• Korean Journal of Weed Science
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• v.7 no.1
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• pp.64-73
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• 1987

Field and greenhouse trials were conducted to evaluate application variables including spray volume, surfactant, and simulated rain affecting phytotoxicity of glyphosate for enhancing efficacy of postemergence herbicides. Glyphosate phytotoxicity was increased by addition of surfactants, L-77 and Triton CS-7 to glyphosate solution in Artmesia princeps and Equisetum arvense and addition of Triton CS-7 to glyphosate solution enhanced control of Trifoliurn repens. Simulated rain within 4 or 8 hours after glyphosate application reduced glyphosate phytotoxicity. However, addition of L-77 and Triton CS-7 to glyphosate solution increased glyphosate phytotoxicity reduced by simulated rain in Artmesia princeps and Trifolium repens.

• The Korean Journal of Pesticide Science
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• v.10 no.3
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• pp.225-229
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• 2006

This study was conducted to screen herbicidal activity of Korean native plants which could be used for the development of new natural herbicides. Fifty-five plants were collected from Wan and Jeju islands in Korea and their methanol extracts were obtained. Herbicidal activity of methanol extracts were determined by seed bioassay using rape (Brassica napus L.) seedlings. Among fifty-five species, five plants were highly herbicidal ($GR_{50}$ < 1,000 ${\mu}g\;g^{-1}$): Clematis apiifolia A. P. DC.; (811 ${\mu}g\;g^{-1}$), Euscaphis japonica (THUNB.) KANITZ (867 ${\mu}g\;g^{-1}$), Hibiscus mutabilis L. (988 ${\mu}g\;g^{-1}$), Phyllostachys pubescens MAZEL (778 ${\mu}g\;g^{-1}$), Yucca recurvifolia (857 ${\mu}g\;g^{-1}$). Twenty-seven plants were shown moderately herbicidal (1,000 < $GR_{50}$ < 2,000 ${\mu}g\;g^{-1}$), however, twenty-three plants were not shown any herbicidal activity.

• The Korean Journal of Pesticide Science
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• v.9 no.2
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• pp.173-180
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• 2005

This study was conducted of Korean native plants to screen herbicidal activity which could be used for the development of new natural herbicides. Eighty-one plants were collected from Wan and Juju islands in Korea and their methanol extracts were obtained. Heibicidal activities of the methanol extracts were determined by seed bioassay using rapeseed (Brassica napus L.) seedlings. Among eighty-one species, eleven plants were highly herbicidal ($GR_{50}$ < 1,000 ${\mu}g\;g^{-1}$): Abies koreana WILS., Anthemis nobilis L., Callicarpa mollis SIEB. et ZUCC., Cirsium setidens, Euonymus maackii RUPR., Euphorbia jolkini BOISS., Kadsura japonica DUNAL, Paeonia aliflora Pall var. tricocarpa BUNGE, Philadelphus tenuifolius RUPR. et MAXIM., Sapium sebiferum, Vicia angustifolia var. segetilis K. KOCH. Fifty plants were shown moderate herbicidal activity (1,000 ${\mu}g\;g^{-1}$ < $GR_{50}$ < 2,000 ${\mu}g\;g^{-1}$), however, twenty plants were not shown any herbicidal activity.

• The Korean Journal of Pesticide Science
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• v.4 no.2
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• pp.69-71
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• 2000

The herbicidal activities ($pI_{50}$) with alkoxy (RO-) groups on the azomethine nitrogen atom in 5-(2,3-dihydro-2,2-dimethylbenzothiophene-7-yl)-2-(1-(alkoxyimino)butyl)-3-hydroxy-2-cyclohexene-1-one derivatives against various weeds were measured in the flooded and in the paddy conditions. Particularly, i-propoxy subsutuent, 5 of them showed excellent herbicidal activity at a rate of 4kg/ha with pre-emergence against barnyard grass (Echinochloa crus-galli) with good selectivity on rice plant (Oryza sativa). The results of the structure-activity relationships (SAR) analyses are shown that the alkyl subsituents with higher hydrophobicity (logp>0) and electron donating (${\sigma}^*<0$) group as a new substrate rather than alkoxy substituents seems to be contribute to the herbicidal activity with pre-emergence.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.82-82
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• 2018

본 연구는 국내에 자생하는 자원식물들의 살초활성을 조사하여 식물생장억제물질을 활용한 환경친화형 제초제 개발에 요구되는 기초 자료를 확보하기 위해 수행되었다. 국내 자생 식물 101종을 식물체 부위별로 나누어 MeOH로 추출하여 획득된 시료 129점에 대해 돌피(Echinocholoa crus-galli P.B. var. formosensis Ohwi)를 이용한 살초활성 검정을 실시하였다. 시료를 소량의 methanol로 녹여 직경 5.5cm petri dish 상의 Whatman No. 2 여지에 균일하게 흡착시킨 후, fume hood 내에서 용매를 제거하고 1mL의 증류수를 첨가하였다. 돌피 종자를 15립씩 3반복으로 파종하여 $28^{\circ}C$, 5,000lux의 growth chamber에 치상하고, 7일 후 시험구 당 균일하게 자란 10개의 유묘를 선발해 초장 및 근장을 조사하였으며, 살초활성 평가를 위해 대조구 개체의 초장과 근장에 대한 생장억제율을 산출하였다. $1,000{\mu}g/mL$ 농도에서 101종 129점 MeOH 추출물들의 돌피 유묘 뿌리 생장에 대한 억제율을 조사한 결과, 80% 이상을 나타낸 식물 시료는 가죽나무 줄기, 누린내풀 지상부, 단풍취 뿌리, 두릅나무 지상부, 백양꽃 전초, 백양꽃 지하부, 병조희풀 경엽부, 산사나무 잎 가지, 삽주 뿌리, 상사화 전초, 상사화 지하부, 석산 뿌리, 애기송이풀 전초 등 17점이었다. 이들 중 90% 이상 고활성을 나타낸 단풍취 뿌리, 두릅나무 지상부, 백양꽃 전초, 상사화 지하부, 석산 뿌리 유래의 추출물에는 새로운 환경친화형 제초제 개발소재로써 활용할 수 있는 살초활성물질들이 함유되어 있는 것으로 생각된다.

