• The Korean Journal of Pesticide Science
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• v.18 no.4
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• pp.258-268
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• 2014

The test method of aerobic transformation in soil has established based on international test guideline (OECD TG 307). And then, the case study was conducted with [$^{14}C$]butachlor. Butachlor is commonly used herbicide in Korea. [$^{14}C$]Butachlor was treatrd $6.83mgKg^{-1}$ in loamy soil. The treated soil was incubated in flow-through system for 60 days. The mass balance of applied radioactivity (AR) ranged from 91.1 to 95.5% and from 93.0% to 97.7% for non-sterile and sterile soils, respectively. In non-sterile soil, the concentration of [$^{14}C$]butachlor was declined from 94.4% AR at 0 day to 8.4% AR at 60 days after treatment. 2-Chloro-2',6'-diethylacetanilide was the major degradation product detected in soil extract. The calculated $DT_{50}$ and $DT_{90}$ of butachlor were 10.4 days and 34.6 days, respectively. $^{14}CO_2$ and non-extractable soil residue were increased up to 3.5% and 43.5% AR at 60 DAT. There is no significant decrease of the [$^{14}C$]butachlor through the incubation period in sterile soil.

• Korean Journal of Weed Science
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• v.9 no.3
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• pp.245-249
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• 1989

The effects of varying concentrations and durations of butachlor [N-(bytoxymety 1,)-2-chlor -2, 6-diethy lacetanilide treatment on oat(Avena sativa L.) root cell division and protein synthesis were studied. The highest concentration ($1{\times}10^{-3}M$) of butachlor caused the significant inhibition of cell division after 18hrs treatment. After 18hrs treatment, 59% and 82% inhibition of cell division occurred at $1{\times}10^{-4}M$ and $1{\times}10^{-3}M$, respectively, while 9% inhibition of cell division did at $1{\times}10^{-6}M$ concentration at the same exposure period. To investigate protein synthesis, the oats were treated for 18 and 24hrs with concentrations ranging from $1{\times}10^{-6}M$ to $1{\times}10^{-3}M$ butachlor. After 18hrs, butachlor treatment of oat with $1{\times}10^{-4}M$ inhibitited 23% protein synthesis, and butachlor treatment with $1{\times}10^{-4}M$ caused 34% inhibition after 24hrs. With SDS-PAGE of proteins extracted from oat root tips, butachlor usually inhibited the 16, 18, 30, 43 and 43.5 kD polypeptide, and proteins of root tips are made up of subunits below 100 kD polypeptide.

• Korean Journal of Environmental Agriculture
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• v.4 no.2
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• pp.118-125
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• 1985

To establish an evaluation system of aquatic toxicity of chemicals at no-effect level, flow through and early life stage toxicity test were performed on a freshwater fish, the medaka (Oryzias latipes). The characteristics of medaka as a bioassay organism for the chronic toxicity test were discussed. Maximum acceptable toxicant concentration(MATC) of butachlor for the madaka in soft water was estimated using survival, growth, and reproduction as indicators of toxic effects. During a 3-month period, the fry of medaka were exposed to butachor concentrations ranging from 0.16 to 0.0l mg/liter and the DO concentration, temperature, and pH in the exposure chamber were measured to check the test condition. The highest concentration showed slight decrease of growth rate in medaka and reduced hatchability of spawning egg. Survival, growth, and reproductive success of adults in butachlor concentration of 0.04 and 0.01 mg/liter were not different from those of the control. The MATC was estimated to be between 0.04 and 0.16 mg/liter for medaka.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.164-168
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• 1985

In order to enhance herbicidal efficacy of amide and diazine herbicides, synergistic effects of pretilachlor and pyrazoxyfene or butachlor and pyrazolate on control of Cyperus serotinus were determined by isobole method. Interaction indices(I) between pretilachlor and pyrazoxyfene treated at 0 and 3rd leaf stage were 2.64 and 2.07 and hence showed synergistic effect for control of Cyperus serotinus. The points indicated Imax between pretilachlor and pyrazoxyfene were 0.7:1.3 g ai/a and 9.0:20.5 g ai/a at 0 and 3rd leaf stage, respectively. Combination of butachlor and pyrazolate showed synergistic effect(1=1.57) on control of Cyperus serorinus and point indicated Imax was 48.0:20.9 g ai/a.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.1-12
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• 2012

