• Weed & Turfgrass Science
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• v.5 no.3
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• pp.105-110
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• 2016

This paper provides the current status of weed science and prospects for the development of weed science based on the research trends presented at the 7th International Weed Science Conference in 2016. Approximately 520 researchers from 59 countries, including Korea, participated in the conference and presented 625 papers in nine research areas. Major research topics were herbicide resistance, weed ecology, weed management in agricultural and non-agricultural lands, herbicide spray technology, and non-chemical weed control. Studies on herbicide resistance presented more than 30% of all papers presented. Particularly, resistance to non-selective herbicides, such as glyphosate and glufosinate-ammonium, and non-target sites of resistance mechanisms were the main subjects of the herbicide resistance research area. Moreover, the conference focused on research concerning herbicide resistant weeds of staple crops of the world (corn, wheat, and rice). Arylex was introduced as a new compound which has a mode of herbicidal action similar to synthetic auxin. Three compounds being developed as HPPD inhibitors were studied for ways to reduce their toxicity and tested as mixed with safeners. Additionally, parasitic weeds, which are not native to Korea, are an expanding research subject in the world. Although 45 years have passed since the first report of herbicide resistance in 1970, herbicide resistance remains a serious problem in most intensive cropping systems of the world and will continue to be a major area of study in the future.

• Proceedings of the Korean Society of Crop Science Conference
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• 2006.04a
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• pp.168-169
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• 2006

• Journal of The Korean Society of Clinical Toxicology
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• v.17 no.2
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• pp.126-131
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• 2019

Purpose: Herbicide-related mortality has decreased since the complete ban of paraquat product sales in 2012, but there still have been other herbicides intoxications with relatively severe complications. Glyphosate and glufosinate herbicides are used widely, and considerable research has been conducted. Chlorophenoxy herbicide is another major herbicide that has shown poor outcomes and mortality without proper management, but research in this area is lacking. Therefore, this study compared the clinical features of chlorophenoxy herbicide with those of other herbicides. Methods: The medical records of patients exposed to herbicides at a tertiary academic university hospital in Korea from May 2014 to April 2019 were reviewed retrospectively. The demographic and clinical data of 135 patients were then analyzed to identify the recent herbicides intoxication trends after the paraquat sales ban, focusing mainly on chlorophenoxy herbicide poisoning. Results: Of the 135 patients, 13 patients (9.6%) had chlorophenoxy herbicide poisoning. No significant differences in all the variables were observed between the chlorophenoxy herbicide poisoning group and non-chlorophenoxy herbicides poisoning groups. Toxic symptoms after poisoning varied from nothing noticeable to confusion; none of the patients had severe complications after their treatments. Conclusion: Acute chlorophenoxy poisoning is relatively less severe, with lower mortality rates than glyphosate and glufosinate poisoning.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.392-395
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• 2006

The toxic effects of 9 commercially available herbicides on the earthworm, Eisenia fetida (Savigny) were evaluated with recommended dose, 2-fold and 4-fold dose using soil surface spray, immersion and contact filter tests in order to find out whether herbicides actually influence the life of earthworm in the soil or not. In the surface sprayed soil test, the earthworm mortality to nine herbicides were not significantly different from the comparison with the control regardless of level of dose. In the immersion test, the mortality of 4-fold dose was 34% in the napropamide and 64% in the alachlor. In contact filter test, the mortality appeared 80% in alachlor, 37% in napropamide, and 10% in triclopyr at 2-fold dose level and those of 4-fold dose were as follows: napropamide 96%, alachlor 80%, glyphosate 47%, triclopyr 37%, paraquatdichloride 37%; glufosinate ammonium 33%, pyributicarb 10%. As a result of these tests by three methods, the mortality of earthworm in terms of the recommended dose level was no observation about eight herbicides while the napropamide appeared 33% in contact filter test.

