• The Korean Journal of Ecology
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• 제23권6호
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• pp.431-434
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• 2000

To examine the allelopathic potentials of Chrysanthemum boreale, aqueous extracts and essential oil of the plant were used in these experiments. Seed germination of the receptor species was inhibited by the aqueous extracts and the inhibitory effect was increased in proportion to the concentration of extracts. In contrast, seedling elongation showed varied results. Achyranthes japonica, Bidens bipinnata, Raphanus sativus var. hortensis for. acanthiformis, Plantago asiatica, Pimpinella brachycarpa and Lactuca sativa were inhibited by increasing concentration of the aqueous extract, while Brassica campestris subsp. napus var. pekinensis and Echinochloa crus-galli were stimulated by the extract. Dry weight was also inhibited proportionally by increasing concentration of the aqueous extract, while some species were stimulated by a lower concentration of the extract. The volatile substances of C. boreale did not affect the seed germination of receptor plants, but seedling elongation and dry weight of some species were inhibited dose-dependently. Root hair development of selected plants was inhibited along with the concentration of essential oil. The above mentioned results, therefore, confirmed that the natural substances from C. boreale had allelopathic potentials to other plants.

• Plant Resources
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• 제7권1호
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• pp.47-53
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• 2004

Several wild plant species are known to contain biologically active substances that are allelopathic to weed species as well as antioxidant to foods. Plant extracts or residues from leaves of 4 species, Achyranthes japonica (speedwell), Cucumis sativus (Cucumber), Trifolium repens (white clover), and Vicia angustifolia (narrowleaf vetch) were bioassayed against Medicago sativa (alfalfa) or Echinochloa crus-galli (barnyard grass) to determine their allelopathic effects, and used for measurement of antioxidant activities. The aqueous extracts applied on filter paper significantly inhibited root growth of alfalfa. Aqueous extracts or residues from V. angustifolia showed the most inhibitory effect on alfalfa or barnyard grass seedling growth and followed by A. japonica and T. repens. Oxidative stability by Rancimat method, antioxidant activity by TBA (2-thiobarbituric acid) method and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity for the ground samples or methanol extracts were the greatest in V. angustifolia, although were less than those of commonly used antioxidants, BHT (butylated hydroxytoluene) and ascorbic acid. These results suggest that the wild plant species had potent allelopathic and antioxidant activities, and that their activities differed depending on plant species.

• 한국유기농업학회지
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• 제21권4호
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• pp.737-752
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• 2013

This study was conducted to evaluate the allelopathic effect of aqueous extract of Ganghwa domestic mugwort (Artemisia spp.) on vegetables and its related allelo-chemicals. When the receptor vegetables, such as Chinese cabbage, lettuce, and red radish, were treated with aqueous extract obtained from Sajabalssuk (A. $sp^*I$), Ssajuarissuk (A. $sp^*II$) or Ssajarissuk (A. $sp^*III$), their germination rate, leaf number, plant height, and root length were restricted with increasing concentration of aqueous extract. Allelopathic effect was the highest in radish, than lettuce and Chinese cabbage in order. The growth of topplant were more inhibited then root growth observing in restriction of plant height, root length, and chlorophyll contents. The plant height, the root length of red radish were 53.3 and 61.2% and their fresh weights were 19.8 and 26.4% compared to those of controls, respectively. A. $sp^*III$ showed the highest allelopathic effect among the donor plants. In HPLC analysis, 7 phenol compounds were identified in A. $sp^*I$ and A. $sp^*II$, and, in A. $sp^*III$, and hydroxybenzoic acid and phenylacetic acid were further identified as allelochemicals. It is considered that their plant growths were variously inhibited by the amounts and types of allelochemicals in aqueous extracts. To increase the productivity of farm land after cultivation of mugwort, these results can be useful to select the following field crops.

• The Korean Journal of Ecology
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• 제24권1호
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• pp.61-66
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• 2001

돼지풀 잎에서 검정된 monoterpenoids는 약 29종이었고, 그 가운데 octene, $\alpha$-ponene, $\beta$-myrcene, 1.3.6-octatrine, endo-borneol, (-)-bomyl acetate의 함량이 높다. Monoterenoids 총 함량은 초봄부터 점차 증가하여 7월에 가장 높았고 그후 감소하였다. 돼지풀 잎에 함유된 휘발성물질은 수용체 유식물의 뿌리와 줄기 생장에 억제효과를 나타내었으며, 생엽량의 증가에 따라 억제효과도 증가하였다. 이에 따른 억제효과 차이의 유의성은 대부분이 P<0.05 수준이었다. 억제효과는 처리식물에 따라 큰 차이가 있었다. 돼지풀 생엽의 채취시기에 따른 유식물 생장 억제효과의 경향성은 대부분의 처리식물에서 7월>6월$\geq$5월 순 이었다.

