• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.3
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• pp.285-294
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• 1994

Dried top and root extracts of seven different weed species, fresh top and root extracts, and various concentrations of extract (0, 5, 10 and 15%, W/V) and residue rate (0.0, 0.25. 0.5, 0.75 and 1.0%) of velvetleaf (Abutilon theophrasti Medic.) were used to study their allelopathic effects on alfalfa in the laboratory and greenhouse. Top and root aqueous extracts of common lambsquarter (Chenopodium album L.), giant foxtail (Setaria faberii Herrm), redroot pig-weed (Amaranthus retroflexus L), velvetleaf, large crabgrass (Digitaria sanguinalis L), canada thistle (Cirsium arvense L.) and prostrate knotweed (Polygonium aviculare L.) significantly inhibited germination, seedling length, weight, and vigor in alfalfa. Top growth extracts of weeds exhibited greater allelopathic effects than root extracts. Alfalfa test species, WL-320, responded significantly different to the various weed species extracts in terms of allelopathic effect. The regression slopes of various top extracts showed significant variation with respect to germination percentage. Velvetleaf (b=3.69) extracts were the most inhibitory, while large crabgrass (b=2.39) extracts had the least allelopathic effect on alfalfa. When compared the activity of fresh velvetleaf extract to that of dry velvetleaf extract, dry extract was more inhibitory to alfalfa germination and seedling growth. Germination, seedling length and weight of alfalfa were inversely proportional to the concentration of dried velvetleaf extracts. Seedling emergence and survival percentage was inhibited by velvetleaf residue mixture treatment. Also, more of the toxic effects were observed from the dried top extracts, as compared to extracts from fresh top and root. These results demonstrate the allelopathic activity of different weed species extracts and suggest that weeds may affect crop growth and development due to the inhibitory effects of allelochemicals present in weed tissue.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.234-240
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• 1988

Some chloroacetamide derivatives were synthesized from 2,6-dialkyl, aniline 4-chloroaniline, or 3,4-dichloroaniline with alkyl 2-bromopropionate and chloroacetyl chloride and identified by elemental analyses, NMR, and GC/MS spectra as N-(1'-methoxycarbonylethyl)-N-chloroacetyl-2,6-dimethylaniline(ACRI-S-8609), etc. These compounds synthesized were subjected to the test for pre-emergence herbicidal effecs on some grass weeds(Digitaria adscendens, Setaria viridis, Echinochloa crus-galli) and broad leaf weeds(Portulaca oleracea, Amaranthus lividus, Chenopodium album) in pots applied as wettable powder formulations. It was found that N-(1'-ethoxycarbonylethyl)-N-chloroacetyl-2,6-dimethylaniline(ACRI-S-8701) has the highest herbicidal effect on grass weeds, which corresponds to a 95% control effect at an application of 200g a.i/10a. Whereas, some chloroacetamide derivatives derived from 4-chloroaniline or 3,4-dichloroaniline had very weak herbicidal effects on grass and broad leaf weeds.

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.243-248
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• 2015

This study was conducted to investigate the ability for weed control of the shoot extract of sorghum (Sorghum bicolor (L.) Moench) and developing a sustainable weed management in organic farming. When the dried shoot powder was mixed with soil and treated with 2 cm above the soil surface, the germination for Echinochloa crus-galli, Digitaria cilialis, Abutilon theophrasti and Amaranthus retroflexus was inhibited maxium 40%. The growth inhibition of germinated seedlings in the A. theophrasti and A. retroflexus was maxium 30% while it was less than 30% in the E. crus-galli and D. cilialis. Shoot extracts at rates above $25mg\;ml^{-1}$ was effective to inhibit germination of D. cilialis, A. theophrasti and A. retroflexus. The shoot extract concentration required for 50% of germination inhibition was $60mg\;ml^{-1}$ in the E. crus-galli, while it was less than $10mg\;ml^{-1}$ in the D. cilialis, A. theophrasti and A. retroflexus. For the foliar application, 11 adjuvants were tested at 0.5% and DOS70, TM15 and TDE7 were most effective adjuvants for the shoot extracts. DOS70 was most effective and provided up to 60% of weed control efficacy for the tested four weed species. Though herbicidal efficacy of sorghum shoot was not enough to give a proper weed control, it can be expected that long term use of sorghum shoots can provide gradual decrease in weed seeds and weed density.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.4
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• pp.23-40
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• 2012