• The Korean Journal of Pesticide Science
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• v.7 no.4
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• pp.248-257
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• 2003

The objective of this experiment was to search plant species with herbicidal activity in Korea. Two hundred native plants were collected and their methanol extracts were obtained. Herbicidal activity of methanol extracts were determined by seed bioassay using canola (Brassica napus L.) seedlings. Six plants such as Staphylea bumalda, Wistaria floribunda, Allium victorialis, Rumex crispus, Chionanthus retusa, and Ulmus parvifolia were highly herbicidal: their $GR_{50}$ values were < $1,000{\mu}g\;g^{-1}$. In addition, seventeen plants such as Galium spurium, Zelkova serrata, Campsis grandiflora, Eucommia ulmoides, Sorbus commixta, Deutzia glabrata, Cercis chinensis, Alnus hirsuta, Zanthoxylum schinifolium, Quercus acutissima, Robinia pseudoacacia, Gleditsia japonica, Kerria japonica, Ligustrum obtusifolium, Thuja orientalis, Chamaecyparis obtusa, and Pulsatilla koreana showed herbicidal activity: their $GR_{50}$ values were between 1,000 and $2,000{\mu}g\;g^{-1}$. However, 177 plants showed no herbicidal activity. Plants with herbicidal activity found in this study could be used for weed management and herbicidal compounds in such herbicidal plants could be used as lead compounds in the development of new herbicides.

• Korean Journal of Weed Science
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• v.30 no.4
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• pp.437-444
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• 2010

This study was conducted to determine the herbicidal activity of allelochemicals and identify herbicidal compounds in bulbs of Lycoris chinensis var. sinuolata. Methanol extract was purified by a series of silica gel flash column chromatography and HPLC. The final HPLC gave two active fractions and an herbicidal compound was obtained. By GC/MS analysis, the herbicidal compound was identified as montanine ($O^2$-methyl pancracine), an isoquinoline alkaloid. Montanine showed 100% of growth inhibition on the shoot and root of barnyardgrass (Echinochloa crus-galli) seedlings at $50\;{\mu}g\;mL^{-1}$ as compared with the control.

• Korean Journal of Weed Science
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• v.30 no.2
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• pp.143-152
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• 2010

Herbicidal characterisitcs of natural product chrysophanic acid were investigated in a greenhouse condition. At early- and middle-stage post-emergence treatments, several grasses and broadleaf weeds appeared to be very susceptible to chrysophanic acid. However, any significant herbicidal activity treated by pre-emergence did not occur at concentration ranges from 31.3 to 1,000 ug $mL^{-1}$. Herbicidal activity of chrysophanic acid estimated by visual injury for large crabgrass was much higher when applied at 7 to 14 days after seeding than at 21 and 28 days after seeding. By post-emergence treatment, chrysophanic acid caused very considerable phytotoxicity on several grasses and broadleaf crops. In herbicidal interaction experiments determined by Colby's method, the effect of chrysophanic acid and caryophyllene oxide tank-mixture showed very high synergistic activity. Although chrysophanic acid did not give any pre-emergence effect, herbicidal spectrum tended to be very wide and strong when treated by post-emergence. These results suggest that chrysophanic acid possesses a possible potential to develop as a natural herbicide.

• Asian Journal of Turfgrass Science
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• v.26 no.1
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• pp.60-66
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• 2012

Crabgrass (Digitaria sanguinalis L.), Dandelion (Taraxacum platycarpum H. DAHLST.), Annual bluegrass (Poa annua L.), Gree kyllinga (Kyllinga brevifolia var.), Red clover (Trifolium pratense L.), Annual lespedeza (Kummerowia striata (Thunb.)Schindl.), Mugwort (Artemisia capillaris Thunb.), Horseweed (Erigeron canadensis L.), Field horsetail (Equisetum arvense L.) are major weeds in turf. In this study, 23 medicinal plant extracts were tested for herbicidal activities against crabgrass and dandelion in the course of major weed in turf. In pot experiment, we implemented pre-emergence application used medicinal plant extracts showed herbicidal activity in petridish experiment. In effect, inhibition rates of germination were 61.0% at Curcuma longa extract and 62.5% at Cnidium officinale extract in crabgrass pot experiment, and 77.8% at Ailanthus altissima extract in dandelion pot experiment.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.32-37
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• 2000

A series of transition metal complexes of 3,6-bis(6'-methyl-2'-pyridyl)pyridazine ($L^{1}$) and 3,6-bis(2'-pyridyl)pyridazine ($L^{2}$) as artificial nuclease, $1{\sim}8$ were synthesized. After determining of X-ray crystal structure, hydrolysis rate constants of phosphates, as DNA model compound and biological activities were confirmed. $L^{2}$-Zn(II) complex, 8 was shown the best hydrolysis rate constant. The $L^{2}$-Ni(II) complex, 5 and $L^{2}$-Co(II) complex, 6 showed the highest herbicidal activity against SCP (Scriptus Juncoids) with excellent tolerance to rice, ORY (Oryzae sativa L.). And the $L^{1}$-Co(II) complex, 2, $L^{1}$-Zn(II) complex, 4 and ligand ($L^{1}$ amp; $L^{2}$) displayed above 90% fungicidal activity against MAG (Magnaporthe grisea).