• Journal of The Korean Society of Clinical Toxicology
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• v.17 no.1
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• pp.7-13
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• 2019

Purpose: Owing to the increased agricultural use of the herbicide glufosinate ammonium (GLA), the incidence of GLA poisoning has recently increased. Therefore, we investigated the possible predictive factors associated with severe complications following GLA poisoning. Methods: A retrospective analysis of medical records was conducted based on 76 patients who had visited our regional emergency medical center with GLA poisoning from 2006 to 2017. Severe complications were defined as respiratory failure requiring intubation, systolic blood pressure less than 90 mmHg, Glasgow Coma Scale (GCS) less than 8, and presence of seizure. Results: Age, ingested amount and ingested amount per weight were significantly greater in the severe group (p<0.001). PSS grade 2 or higher was more common in the severe group (p<0.001), and In addition, the APACHE II score was significantly higher in the severe group (p<0.001), as were the SOFA scores (p=0.002). Serum ammonia levels were significantly higher in the severe group (p=0.007), while MDRD-GFR was smaller in the severe group (p=0.002). The spot urine protein levels were significantly higher in the severe group (p=0.005), as was the urine protein to creatinine ratio (p=0.001). Upon multivariate analysis, the amount ingested per weight and PSS grade 2 or higher were identified as significant predictors. Conclusion: Our study showed that MDRD-GFR was significantly lower in the severe group after GLA poisoning. PSS grade 2 or higher and ingested amount per weight may be useful to evaluate the severity of complications after GLA poisoning.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.121-133
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• 2023

The purpose of this study was to improve weed management systems under varying carbon dioxide concentrations and temperatures by evaluating the growth of Acalypha australis and observing the efficacy of four foliar and four soil herbicides, as well as measuring phytotoxicity in soybean crops treated with these herbicides. In both growth chamber and greenhouse conditions, plant height and shoot fresh weight of Acalypha australis increased as temperature increased. The variable to maximum fluorescence ratio (Fv/Fm), relative electron transport rate (ETR), plant height, leaf area, and shoot fresh weight of Acalypha australis were higher at carbon dioxide concentrations of 800 ppm than at 400 ppm. The efficacy of a foliar herbicide, glufosinate, on Acalypha australis was lower at 30℃ than at 20℃ and 25℃ in the growth chamber condition and was also lower at 29℃ than at 21℃ and 25℃ in greenhouse conditions. In contrast, mecoprop efficacy on Acalypha australis was lower at 20℃ and 25℃ than at 30℃ in growth chamber conditions and lower at 21℃ and 25℃ than at 29℃ in greenhouse conditions. Glyphosate efficacy was lower at 21℃ than at 25℃ and 29℃ under greenhouse conditions. With soil herbicides, metolachlor and ethalfluraline, efficacies were higher at relatively high temperatures under both growth chamber and greenhouse conditions. However, in the case of linuron, the difference in efficacy was not observed under varying temperatures in both growth chamber and greenhouse conditions. When ¼ of the recommended glyphosate rates were applied to Acalypha australis, efficacy was lower under 800 ppm carbon dioxide concentrations than under 400 ppm. In contrast, when ¼ of the recommended rate of bentazone was applied to Acalypha australis, efficacy was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. Despite application rates, glufosinate efficacy differed insignificantly under different carbon dioxide concentrations. When applied at ¼ of the recommended rate, the efficacy of ethalfuralin was higher under 800 ppm carbon dioxide concentrations than under 400 ppm. However, efficacies of other herbicides were not different despite varying carbon dioxide concentrations. Soybean phytotoxicity in crops treated with the recommended rate and twice the recommended rate of soil herbicides was not significantly different regardless of temperature and carbon dioxide concentrations. Overall, weed efficacy of some herbicides decreased in response to different temperatures and carbon dioxide concentrations. Therefore, new weed management methods are required to ensure high rates of weed control in conditions affected by climate change.