The vascular plants of major sites in Changwon-si were listed 456 taxa (9.3% of all 4,881 taxa of vascular plants); 112 families, 293 genera, 371 species, 2 subspecies, 66 varieties and 17 forms. The vascular plants of Changwon-cheon were listed 133 taxa, Junam reservoir were listed 90 taxa, Seongju-sa were listed 293 taxa, and Yungji park were listed 164 taxa. Divided into 456 taxa; woody plants were 160 taxa (35.1%) and herbaceous plants were 296 taxa (64.9%). Furthermore, therophytes (Th) were 111 taxa (24.3%), hemicryptophytes (H) were 75 taxa (16.4%), megaphanerophytes (MM) were 63 taxa (13.8%) showed high proportional ratio in life form. Based on the list of rare plants by the Korea Forest Service and Korea National Arboretum, 10 taxa (1.8% of all 571 taxa of rare plants); Aristolochia contorta (LC), Euryale ferox (VU), Melothrua japonica (LC), Utricularia pilosa (CR), Hydrocharis dubia (LC), Carex idzuroei (DD), Acorus calamus var. angustatus (LC), etc. Based on the list of endemic plants by the Korea National Arboretum, 10 taxa (3.0% of all 328 taxa of endemic plants); Salix pseudolasiogyne, Philadelphus incanus, Indigofera koreana, Lespedeza ${\times}$ maritima, Stewartia pseudocamellia, Weigela subsessilis, Carex okamotoi, etc. Based on the list of specific plants by floral region were total 43 taxa (4.0% of all 1,071 taxa of specific plants); 4 taxa (Euryale ferox, Hydrocharis dubia, Carex idzuroei, etc.) in class IV, 9 taxa (Ilex crenata, Acer palmatum, Stewartia pseudocamellia, Melothria japonica, Fatsia japonica, etc.) in class III, 3 taxa (Caltha palustris var. membranacea, Nymphoides indica, etc.) in class II, 26 taxa (Cyrtomium fortunei, Chloranthus japonicus, Quercus variabilis, Ulmus parvifolia, Aphananthe aspera, etc.) in class I. Based on the list of naturalized plants, 48 taxa (Rumex crispus, Chenopodium album var. album, Amaranthus patulus, Phytolacca american, Brassica juncea var. integrifolia, Potentilla paradoxa, Robinia pseudoacacia, Euphorbia maculata, Oenothera odorata, Cuscuta pentagona, Veronica persica, Plantago lanceolata, Diodia teres, Helianthus tuberosus, Dactylis glomerata, etc.), naturalization rate was 10.5% of all 456 taxa of vascular plants and urbanization index was 15.0% of all 321 taxa of naturalized plants. Ecosystem disturbing wild plants were 3 taxa (Rumex acetocella, Solanum carolinense, Ambrosia artemisiifolia).

• Korean Journal of Plant Resources
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• v.17 no.2
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• pp.169-182
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• 2004

