• Korean Journal of Soil Science and Fertilizer
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• v.13 no.1
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• pp.45-51
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• 1980

The effects of propanil, MCPA; 2, 4 5-T and silvex on the numder of new root and tiller on Taichung Native 1, Caloro, PI 245717 and Bluebonnet 50 by root administration and foliar spray at 10 levels of concentration were investigated. Phenoxy herbicides changed the growth pottern in the way of increased number of tillers and new roots rather than plant height or root length. It was suggested that MCPA is only possible to increase tillering around applicable range. Silvex stimulated tillering at higher level than that required to stimulate new root formation. Varietal response on herbicides were different along with herbicide feeding part. There was trends that the higher nitrogen response varieties also have a greater response to stimulating effect of herbicide. Propanil had no effect on growth and no injury even about 20 times of higher concentration of phenoxy herbicide.

• Current Research on Agriculture and Life Sciences
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• v.17
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• pp.65-70
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• 1999

This study was conducted to develop a simple selection method for herbicide-resistance weeds. Two methods, designated "seedling method" and "stem node method" were employed for screening of barnyardgrass against propanil and butachlor. In the seedling method, shoot and root growth of barnyardgrass were significantly inhibited at quarter of the recommended herbicide rate, while in the stem node method, the similar inhibition was obtained at half of the recommended rate. Thus, it was concluded that the seedling method is more simple and quick method to evaluate response of barnyardgrass to propanil and butachlor compared to stem node method.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.39-45
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• 1989

An experiment was conducted at the Yeongnam Crop Experiment Station for 4 years from 1985 to understand the effect of repeated use of same herbicide on weed growth. For this, the most common 6 herbicides, butachlor, bifenox, butachlor/pyrazolate, piperophos/dimethametryne, bentazon and propanil were used as single treatment or combination treatment. For non chemical plots, weed occurrence was rapidly increased with time in terms of number and weight. However no rice plot recorded the least increasing ratio. Similar trend was obtained at the herbicide plot even though the increasing ratio varied by herbicide properties. The least increasing ratio (1200 was recorded at the plot of butachlor/pyrazolate (5 days after transplanting, 5 DAT) followed by bentazon+propanil(25 DAT) while the greatest ratio (28%) was obtained from the plot of bifenox (5 DAT). In general, Scirpus hotarui, Eleocharis kuroguwai and Cyperus serotinus was gradually inereased with time by herbicide application, particularly at the butachlor/pyrazolate treatment. The community dominance and simpson index increased at the plot of bentazon and propanil due to increased of particular species while other herbicide plots exhibited reverse trend. Grain yield was curvilinearly decreased with weed weight for both times, 40 DAT and heading time eventhough the correlation coefficient of heading time was higher than 40 DAT.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.55-62
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• 1979

The effects of propanil, MCPA; 245-T and silvex on growth pattern were tested on Taichung Native 1. Caloro, PI 245717 and Bluebonnet 50 by root administration and foliar spray at 10 levels of concentration. Silvex in foliar spray increased plant height of Taichung and when applied via root decreased root langth of Bluebonnet and pi245717 at all levels. All phenoxy herbicides over 4 ppm - decreased plant height in all varieties tested when applied to root. General morphorogical response - were also observed.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.108-113
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• 1996

The experiment was conducted to obtain basic information on occurrence ecology system of Aneilema japonica and to establish its effective control systems in dry seeded rice at National Yeongnam Agricultural Experiment Station in 1995. Total amount of weed in dry seeded rice in the following year('95) as affected by control of barnyardgrass at 70 days after seeding(DAS) in previous year('94) was reduced 47.7% at 30 DAS and 7.8% at 60DAS and also exhibited different weed occurrence as compared with no control plot. Especially in control plot at 60 DAS, occurrence of Echinochloa crus-galli was reduced by 46.9%, But the growth of Aneilema japonica which is one of the problems in weed species was drastically increased by 231 % and Persicaria hydropiper by 11.8%, respectively. Suppressed tillering of rice plant as affected by occurring of A. japonica(300-750 plants/$m^2$) occurred from about 40 DAS and rice grain reduced 74-93% compared with hand weeding due to reduced panicle number. Soil applied Butachlor(EC) at 5 DAS, foliar applied Propanil -Butachlor(EC) at 13 DAS and Lgc 40863+Pendimethalin at 20 DAS were very effective for Aneilema japonica. As considering both weed suppression of Aneilema japonica and yield capacity, middle late foliar application of Lgc 40863+Pendimethalin and systematic application of Butachlor at 5 DAS followed by Propanil/Molinate at 25 DAS were the most effective control systems.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.79-85
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• 1988

