• Korean Journal of Weed Science
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• v.5 no.2
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• pp.187-193
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• 1985

The experiment was carried out to evaluated the interaction between perfluidone(2-methyl-4-phenylsulphonyltrifluoromethylsulphoanilide) and bifenox(2,4-dichlorophenyl-3-methoxycarbonyl-4-nitrophenylether). A synergistic effect was found between perfluidone and bifenox. The highest synergistic effect on Echinochloa crus-galli (L.). Beauv. was obtained when 10 g a.i./10a of perfluidone was combined with 24.9 g a.i./10a of bifenox. However, bifenox should be increased to 33.3, g a.i./10a to obtain the highest synergistic effect when applied to Cyperus serotinus Rottb. at 1.0-1.5 leaf stage. Sagittaria pygmaea Miq. at 0.5-1.0sleaf stage was completely controlled by the lowest combination rate employed.

• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.300-308
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• 2000

The degradation of herbicide $^{14}C-bifenox$ was studied in soils under anaerobic conditions. $^{14}C-bifenox$ was treated in silty loam and sandy loam soils, respectively at a rate of 2.1 mg/kg, and the soil was incubated under anaerobic conditions at $25^{\circ}C$ for 180 days. The mineralization, solvent extractable and non-extractable residues, degradation products of bifenox were investigated during the experiments. The relative amounts of $^{14}CO_2$ were 1.97 and 0.9% of applied $^{14}C$ in silty loam and sandy loam soils, respectively. The non-extractable residues of sandy loam soil increased dramatically up to 79.12% of applied $^{14}C$, and were higher than those of silt loam soil, suggesting physico-chemical properties and especially organic matter contributed to the difference of $^{14}C$ between two soils. The non-extractable residues were formed mainly humin fraction and increased with time. The major metabolites were nitrofen, 5-(2,4-dichlorophenoxy)-2-Nitrobenzoate, 2,4-dichlorophenoxy aniline and methyl 5-(2,4-dichlorophenoxy) anthranilate by GC/MS analysis. From the results of volatilization, mineralization and degradation of bifenox, bifenox was stable chemically and biologically in soil.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.194-201
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• 1985

Effect of perfluidone(2-methyl-4-phenylsulphonyltrifluoromethylsulphoanilide) and bifenox(2,4-dichlorophenyl-3-methoxycarbonyl-4-nitrophenylether) mixture on weed control and plant growth and yield of transplanted rice was determined. Perfluidone-bifenox mixture applied at 75-105 g a.i./10a controlled effectively perennial weeds such as Sagittaria pygmaea Miq., Potamogeton dtstinctus A. Benn., Cyperus serotinus Rottb, Eleocharis kuroguwai Ohwi, including most annual weeds, but did not control Sagittaria trifolia L.. There was no phytotoxicity caused by perfluidone-bifenox mixture when applied at 100-140 g a.i./10a. The mixture at 150-210 g a.i./10a caused crop injury, but did not affect the yield. Phytotoxicity due to the mixture decreased as the application time was delayed.

• Korean Journal of Weed Science
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• v.2 no.1
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• pp.47-52
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• 1982

This experiment was conducted to evaluate weed control effect of Butachlor, Oxadiazon, and Bifenox under three levels of water depth (0, 3, 6 cm). Number of E. crusgall. and M. vaginalis decreased as water depth increased while that of P. distinctus showed the opposite trend. Water depth did not influence number of E. kuroguwai and C. serotinus. Weed control effect of Butachlor and Oxadiazon was best at 3 cm water depth at while that of Bifenox was best at 6 cm water depth. Injury of Butachlor to rice decreased as water depth increased while that of Oxadiazon and Bifenox showed opposite trend.

• Korean Journal of Weed Science
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• v.16 no.4
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• pp.337-345
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• 1996

This study was conducted to investigate the protox activity, the PPIX accumulation and the activity of antioxidative enzymes of the oxyfluorfen-tolerant and -susceptible rice cultivars by oxyfluorfen and oxytluorfen-similar herbicides treatment. When treated with acifluorfen, bifenox or oxadiazon, the oxyfluorfen-tolerant rice cultivars showed less decreased in fresh weight than the susceptible rice cultivars. The inhibition of protox activity was in the order of acifluorfen > oxyfluorfen > bifenox > oxadiazon, and the PPIX accumulation was in the sequence of oxadiazon > acifluorfen > oxyfluorfen > bifenox. The inhibition of protox activity and the PPIX accumulation by the herbicide was greater in the susceptible rice cultivars than in the tolerant rice cultivars. The effect inhibiting the decrease of chlorophyll content resulting from the treatment of GC, tetrapyrrole biosynthesis inhibitor, was in the order of oxyfluorfen > acifluorfen > bifenox > oxadiazon, and the tolerant rice cultivar had more than the susceptible rice cultivar. In the treatment of DPE and oxadiazon, the activities of MDAR, POX and GR was higher in the tolerant rice cultivar than in the susceptible rice cultivar, and in the case of POX isozyme the activities of main D and E bands increased in the tolerant rice cultivars at tested herbicides but they didn't in the susceptible rice cultivar.

