• 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.

• Korean Journal of Plant Taxonomy
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• v.37 no.4
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• pp.545-563
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• 2007

The investigated vascular plants of Dok-do island were confirmed that consisted of 46 species, 1 subspecies, 1 varieties in total of 48 taxa growing spontaneously. 1 taxa of Pteridophyta, 36 taxa of Dicotyledon and 11 taxa of Monocotyledon identified. In 48 identified taxa in this study, total 13 taxa included Orobanche coerulescens Stephan, Fallopia sachalinensis (F. Schmidt) Rouse Decr., Lonicera insularis Nakai identified according to the Korean plant taxa for environmental assessment. Planting species were about 10 taxa included Pinus thunbergii Parl., Hibiscus syriacus L. and etc. Four species confirmed in this study such as between Chenopodium virgatum Thunb. and Chenopodium album L., Echinochloa crusgalli (L.) P.Beauv. and Echinochloa crusgalli var. oryzicola (Vasinger) Ohwi. were doubt on identification in taxonomic entity due to morphological characteristics. The dispersion type of Do-kdo plants were anemochore 31 taxa, zoodchore 8 taxa, hydrochore 2 taxa and the others by artificial means.

• 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.8 no.3
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• pp.273-282
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• 1988

The seventeen barnyardgrass [Echinochloa crus-galli (L.) Beauv.] accessions, which were collected national-widely in 1986 and selected two times through 1987, were experimented at 1988. To study the degree of ecological variations of the collected accessions of native barngardgrass species as a weed, the experiment was conducted with Wagner pots in size of 1/5000a and under P.E. film house. Among 57 characters, 100 grains weight, rate of tiller increase from transplanting to 30 days, the number of the maximum tillers and rate of dry weight increase from 15 DAS to 22 DAS were become intra-specific variarions as higher coefficient of varation than 30%, the size of the first leaf, fresh weight and dry 22 seedlings, rate of productive tiller, panicle number and tillering divergence made intra-specific variations as more and less C. V. than 25%, while the required days upto heading since seeding at June 6. rate of fresh/dry weight and plant height of 22 days old seedling made intra-specific variations as the coefficient of variation of about 50%. Among the attributes the color in leaf, leaf sheath, mid-ribs, node, spike, grain, and plant type, length of leaf marginal tooth, grain shape, purple bend on leaf were seemed useful to indentify the accessible specific.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.59-66
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• 1986

This experiment was conducted with pot trial to evaluate effects of pretilachlor [2-chloro-2', 6'-diethyl-N(n-propoxythyl) acetanilide], pyrazoxyfen [ 1,3-dimethyl-4-(2,4-dichloro benzoyl)-5-phenacyloxy-pyrazole], pyrazolate (4-(2,4-dichloro benzoyl)-1,3-dimethyl-pyrazol-5-yl-p-toluenesulphonate] and their combinations on Echinochloa crew-galli. Herbicides were treated with different dosages under 3 cm water depth at 1st and 2nd leaf stages of E. crus-galli. E. crus-galli showed stunted symptom by treatment of pretilachlor and etiolation by treatment of pyrazoxyfen or pyrazolate after 4 days from treatment. Stunting and chlorosis degrees of E. crusgalli increased with high dosage of all herbicides at lst and 2nd leaf stage. Combination of pyrazoxyfen+pretilachlor (6+1.5)G or pyrazolate+pretilachlor (6+1.5)G showed positive synergistic effect of herbicidal action on E. crus-galli, therefore these combinations can control E. crux galli in paddy field with lower dosage than each single treatment of herbicides. Herbicidal effect of pyrazoxyfen on E. crus-galli was similar to pyrazolate in single treatment and combination with pretilachlor.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.23-27
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• 1994