The effects of herbicides on biochemical processes in soil environment were studied by examining the effects of the chemical structure of each herbicides on soil enzyme activities and pesticides residue revealed when soil treated with urea was incubated at $28{\pm}1^{\circ}C$ for 56 days. The inhibition effects of herbicides on soil enzyme activites in soil decreased in the order of urea group>dinoseb>propanil>diphenyl eter group>acid amide group for urease, and dinoseb>urea group>diphenyl ether group>acid amide group for L-glutaminase and protease, dinoseb>diphenyl ether group>urea group>acid amide group for phosphatase. Herbicides inhibited the activities of soil enzyme in the early stage of treatment but increased the activities of urease, L-glutaminase and protease in the late stage. When herbicides were treated in soil together with urea the degradation of insecticides was accelerated.

• Korean Journal of Environmental Agriculture
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• v.14 no.2
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• pp.163-170
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• 1995

This study was carried out to compare the acute toxicity(96hr) of 13 chemicals to carp (Cyprinus carpio L.) and israeli carp (Cyprinus israeli carpio L.) and the activities of acetylcholinesterase (AchE) and glutathione S-transferase (GST) in israeli carp exposed to five insecticides (diazinon, malathion, carbofuran, cartap, methomyl). $LC_{50}$ values of acute toxicity of the chemicals to israeli carp were endosulfan 0.0061ppm, captafol 0.041ppm, chlorothalonil 0.073ppm, butachlor 0.48ppm, captan 0.14ppm, carbofuran 1.13ppm, cartap 1.15ppm, diazinon 1.35ppm, nitrofen 3.72ppm, methomyl 4.39ppm, propanil 10.61ppm, malathion 11.78ppm and isoprothiolane 12.81ppm. The acute toxicity of endosulfan 0.0061ppm was 2100 times higher than that of isoprothiolane 12.81ppm. $LC_{50}$ values of acute toxicity of the chemicals to carp were endosulfan 0.0026ppm, captafol 0.062ppm, chlorothalonil 0.078ppm, captan 0.14ppm, and butachlor 0.47ppm, carbofuran 0.52ppm, nitrofen 0.58ppm, diazinon 0.81ppm, cartap 0.82ppm, methomyl 5.03ppm, propanil 10.67ppm, malathion 11.92ppm, and isoprothiolane 13.20ppm. The acute toxicity of endosulfan was 5,000 times higher than that of isoprothiolane. The toxicity of diazinon, carbofuran, cartap, endosulfan, and nitrofen to carp was approximately 2-6 times as high as that to israeli carp, but the toxicity of malathion, methomyl and captafol to israeli carp was slightly higher than that to carp. AchE activity was inhibited by 31% and 52% after 96hr’s exposure of israeli carp to diazinon and malathion respectively. GST activity in israeli carp was significantly induced by methomyl exposure for 96 hr.

• Korean Journal of Weed Science
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• v.6 no.2
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• pp.174-190
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• 1986