• 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.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.104-116
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• 2018

BACKGROUND: This experiment was conducted to establish a simultaneous analysis method for 7 kinds of herbicides in 3 different classes having similar physicochemical property as diphenyl ether(bifenox and oxyfluorfen), dinitroaniline (ethalfluralin and trifluralin), and chloroacetamide (metolachlor, pretilachlor, and thenylchlor) in crops using GC-ECD/MS. METHODS AND RESULTS: All the 7 pesticide residues were extracted with acetone from representative samples of five raw products which comprised apple, green pepper, Kimchi cabbage, hulled rice and soybean. The extract was diluted with saline water and directly partitioned into n-hexane/dichloromethane(80/20, v/v) to remove polar co-extractives in the aqueous phase. For the hulled rice and soybean samples, n-hexane/acetonitrile partition was additionally employed to remove non-polar lipids. The extract was finally purified by optimized Florisil column chromatography. The analytes were separated and quantitated by GLC with ECD using a DB-1 capillary column. Accuracy and precision of the proposed method was validated by the recovery experiment on every crop samples fortified with bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin at 3 concentration levels per crop in each triplication. CONCLUSION: Mean recoveries of the 7 pesticide residues ranged from 75.7 to 114.8% in five representative agricultural commodities. The coefficients of variation were all less than 10%, irrespective of sample types and fortification levels. Limit of quantitation (LOQ) of the analytes were 0.004 (etahlfluralin and trifluralin), 0.008 (metolachlor and pretilachlor), 0.006 (thenylchlor), 0.002 (oxyfluorfen), and 0.02 (bifenox) mg/kg as verified by the recovery experiment. A confirmatory technique using GC/MS with selected-ion monitoring was also provided to clearly identify the suspected residues. Therefore, this analytical method was reproducible and sensitive enough to determine the residues of bifenox, ethalfluralin, metolachlor, oxyfluorfen, pretilachlor, thenylchlor, and trifluralin in agricultural commodities.

• Korean Journal of Environmental Agriculture
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• v.14 no.1
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• pp.88-96
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• 1995

The research was carried out in tray ($0.12m^2$) in greenhouse ($30{\pm}2^{\circ}C$${\sim}$$25{\pm}2^{\circ}C$) equipped with Auto Foggy System (SAE KI RIN Co.) and results are summarized as follows: 1. Bifenox and bensulfuron retarded the growth of rice under foggy condition and the weeding efficacy among the herbicides tested was not different. 2. Weeds under foggy condition emerged at smaller amounts than under the non-foggy condition. bensulfuron, molinate and bifenox showed the high weeding efficacy. There was a tendency that molinate reduced the number of tillers at 20 and 60 days after transplanting. 3. Among the herbicides tested, only the molinate reduced the dry weight and yield of rice significantly.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.188-193
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• 1984

Interactions of herbicide mixtures were assessed for effective control of annual and perennial paddy weeds by isobole method(90% control) using Echinochloa crusgalli Beauv. var. oryzicola Ohwi, Scirpus hotarui Ohwi, Sagittaria pygrnaea Miquel, and Cyperus serotinus Rottb which are dominated in the paddy field of Korea. Mixture of butachlor and pyrazolate showed additive effect for control of E. crusgalli Beauv. var. oryzicola Ohwi, S. hotarui Ohwi and C. serotinus Rottb, but synergistic effect for control of S. pygmaea Miquel. Interaction of bifenox and bromobutamide showed synergistic effect to E. crusgalli Beauv. var oryzicola Ohwi and C. Serotinus Rottb, but slightly antagonistic effect to S. pygmaeo Miquel.

• Korean Journal of Weed Science
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• v.16 no.1
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• pp.54-63
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• 1996

This study was conducted to investigate the anatomical and ultrastructural responses of the oxyfluorfen-tolerant and -susceptible rice cultivars with barnyardgrass, a typical susceptible weed by oxyfluorfen and the herbicides having similar mode of action treatment. After the treatment of $10^{-5}M$ oxyfluorfen, the tolerant rice cultivars no showed the structural damage of leaf surface, but the susceptible rice cultivate was damaged in the wax and the susceptible barnyardgrass was even destroyed in the tissue irregularly. Also in the susceptible rice cultivars and barnyardgrass the thickness of leaf blade was greatly decreased. The anatomical change was not observed in the tolerant rice cultivars but epidermal cells, mesophyll cells and bundle sheath cells were badly broken in the susceptible rice cultivars and barnyardgrass and especially after 24 hours of the treatment the structure of susceptible rice cultivars was completely disintegrated. The irregularity of chloroplast shape and the distortion of chloroplast envelope were generally observed and the starch tended to decrease by oxyfluorfen treatment regardless of rice cultivars. Such a structural damage were appeared more badly in the susceptible rice cultivars and bamyardgrass than in the tolerant rice cultivars. By the treatment of diphenyl ether herbicides, the thickness of leaf blade greatly reduced in the order of oxyfluorfen > acifluorfen > bifenox > oxadiazon, and the susceptible rice cultivars showed more reduction than the tolerant rice cultivars. Especially, the susceptible rice cultivars showed that the leaf structure was badly broken down with damage epidermal cells and bundle sheath cells.