Nutrient culture study was initiated to examine the selectivity of dithiopyr(S, S-dimethyl 2-difluoromethyl)-4-(2-methylpropyl)-6-(trifluoro methyl)-3, 5-pyridine dicarbothiate) in rice(Oryza sativa L.) and barnyardgrass(Echinochloa crusgalli Beauv.). Absorption and translocation of $^{14}C$-dithiopyr in rice and barnyardgrass were also investigated to determine their selective mechanism. Rice was very tolerant, but barnyardgrass was susceptible to dithiopyr. The absorption of dithiopyr was greater in barnyardgrass than in rice and most of them remained in the roots of both species. Dithiopyr was absorbed by roots and basal shoots of both species. Translocation of dithiopyr was very low but was higher in barnyardgrass than in rice. Therefore, this study suggest that the selectivity of dithiopyr between rice and barnyardgrass may be mainly attributed to the absorption and translocation of dithiopyr in plants.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.14-18
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• 1985

This experiment was conducted to characterize the weed flora in protected semi-irrigated rice seedbeds. There are 22 species in 16 genera and 12 families, consisting of 13 annual and 9 perennial weeds in protected semi-irrigated rice seedbed in Jeonbug province. The highest frequency was obtained with Echinochloa crusgalli(L.) Beauv., Cyperus difformis L., Eleocharis acicularis Rome et Schult, and Monochoria vaginalis Presl. Sites showing Simpson's index ranging from 0.1 to 0.5 reached 82% and 89% of all sites studied in 1983 and 1984, respectively. Dominant weed species were E. crus-galli and C. difformis in both years studied and the community dominance has changed from 0.67 in 1983 to 0.61 in 1984.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.25-32
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• 1986

This experiment was conducted to evaluate effect of various hormones on callus induction, and on plantlet formation on various media, and to detect of Londax [Methyl 2-[[[[[(4,6-dimethoxy pyrimidin-2-yl) amino] carbonyl] amono] sulfonyl) methyl] benzoate] and Basta[Ammonium-(3-amino-3-carboxy-propyl)-methyl phosphinate] on callus growth and reaction of succinate dehydrogenase in callus against TTC, using various species such as Eleocharis kuroguwai, Cyperus serotinus, Oryza sativa (samgangbyeo) and Echinochloa crusgalli P. Beauv. var. caudata Kitagawa. The optimal levels of 2,4-D in MS medium seems to be different among species tested, 2.0 ppm for rice and E. crusgalli, 1.0 ppm for Eleocharis kuroguwai, and 4.0 ppm for C. serotinus derived callus from shoot-tip. In case of combination of 2,4-D with BA, 1.0 plus 0.3 ppm appeared the most appropriate level to induce callus from rice and E. kuroguwai, and I.0 plus 0.1 ppm for C. serotinus and E. crusgalli. When 2,4-D treated with TIBA, 1.0 plus 0.5 ppm appeared the most appropriate rates to induce callus derived from seeds of rice, E. crusgalli, seeds of C. serotinus and E. kuroguwai, 1.0 plus 0.3 ppm for shoot-tip of C. serotinus. Positive reaction of succinate dehydrogenase against TTC was observed regardless of calli and herbicides tested, indicating that they all are alive, and these herbicides were not able to kill the calli tested within the short period of time 20 hrs treatment. Regardless of plant species used, the rate of plantlet formation from callus was very low. However, some plantlet formed from E. crusgalli at 0.8 ppm of 2,4-D plus 8.0 ppm of kinetin, and from E. kuroguwai at 1.6 ppm of 2,4-D plus 16.0 ppm of kinetin, showing effectiveness of 2,4-D with kinetin mixture treatment. No callus was induced from C. serotinus treated with Basta from $10^{-6}M$ to $10^{-3}M$. In general, rice was the least susceptible to Basta among plant species tested, followed by E. crusgalli, and E. kuroguwai. In Londax treatment, rice showed the least inhibition rate in callus growth. Callus was induced from rice even at $10^{-3}M$ of Londax. However, $10^{-3}M$ of Londax completely inhibited callus induction from the test species. Rice showed most tolerant to both herbicides, indicating the existence of different responses among plant species.