The present study examines the effects of 30 mg/kg butachlor on the cyanobacterial diversity of rice fields in Eastern Uttar Pradesh and Western Bihar in India. A total of 40 samples were grouped into three classes [(i) acidic, (ii) neutral, and (iii) alkaline soils], based on physicochemical and principle component analyses. Acidic soils mainly harbored Westillopsis, Trichormus, Anabaenopsis, and unicellular cyanobacteria; whereas Nostoc, Anabaena, Calothrix, Tolypothrix, and Aulosira were found in neutral and alkaline soils. Molecular characterization using 16S rRNA PCR and DGGE revealed the presence of 13 different phylotypes of cyanobacteria in these samples. Butachlor treatment of the soil samples led to the disappearance of 5 and the emergence of 2 additional phylotypes. A total of 40 DGGE bands showed significant reproducible changes upon treatment with butachlor. Phylogenetic analyses divided the phylotypes into five major clusters exhibiting interesting links with soil pH. Aulosira, Anabaena, Trichormus, and Anabaenopsis were sensitive to butachlor treatment, whereas uncultured cyanobacteria, a chroococcalean member, Westillopsis, Nostoc, Calothrix, Tolypothrix, Rivularia, Gloeotrichia, Fischerella, Leptolyngbya, and Cylindrospermum, appeared to be tolerant against butachlor at their native soil pH. Butachlor-induced inhibition of nitrogen fixation was found to be 65% (maximum) and 33% (minimum) in the soil samples of pH 9.23 and 5.20, respectively. In conclusion, low butachlor doses may prove beneficial in paddy fields having a neutral to alkaline soil pH.

• Journal of Applied Biological Chemistry
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• v.49 no.3
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• pp.101-105
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• 2006

Degradation of the herbicide butachlor was investigated using laboratory-synthesized zerovalent iron ($Fe^0$). The synthesized zerovalent iron was determined to be nanoscale powder by scanning electron microscopic analysis. To investigate degradation of butachlor using the synthesized nanoscale zerovalent iron, time-course batch experiments were conducted by treating the solution of butachlor formulation with the iron. More than 90% degradation of butachlor was observed by iron treatment within 24 h. The synthesized nanoscale zerovalent iron showed an increase in particle aggregation in the batch tests. Green rust formation and a pH drop in solutions were observed, suggesting that the oxidation of the iron occurred. When the iron was extracted with dichloromethane, a negligible concentration was found in the extract, suggesting that butachlor did not bind to the iron particles. GC/MS analysis detected the dechlorinated product as a major degradation product of butachlor in the solutions. The data indicate that laboratory-synthesized zerovalent iron functioned as a reductant to remove electron-withdrawing chlorine, giving the dechlorinated product.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.31-40
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• 1982

For the effective control of weeds in mechanically transplanted paddy field weeding effects of naproanide ${\alpha}$-(${\beta}$-naphthoxy) propion anilide], pyrazolate [4-2, 4-dichlorobenzoyl)-1, 3-dimethyl pyrazol-5-yl-p-tolune sulphanate], chlormethoxynil (2, 4-dichloro-phenyl-4-nitro-3-methoxy phenyl ether), SL-49 [1-3dimethyl-4(2, 4dichlorobenzoyl)-5-phenacyloxy pyrazole], ACN (3-chloro-2-amino-l, 4-naphthoquinone) either alone or in combination with butachlor (2-chlor-2, 6-diethyl-N-buthoxymethyl acetanilide) were compared. Pyrazolate and SL-49 were most effective for the control of Sagittaria pygmaea MIQ. and Potomogeton distinctus A. BENN. including most annual weeds. Weeding effect of butachlor alone was very high for annuals, good for Cyperus serotinus ROTTB. and poor for S. pygmaea and P. distinctus. But the weeding effect of the combination of butachlor and pyrazolate was stronger than that of butachlor alone and therefore this mixture was effective for S. pygmaea, P. distinctus and C. serotinus including all the annual weeds. The combination of butachlor and SL-49 showed the same tendency as the combination of butachlor and pyrazolate. Naproanilide was not effective for the control of Echinochlor crusgalli P. BEAUV and less effective for Monochoria vaginalis PRESL, but excellent for S. pygmaea. By mixing butachlor with naproanilide weeding, spectrum for annuals and S. pygmaea was much increased by that for P. distinctus and C. serotinus was not satisfactory. ACN was not satisfactory for the control of all the tested weeds but the weeding effect was increased in general by mixing with butachlor. Chlormethoxynil was excellent for the control of annual weeds but it has no effect on C. serotinus, S. pygmaea and P. distinctus showing some initial controling effect but these weeds regrew afterwards. The weeding activity of ACN increased in combination with butachlor and the residual activity was stronger than that of ACN alone. A light crop injury was found at the initial period after treatments in all treated plots. The yield from all treated plots except those from plots treated with ACN, butachlor and naproanilide were not significantly different from the band weeded plot.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.309-319
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• 2002

