• Korean Journal of Weed Science
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• v.9 no.1
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• pp.76-79
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• 1989

As a result of screening search for biologically active substances to weed seeds among higher plants, MeOH extract from Rhathiolepis ovata Briat was found to inhibit germination of test weeds considerably. In the course of purifying the active substances, pinoresinol which showed very similar behavior with the active fraction on various chromatographies, was isolated from the same source, spectrally identified and bioassayed. Pinoresinol exhibited germination inhibitory activity against the common purslane (Portulaca oleracea L.) only ; the inhibitory effect was about 55% at concentration of 5 mg/ml.

• Korean Journal of Weed Science
• /
• v.9 no.1
• /
• pp.69-75
• /
• 1989

To search germination inhibitors in higher plants, first of all, some experiments containing selection of test weed seeds and effects of solvents and surfactants for bioassay establishment were conducted. Then MeOH-extracts of 45 plants were assayed for germination inhibition activities against Echinochloa crus-galli (L.) Beauv, Digitaria sanguinalis (L.) Scop., Cyperus iria L., Portulaca oleracea L. and Oenothera lamarckiana Ser. seeds. Among them extracts from Rhathiolepis ovata Briat and Picea abies (L.) Karst showed strong inhibitory effect (60-90% inhibition) on the germination of tested weed seeds at 5000 ppm. On the other hand, the extract from Youngia sonchifolia Max stimulated the germination and growth of tested weeds.