• 한국잡초학회지
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• 제17권4호
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• pp.375-381
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• 1997

볏단이 있던 곳이나 콤바인 수확한 볏짚이 피복된 곳은 잡초 발생인 생육이 감소하는 현상이 관찰되고 있다. 이는 볏짚에 함유한 allelopathic 물질에 의한 것으로 추정되어 볏짚을 80% 메칠알콜로 추출후 둑새풀로 생물검정, 10종의 표준 유기산이 둑새풀의 생육과 발아에 미치는 영향, 볏짚추출물을 silicagel column 으로 분획후 HPLC, GC/MS로 분석한 결과는 아래와 같았다. 1. HPLC분석에 의하여 볏짚에는 fumaric acid와 4종류의 미확인 유기산이 확인되었다. 2. fumaric acid를 포함한 7종의 유기산은 $10^{-2}$의 농도에서 둑새풀의 생육을 상당히 억제하였고 특히 발아를 100-90% 억제시켰다. 3. 볏짚에 함유한 물질중 억제효과가 가장 큰 것은 GC/MS분석에 의하여 II-4-4Rf 0.5에 함유한 물질로 분자량 253인 치환된 유기산인 신물질로 Octadecanoic acid, 2-oxo-, methyl ester에서 methyl ester가 유리된 물질로 추정되었다.

• The Korean Journal of Ecology
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• 제22권2호
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• pp.85-88
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• 1999

Aqueous and dichloromethane (DCM) extracts of leaves, root bark and inflorescences of Parthenium hysterophorus L. at various concentrations were used to quantify its allelopathic potential against Indigofera tinctoria, Amaranthus viridis, A. gangeticus, Phaseolus mungo (cv. CO 1), Sorghum vulgare (cv. SPT- 462). Pennisetum typhoideus (cv. WCC-75) and Eleusine corocana (cv. CO 1). The aqueous extracts were more inhibitory than the DCM extracts to the germination and seedling growth of the plants studied. The relative rate of inhibition increased in the order of inflorescences. leaves and root bark in the aqueous extracts. whereas DCM root bark and inflorescences extracts were promoted at lower concentrations.

• The Korean Journal of Ecology
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• 제27권5호
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• pp.307-310
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• 2004

It was found that seed germination and seedling growth of selected species were inhibited by phytotoxic substance released from fir trees. The aqueous extracts of leaves caused significant inhibition in the seed germination of the receptor plants, Whereas seed germination of some species was not inhibited in extracts of leaves, but seedling elongation of the receptor plants was also decreased by the aqueous extract. Dry weight growth was slightly increased in lower concentration of the extract, while that was proportionally inhibited by higher concentration of the extracts. Chemical substances of fir trees were shown the biological toxicity. The GC method was employed for analysis of phytotoxic chemicals and sixteen chemical substances were identified such as benzoic, phenylacetic, etc. Also 33 volatile substances were identified from the fir tree. These chemical compounds are assumed the substances related to allelopathic potential of Abies holophylla plant species.

• 한국자원식물학회지
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• 제7권2호
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• pp.115-119
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• 1994

These experiments were conducted to determine the effects of Sorghum allelopathic substances on the callus growh of several weeds and crops. 1. When substances extracted from allelopathic Sorghum(Sorghum bicolor L.) were treated on medium, growth of callus of several weeds and crops were in-hibited. The degree of inhibition differed depending on the genotypes, ranging from 50 to 90% com-pared with that of control. 2. The extracts of above 5% Sorghum inhibited the callus growth of Che-nopodium albun L., Commelina communis L., and .Ammaranthus retroflexus L.and showed in-hibition rate of above 70% in callus growth. These results indicate that we could investigate theallelopaihy effect by using in vitro system. 3. The suitable explant for callus induction fromallelopathic plants was immature embryos, the callus induction rate differed depending on the geno-type, growth regulators and concentrations. In general, the addition of 2, 4-D and NAA onto medium increased the rate and amount of callus.

• The Korean Journal of Ecology
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• 제23권4호
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• pp.323-329
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• 2000

The allelopathic effects of volatile substances from Chamaecyparis obtusa (S. et Z.) Endl. were examined on the germination and seedling growth of some plant species, and on the population growth of some microorganisms. The germination and seedling growth of the receptor plants were suppressed more severely by leaf and fruit essential oils than by those of other parts. Colonial growth of fungi was severely inhibited by essential oils extracted from leaves and fruits. The development of root hairs of the receptor plants was also severely inhibited by the essential oils. The cortical cells at the root tips of Lactuca sativa L. treated with essential oils showed contraction of the cytoplasm, resulting in plasma membranes becoming detached from the cell walls and the cells metamorphosing irregularly. Accumulation of lipid granules inside the contracted cytoplasm and degeneration of mitochondrial cristae were also observed.

• Plant Resources
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• 제8권2호
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• pp.116-121
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• 2005

Compositae plants are known to contain biologically active substances that are allelopathic to agricultural crops as well as weed species. Aqueous or methanol extracts and plant residues from leaves of Xanthium occidentale were assayed against alfalfa (Medicago sativa) to determine its allelopathic effects, and the results showed that the extracts applied onto filter paper significantly inhibited seed germination as well as root growth of alfalfa. Aqueous leaf extracts of $40g\;L^{-1}$ were completely inhibitory on root growth of alfalfa, while root growths of barley (Hordeum vulgare L.) and soybean (Glycine max L.) were less sensitive. Leaf residue incorporation at $100g\;kg^{-1}$ into soil on seedling growth of barnyard grass (Echinochloa crus-galli Beauv. var. oryzicola Ohwi) inhibited both shoot and root fresh weights of barnyard grass by 94 and $96\%$, respectively. Methanol extracts from BuOn and EtOAc fractions of X. occidentale reduced alfalfa root growth more than did those from hexane and water fractions. The results based on bioassay of extracts and residues show that X. occidentale had potent an allelopathic activity against other plant species.