• Journal of Life Science
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• v.11 no.4
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• pp.316-320
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• 2001

Sonication tremendously improves the efficiency of Agrobacterium infection by introducing small and uniform fissures and channels throughout the targeted tissue. Using shoot tips of cotton as explants, the effect of sonication treatment and virulence genes in Agrobacterium tumefaciens on transformation efficiency was investigated. The pat gene which encodes resistance to the herbicide, glufosinate, was used as a selectable marker. Transformation efficiency was evaluated on th basis of survival rates of cocultivated shoot tips on selection medium containing 2.5 mg/l gulfosinate-ammonium(ppt) adn 25. mg/l Clavamax. Sonication from 5 to 15 second has a positive effect on shoop tip survival. However, whil virE as well as virG or vir GN54D showed an enhancement in transformation efficiency, virE,. virG resulted in the most significant enhancement. Overall, the combination of additional virG/virE gene and sonication treatment resulted in the most significant increase in transformation efficiency.

• Journal of Applied Biological Chemistry
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• v.56 no.1
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• pp.5-9
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• 2013

The nutritional composition of transgenic rice (Agb0101) with bar and modified cry1Ac1 genes grown with herbicides was compared with that of its non-transgenic counterpart. The analyzed components (proximates, amino acids, fatty acids, minerals, vitamins, trypsin inhibitors, and phytic acid) in the herbicide-treated Agb0101 brown rice were substantially equivalent to those of its non-transgenic counterpart.

• The Korean Journal of Pesticide Science
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• v.19 no.2
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• pp.134-140
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• 2015

We studied to compare with the effect on the shoot growth and yield relavant to weed control methods in peach. As the results about 10 day intervals and 3 times investigation after each primary treatment, treatment plot of 2 times and 3 times with the herbicide, glufosinate ammonium, were 98.2~98.6% into $10^{th}$ day, 78.6~79.6% into $20^{th}$ day, 40.7~41.1% into $30^{th}$ day, fabric covering treatment showed 100%, 100% and 97.5% and treatment plot of machinery weeding were 92.1%, 56.4% and 36.4%, respectively. Also, we compared shoot growth for pre- and post-harvest. In the results, most of weed control methods showed better growth than control. Thus, the average number of standard fruits for treatment plot of 2 times with the herbicide and that of machinery weeding was different significantly in relation to control. Therefore, we think that the herbicide henceforth is well worth the application because treatment of 2 times or 3 times with the herbicide showed significant the control effect against all of 14 weed species surveyed in peach orchard and thus no inhibition for growth and number of standard fruits in peach trees.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.183-187
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• 1999

To establish an efficient screening system for new herbicides using plant cultured cells, responses of tobacco photomixotrophic cultured (PH) cells to various herbicides with different modes of action were surveyed by measuring the cell growth and ion conductivity in medium. The cells were cultured in Murashige and Skoog (MS) medium containing 0.7mg/L 2,4-D, 0.3mg/L kinetin and 30 g/L sucrose at $25^{\circ}C$ in the light (100 rpm). Chemicals were treated to suspension cultures of tobacco PH cells at the time of subculture. The cell growth and ion conductivity in the medium were investigated on 12 days after chemical treatment. The ion conductivity assay gave well correlated results to the cell growth inhibition data. The responses of tobacco PM cells were dependent on the modes of action of chemicals tested. Atrazine, an inhibitor of photosynthetic electron transport (PET), strongly inhibited both the cell membrane and cell growth ($IC_{50}$/, about 1 $\mu$M). Butachlor (an inhibitor of cell division), glufosinate (an inhibitor of amino acid biosynthesis), and fluridone (an inhibitor of carotenoid biosynthesis) showed a dose-dependent inhibition. However, Quinclorac, a herbicide with an auxin activity, did not affect the cell growth and ion leakage. These results suggested that tobacco PM cells is suitable materials for the simple screening of new herbicides such as PET, amino acid biosynthesis, ceil division inhibitors by measuring the cell growth and ion conductivity.