• Korean Journal of Weed Science
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• v.4 no.1
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• pp.62-68
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• 1984

This experiment was conducted to find out the possibility for reducing herbicidal dose of the recommended herbicides in combining with the plant growth regulator "chlorflurenol" at the Yeongnam Crop Experiment Station, from 1981 to 1982. Chlorflurenol itself exhibited weed suppression effect against Monochoria raginalis Presl., Rotala indica Koehne, Cyperus difformis L., Lindernia procrembens Philcox, etc. and its effect increased as the concentrations of chlorflurenol increased from 100 to 1,000 ㎖/㏊. Combination of chlorflurenol with butachlor or thiobencarb, showing synergistic effect, reduced their recommended herbicidal rates by 50 to 75%, showing 90% of weed control rate, stic but combined treatment between chlorflurenol and bentazon showed an antagonistic effect since bentazon had poor control ability to Echinochloa crusgalli Beauv. An application of chlorflurenol showed no significant effect on rice growth, in terms of dry weight, but it resulted in the decrease in the ratio of leaf blade to other non-photosynthetic organ.

• Korean Journal of Weed Science
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• v.1 no.1
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• pp.69-77
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• 1981

Six herbicides were evaluated to investigate the phytotoxicity of rice plant and the weeding efficacy influenced by the time of application in mechically transplanted paddy field. The amount of each chemical applied was 3 kg, a. i, /ha. Chlormethoxynil : Rotala indica KOEHNE and Lindernia pyxuiaria PHILCOX were effectively controlled when applied on the 12th day after transplanting (12 DAT) and this herbicide was excellent for the control of Echinochloa crusgalli P. BEAUV, Monochoria vaginalis PRESL and Sagittaria pygmaea MIQ, when applied early (7 days after puddling) but its weeding effect for these weeds decreased greatly as the application time became later. It had a controlling effect for Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB and Scirpus hotarui ROXB at the initial period at the earlier application time. Butachlor was effective in controlling E. crusgalli, R. indica and L. pyxidaria at 12 days after transplanting (DAT) but was not effective in controlling P. distinctus and S. pygmaea even at the early application time. M. vaginalis, C. serotinus and S. hotarui were effectively controlled by the butachlor treatment at 7 days after final puddling (2 DBT-SDAT) but this weeding effect decreased at the late application time. A combination of butachlor and naproanilide excellently controlled E. crusgalli, R. indica, L. pyxidaria and S. pygmaea regardless of the application time. For the control of M. vaginalis, C. serotinus and P. distinctus, the weeding effect of this mixtures was much greater than that of the single treatment of butachlor. Perfluidone was excellent for the control of E. crusgalli, R. indica, L. pyxidaria, M. vaginalis and S. pygmaea at either application time tested. P. distinctus, C. serorinus and S. hotarui could be controlled by this chemicals until the time of first observation (23 DAT) but the effect for these weeds somewhat decreased as time passed. The effect of pyrazolate on E. crusgalli, M. vaginalis, S. hotarui and P. distinctus was very excellent regardless of the application time but R. indica and L. pyxidaria could not be completely eliminated by this chemical. This chemical was effective in controlling C. serotinus when applied at 7-9 days after final puddling and showed a controlling effect for S. hotaruionly at the initial period. Piperophos + dimethametryn was very excellent for the control of all the annual weeds and P. distinctus. It showed a controlling effect on S. pygmaea, C. serotinus and S. hotarui only at the initial period. There was no difference in the effects on phytotoxicity and yield between chlormethoxynil and pyrazolate at either times of application tested. The later the application time was, the less the phytotoxicity of butachlor and piperophos+dimethametryne was. The phytotoxicity of butachlor + naproanilide and perfluidone decrease in the plots treated at the later application time. When the last two chemicals were treated at 2 days before transplanting (DBT) the yield decreased as compared with the hand weeded plot.