The purpose of this study is carried out accurately to grasp the vascular plants in Mt. Bakdal (825 m of sea level), Goesan-gun, Chungcheongbuk-do. In the results of survey from October, 2000 to August, 2001, the vascular plant species in Mt. Bakdal were summarized as 458 taxa; 91 families, 275 genera, 391 species, 62 varieties and 5 forms. The rare plants designated by Korea Forestry Service were six species; Lilium distichum, Iris uniflora var. carisina, Hylomecon hylomeconoides, Viola albida, Scopolia japonicus and Scrophularia koraiensis. And the endemic plants were seventeen species; Melandryum seoulense, Aconitum pseudo-laeve var. erectum, Hylomecon hylomeconoides, Spiraea prunifolia for. simpliciflora, Rubus hongnoensis, Gleditsia japonica var. koraiensis, Lespedeza ${\times}$ tomentella, Vicia venosa var. cuspidata, Vicia venosissima, Tilia taquetii, Ajuga spectabilis, Paulownia coreana, Scrophularia koraiensis, Weigela subsessilis, Lonicera subsessilis, Cirsium setidens and Saussurea seoulensis. The sixteen species were recorded in the surveyed sites as the naturalized plants; Rumex acetocella, Rumex crispus, Fallopia dumetora, Chenopodium glaucum, Amaranthus retroflexus, Robinia pseudo-acacia, Amorpha fruticosa, Trifolium repens, Abutilon avicennae, Hibiscus trionum, Oenothera odorata, Oenothera lamarckiana, Erigeron annuus, Erigeron canadensis, Bidens frondosa and Carduus crispus.

• Korean Journal of Plant Resources
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• v.30 no.4
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• pp.410-426
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• 2017

To identify the flora of the vascular plants in the Anmyeon Island, field surveys were conducted from June, 2015 to August, 2016. Based on the collected specimens, the vascular plants of the Anmyeon Island were summarized as 717 taxa: 119 families, 400 genera, 632 species, 5 subspecies, 73 varieties and 7 formas. Among the 717 identified taxa, 17 rare plants designated by the Koren Forest Service according to the IUCN valuation species were described: 3 taxa of critically endangered species (CR), 1 taxa of endangered species (EN), 6 taxa of least concerned species (LC), 7 taxa of vulnerable species (VU). 99 taxa of floristic regional indicator plants specially designated by Ministry of Environment also were identified. In addition, 6 Korean endemic species such as Forsythia koreana Nakai and Hemerocallis taeanensis S.S.Kang & M.G.Chung, and 91 naturalized plants such as Rumex acetocella L., Amaranthus lividus L. and Diodia teres Walter etc. were described.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.19-28
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• 1987

These experiments were conducted to recognize the germination change in relation to storage period, using 25 kinds of field-collected weed seeds stored under the dry and low temperature ($4{\pm}1^{\circ}C$), and to establish a simple germination induction methods in some kinds of them. No or weak dormancy was observed in Lepidium virginicum, Rumex japonicus, Cirsium japonicum var. ussuriense, Aeschnomene indica and Ludwigia prostrate. The germination of Digltaria sanguinalis, Portulaca oleracea, Amaranthus spp., Echinochloa crux-galli, Polygonum persicaria, Cyperus iria, and Aeschynnmene indica was enhanced by $H_2SO_4$ treatment for 20, 2, 2, 50, 40, 3 or 5 minutes, respectively. Favorable germination in Polygonum persicaria and Echinochloa crus-galli was obtained by soaking in water for 25 days and 50 days, respectively. Moisture treatment for 21 days and 14 days caused the enhancement of germination in Cyperus difformis and Aneilema keisak, respectively. Combination of various treatments in Cyperus iria was most effective when the seeds treated with $H_2SO_4$ for 3 minutes incubated in alternating temp. after soaking in 0.2% $KNO_3$, but their effect on Digitaria sanguinnlis was little.

• Korean Journal of Weed Science
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• v.5 no.1
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• pp.19-23
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• 1985

Soil temperature was higher in clear or blue polyethylene film and bare soil than in black or green polyethylene film and straw mulching. Light transmission was low in black, blue or green colored polyethylene film and straw mulching. Germination of weeds was generally high under clear polyethylene film but black polyethylene film inhibited the germination. Germination of Portulaca oleracea, Setaria viridis and Amaranthus retroflexus increased under blue polyethylene film but inhibition of germination was observed in Erigeron canadensis, Avena fatua, Chenopodium ablum, Digitaria sanguinalis and Echinochloa crusgalli. Green polyethylene film mostly inhibited germination of weeds except A, fatua, C. album and E. canadensis. The greatest number of weeds emerged was obtained in clear polyethylene film, next in bare soil but green or blue polyethylene film inhibited the emergence of weeds. However, no emergence of weeds was observed under black polyethylene film. The highest dry weight of weeds was obtained in clear polyethylene film, next in bare soil, but green or blue polyethylene film and straw mulching caused suppression of weed growth. No weeds were grown under black polyethylene film.

