58%)-E. crus-galli (29%) -A. mangostanus (5%) -D. adscendens (3%), respectively. From soybean field at Dukso, 11 weed community types or 11 herbicide groups were obtained. And at Yeoncheon, 9 weed community types or 9 herbicide groups were classified. At treated blocks with clomazone and bentazon, C. amuricus and E. crus-galli dominated respectively. And at treated blocks with quizalofop, haloxifop and alloxydium, P. oleracea dominated remarkably. The herbicides classification by the two-dimensional ordination analysis could be used more effectively to selecting herbicides for reciprocal and systematic weed control than by similarity analysis.

• Journal of Photoscience
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• v.8 no.2
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• pp.61-66
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• 2001

Using maize green- and white-leaf tissue, we have examined the effect of various chemicals on cytoplasmic leakage with respect to the light requirement or chloroplast targeting for their activities. Oxyfluorfen, oxadiazon, diuron, and paraquat, which are known as representative herbicides acting on plant chloroplasts, caused the electrolyte leakage only in the green tissues, whereas 2, 4-dinitrophenol, rose bengal (singlet oxygen producing chemical) and methyl-jasmoante (senscence-stimulating chemical) play a role both in green- and white-tissue. Benzoyl(a) pyrene, generating superoxide radical upon light illumination, functions only in white tissues. Tralkoxydim, metsulfuron-methyl and norflurazon showed no effect in two tested plant samples. In terms of light requirement in electrolyte leakage activity, diuron, oxyfluorfen, oxadiazon, rose bengal, and benzoyl(a) pyrene absolutely require the light for their functions, but other chemicals did not. based on these results, we could classify into four different response types according to whether chemicals require light or chlroplasts for their action. This classification is likely to be applied to simply and rapidly identify the requirement of light and chlroplasts for the actions of chemicals, thereby it makes easy to characterize many new herbicides that their action mechanisms are unclear, and to elucidate the mode of action of them.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.4
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• pp.541-549
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• 2019

Objectives: This study aims to examine patients who developed acute pesticide poisoning while spraying or using pesticide and presented to the emergency department in hospitals in Chungcheongnam-do Province. Based on the findings, this study will provide implications for safety and health management pertaining to the use of pesticides. Methods: Pesticide poisoning data collected by the Chungnam Center for Farmers' Safety and Health from 2014 to 2018 was cross-sectionally analyzed. A total of 331 patients with pesticide poisoning presented to one of hospitals and four of medical centers in the region(Dankuk University Hospital, Gongju and Hongsung, Cheongyang, Cheonan Medical Center). Seventeen of these patients (15 men and two women) developed poisoning while spraying pesticide. The patients' charts were reviewed to collect data on pesticide poisoning, namely currently working in farming-related occupation, means of transportation to the hospital, place of poisoning, symptoms of acute pesticide poisoning, treatment, pesticide used when poisoning occurred, and classification by technical ingredients. Results: Fifteen out of 17 patients who developed poisoning while spraying pesticide were men. Insecticide was used in 35.3% of the cases, and herbicide was used in 29.4% of the cases, which was different from cases of poisoning from ingestion poisoning. The major symptoms were vomiting (35.3%), nausea (29.4%), dizziness (29.4%), and headache (23.5%). A total 11 ingredients were identified in 12 patients, and the most common ingredient was glyphosate, which is an herbicide. Most patients showed a state of mild toxicity, but two patients showed a state of severe toxicity. These patients respectively used glyphosate and paraquat. Conclusions: Our findings can be useful for suggesting the need for a national healthcare system to manage occupational pesticide poisoning among farmers. Further, these findings can be used to increase the awareness of the risk of acute poisoning during pesticide spraying and suggest the need for a safety health education to increase farmers' awareness of pesticide poisoning.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.16-27
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• 1989

The six barnyardgrass [Echinochloa oryzicola (vasing.) Vasing.] and seventeen barnyardgrass [Echinochloa crus-gadli (L.) Beauv.] accessions, which were collected national widely in 1986 and selected two times through 1987. To study different growth response due to herbicide, pyrazolate, bifenox, quinclorac, the experiment was conducted with herbicide agar culture without nutrients, 1. Albinistic discoloration due to pyrazolate was more sensitive in E, crus-galli than E. oryzicola and among barnyardgrass accessions, Kumi, Ichon-A, Ichon-B, Boun-B and Kwangju-B were rather susceptible than Gyongju, Ansong, Boun-A, Jongju-A and Kwangju-A. 2. Twisting and growth retardation due to bifenox was less sensitive in E. oryzicola with less intra-specific variations than in E. crus-galli. Among E. crus-galli accessions, Boun-B, Ansong, Ichon-A, Ichon-B, Wonju and Kwangju-B were particulary susceptible, and Jinyang, Jongju-B, Jongju-A, Daejon, Kurye and Kwangju-A were tolerant as much as E. oryzicola. 3. Growth retardation and withering to dead due to quinclorac was more sensitive in E. oryzicola with less intra-specific variations than in E. crus-galli. Among accessions of E. curs-galli, Boun-A, Iri, Jongju-A, Jongju-B, Kwangju-A and Kwangju-B were rather similar suseptible to E, oryzicola than kimhae, Gyongju, Kumi, Wonju, Ichon-A, Ichon-B and Ansong. 4. Most accession of E. oryzicola was tolerant to both pyrazolate and bifenox, while susceptible to quinclorac. Among other accessions of E. crus-galli, Kurye, Kimhae, and Daejon were tolerant to all experimented herbicides, and Iri, Jongju-A, Jongju-B, and Kwangju-A were only tolerant to both pyrazolate and bifenox, while Kumi, Wonju, Ichon-A, Ichon-B, Boun-B and Kwangju-B were only tolerant to quinclorac.