Soil adsorption study was carried out to define the mobility of pesticides or to evaluate leaching potential in soils. Five pesticides including ethoprophos, procymidone, iprobenfos, isoprothiolane, and butachlor were subjected to optimized adsorption experiment protocol for three types of cultivation soils. Freundlich adsorption coefficients (K) were ranged $0.35{\sim}0.95$ for ethoprophos, $0.98{\sim}2.2$ for iprobenfos, $1.2{\sim}4.3$ for procymidone, $1.5{\sim}3.5$ for isoprothiolane and $7.9{\sim}19$ for butachlor in three soils. Based on Koc values, ethoprophos was classified as mobile, iprobenfos, isoprothiolane and procymidone as moderately mobile and butachlor as slightly mobile. Two evaluation methods, Groundwater Ubiquity Score (GUS) index and standard indices of soil-chemical adsorption and biodegradation, were used for the estimation of pesticide leaching potential. Leachability of isoprothiolane and iprobenfos were evaluated as moderate, ethoprophos as a little potential, while butachlor and procymidone showed very low leaching potential. The leaching potential of pesticides was essentially determined on the basis of intrinsic properties of the pesticides and environmental properties. Among the soil properties, organic matter gave a great influence on the leachability of soils. Therefore, leachabilities of pesticides were expected less in loam with relatively higher organic matter than clay loam with lower organic matter.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.154-162
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• 1984

The persistence of butachlor and nitrofen in different soil conditions applied organic matter, lime, and other pesticides was studied under submerged and field moisture capacity. Degradation of the herbicides in soil was significantly retarded by autoclaving the soil and half-life of nitrofen was much longer than that of butachlor under this condition. Submerging the soil enhanced degradation of the herbicides, in particular that of nitrofen. On the other hand, half-life of nitrofen under field moisture capacity was twice longer than that of butachlor. Increased amendment of rice straw to the soil shortened the half-life of nitrofen under submerged soil, however it prolonged that of butachlor when the amendment was exceeded 1000kg/10a level. Liming the soil stimulated herbicide decomposition in the soil, which appears to be pH independent. Butachlor degradation in submerged soil was slightly stimulated by simultaneous application of fungicides and insecticides, but nitrofen persistence was not influenced.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.9-13
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• 1985

This study was conducted to evaluate herbicide resistant plant through tissue culture. Callus was induced from embryos of Echinochloa crusgalli Beauv. (var, oryzicola Ohwi, var. caudata Kitagawa and var, crusgalli). An optium medium for callus induction and succinate dehydrogenase activity in inducted callus were detected and callus growth of various varieties of Echinochloa crusgalli was assessed under the treatment of various rates of butachlor[N-(butoxymethyl)-2-chloro-N-(2,6-diethylphenyl)acetamide]. MS medium seemed to be the most appropriate to induce callus from the embryos of varieties of E. crusgalli by using 2,4-D about 5.5mg/l as a hormone source. The activity of succinate dehydrogenase in inducted callus showed positive reaction against to TTC(2,3,5-triphenyltetrazolium chloride) regardless of concentrations of butachlor and varieties of E. crusgalli, indicating that all the callus induced were alive. The callus growths derived from seeds of E, cnesgalli were greatly affected by various rates of butachlor and were completely inhibited at the highest concentration of butachlor, $10^{-3}M$, regardless of varieties of E. crasgalli. $10^{-6}M$ of butachlor inhibited 24.6% of the callus growth of E. crusgalli Beauv, var. oryzicola Ohwi, while E. crusgalli Beauv. var. crusgalli showed 42% of inhibition, showing that there was difference in response of varieties of E. crusgalli Beauv. to butachlor.