• Korean Journal of Weed Science
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• v.15 no.2
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• pp.121-130
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• 1995

Greenhouse and laboratory studies were conducted to investigate allelopathic potential of some weed species on alfalfa(Medicago sativa L.) germination and seedling growth. In the comparison between top(leaves+stems) and root extracts, top extract exhibited greater allelopathic effects on alfalfa germination than that of root. The various weed species extract differently responded to alfalfa test species, WL-320, in terms of allelopathic effect. Top and root aqueous extracts of lambsquarter(Chenopodium album L.), giant foxtail(Setaria faberii Herrm.), redroot pigweed (Amaranthus retroflexus L.), velvetleaf(Abutilon theophrasti Medic.), crabgrass(Digitaria sanguinalis L.), canada thistle(Cirsium arvense L.) and prostrate knotweed(Polygonium aviculare L.) significantly inhibited germination, seedling length, weight, vigor, and rate of germination of alfalfa. The regression slopes of various top extracts showed that velvetleaf(b=3.69) extracts were the most inhibitory, while large crabgrass(b=2.39) extracts had the least allelopathic effect on alfalfa germination. Germination, seedling length and weight of alfalfa were inversely proportional to the concentration of dried velvetleaf extracts. Also, more of the toxic effects were observed from the dried extracts compared to the fresh extracts. Residue of velvetleaf inhibited significantly alfalfa emergence and survival percentage compared to the control. The emergence and survival percentage of alfalfa were 44%, 57% at 1.0% residue treatment, respectively. When weed residues were mixed with silica sand with incubation time, velvetleaf residue most inhibited alfalfa growth. The degree of inhibition increased as incubation time increased. An incubation for 72h caused the greatest inhibition of alfalfa growth. These results demonstrate the different allelopathic activity of weed species extracts on alfalfa and suggest that weed may affect alfalfa growth and development through the inhibitory effects of allelochemicals present in weed tissue.

• Korean Journal of Organic Agriculture
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• v.23 no.3
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• pp.481-495
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• 2015

The study researched germination of the plants and growth of Fungus according to concentration of aqueous extracts in order to provide basic data for developing natural agricultural resources by using Persicaria longiseta. The seed germination of Amaranthus spinosus was inhibited at 25% P. longiseta extract, while Agrostis stolonifera ssp. palustris was not affected at all concentrations tested. Especially, the seed germination rate and fresh weight of Trifolium incarnatum at 20% P. blumei extract were higher than those of control plot. The early growth of most receptor plant seedlings was promoted at 25% and 50% of P. blumei extracts, but the radicle growth of all receptor plants was significantly inhibited at > 25% of P. longiseta extract. The response of receptor plants to P. longiseta extract was different according to the plant species and the plant parts. The growth of plant pathogenic fungus in PDA medium showed an increasing inhibition tendency with increasing concentrations of P. longiseta extract. Especially, P. longiseta extract showed the greatest antimicrobial activity against Phytophthora infestans, Phythium graminicola, and Pythium venterpoolii. The content of total phenolic compound in P. longiseta was higher in leaves (1082.3 mg/L) but lower in roots (228.6 mg/L) and stems (207.8 mg/L), which is an allelopathic chemical. As these results are summarized, P. longiseta have competitive advantage because they release phenolic compounds with allelopathic effect and affect on germination, growth and fungi growth on underground flora compared to native plants and they have eligibility for natural herbicide and germicide.