A series of laboratory and greenhouse experiments were conducted to find out the possibility of tissue culture and cell culture methods as a tool to study herbicidal behaviour and herbicide tolerance screening from 1985 to 1986 at the Yeongnam Crop Experiment Station. For dehulled-rice culture, pure agar medium was the most appropriate in rice growth campared to other media used for plant tissue culture method. All the media but the pure agar medium resulted in growth retardance by approximately 50% and this effect was more pronounced to root growth than shoot growth. Herbicidal phytotoxicity was enhanced under light condition for butachlor, 2.4-D, and propanil while this effect was reversed for DPX F-5384 and CGA 142464, respectively. And also, herbicides of butachlor, chlornitrofen, oxadiazon, and BAS-514 resulted in more phytotoxic effect when shoot and root of rice were exposed to herbicide than root exposure only while other used herbicides exhibited no significant difference between two exposure regimes. Similar response was obtained from Echinochloa crusgalli even though the degree of growth retardance was much greater. Particularly, butachlor, 2.4-D, chlornitrofen, oxadiaxon, pyrazolate and BAS-514 totally inhibited chlorophyll biosynthesis even at the single contact of root. Apparent cultivar differences to herbicide were observed at the young seedling culture method and dehulled rice cultivars were more tolerant in DPX F-5384, NC-311, pyrazolate and pyrazoxyfen, respectively. For derant than other types or rice cultivar in butachlor, pretilachlor, perfluidone and oxadiazon while Tongil-type rice cultivars were more tolerant in DPXF-5384, NC-311, Pyrazolate and Pyrazoxyfen, respectively. For dehulled rice culture, on the other hand, Japonica-type rice cultivar was less tolerant to herbicides of butachlor, propanil, chlornitrofen and oxadiazon that was reversed trend to young seedling culture test. Cultivar differences were also exhibited within same cultivar type. In general, relatively higher tolerant cultivars were Milyang 42, Cheongcheongbyeo, Samgangbyeo, Chilseoungbyeo for Tongil-type, Somjinbyeo for Japonica-type and IR50 for Indica-type, respectively. The response of callus growth showed similar to dehulled rice culture method in all herbicides regardless of property variables. However, concentration response was much sensitive in callus response. The concentration ranges of $10^{-9}M-10^(-8)M$ were appropriate to distinguish the difference between herbicides for E. crusgalli callus growth. Among used herbicides, BAS-514 was the most effective to E. crusgalli callus growth. Based on the above results, tissue culture method could be successfully used as a tool for studying herbicidal behaviour and tolerance screening to herbicide.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.3-10
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• 1991

Several rice herbicides were evaluated to determine the herbicidal efficacy on dry seeded paddy rice. The time of herbicide application was within 1 day after seeding(DAS), 18 DAS, and 40 DAS. Under the upland conditions 30 DAS(before permanent flooding) dominant weed species were Echinochloa sp., Digitaria sp., Leptochla sp., weedy rice and other several annual broadleaved weeds belonging to Cruciferae, but after flooding Echinochloa sp., Aeschynomene sp., Eleocharis kuroguwai, Cyperus sorotinus, Ludwigia prostrata, Aneilema japonica were dominat. Early application (1 DAS) of thiobencarb, pyrazolate/butachlor, or chlomethoxyfen/butachlor resulted in very good herbicidal efficacy only during the first 30 days, but not thereafter. Application of propanil+butachlor on 18 DAS did not control the late occurring weeds effectively. Application of bentazone/quinchlorac on 40 DAS successfully suppressed weed growth throughout the remaining rice growing season and showed similar grain yield as hand weeded plot. Weed growth reduced the plant height, panicle number, 1000-grain weight, percent ripened grains, and grain yield of rice by 7, 82, 19, 55 and 87% respectively. There was a positive linear relationship between weed weight and lodging index of rice.

• The Korean Journal of Pesticide Science
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• v.12 no.4
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• pp.421-428
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• 2008

This study was carried out to elucidate the effects of adjuvants on physicochemical properties and pest control efficacy of pesticide spray solution. Spray droplet sizes of pesticide solution decreased by addition of adjuvants even though its effect varied according to the pesticides. The adhesive effect of pesticides sprayed on target crops by addition of adjuvants varied according to the properties, the application methods, and the spray volume of pesticides. Wash-off of the deposited amount of active ingredients of the solution of tricyclazole WP and fenobucarb EC by simulated rainfall after spraying on rice plants dramatically reduced by adding adjuvants. The retained amount of active ingredients of the pesticides were $1.5{\sim}4.1$ times higher than those without adjuvants when subjected to simulated rainfall 6 hours after spraying. Addition of adjuvants to the propanil EC spray solution enhanced the control efficacy in barnyard grass, Echinocloa crus-galli Beauv. by $8{\sim}30%$, which showed a potential to reduce pesticide use.