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| Registros recuperados: 137 | |
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| Long, Marc; Tallec, Kevin; Soudant, Philippe; Lambert, Christophe; Le Grand, Fabienne; Sarthou, Geraldine; Jolley, Dianne; Hegaret, Helene. |
| Harmful microalgal blooms are a threat to aquatic organisms, ecosystems and human health. Toxic dinoflagellates of the genus Alexandrium are known to produce paralytic shellfish toxins and to release bioactive extracellular compounds (BECs) with potent cytotoxic, hemolytic, ichtyotoxic and allelopathic activity. Negative allelochemical interactions refer to the chemicals that are released by the genus Alexandrium and that induce adverse effects on the physiology of co-occurring protists and predators. Releasing BECs gives the donor a competitive advantage that may help to form dense toxic blooms of phytoplankton. However BECs released by Alexandrium minutum are uncharacterized and it is impossible to quantify them using classical chemical methods.... |
| Tipo: Text |
Palavras-chave: Harmful algal bloom; Alexandrium; Allelopathy; Cytotoxicity; PAM fluorometry; Bioassay. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00453/56424/58116.pdf |
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| Borghetti,Fabian; Lima,Elisa Coutinho de; Silva,Lucas de Carvalho Ramos. |
| Most studies conducted to test the allelopathic activity of plant parts have made use of water as solvent. However, the presence of polar, water-soluble substances, such as proteins and carbohydrates, tends to hamper the purification of active compounds. In this study, we present a simple purification procedure that separates the active fraction of the extract from the undesirable substances, thus facilitating the search for active molecules through standard chromatographic methods. Aqueous leaf extracts of three Cerrado species (Caryocar brasiliense, Qualea parviflora and Eugenia dysenterica) were prepared at 5% concentration (w/v) and stored at 4ºC (crude extracts). After 24 h, these solutions were filtered and freeze-dried. The powder obtained was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Cerrado; Freeze-drying; Leaf extract; Purification. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062013000100007 |
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| FORSTER, R.; SAITO, M.L.; MORICONI, W.. |
| Ação alelopática da leguminosa Canavalia ensiformis (feijão de porco) já é praticada em campo semeado com essa leguminosa. Tentativa de esclarecer o modo de ação, levou a testar as partes, raízes, caules, folhas moídas misturadas a terra, plantando-se em seguida os tubérculos de Cyperus rotundus L. em ambiente de laboratório ou em casa de vegetação. Utilizando copos plásticos com capacidade de 160ml, terra argilosa misturada com quantidades diferentes das partes acima citadas, não revelaram qualquer ação sobre a capacidade de brotação dos tubérculos do Cyperus. Utilizando o mesmo método com vagens secas do feijão de porco, e separadamente com sementes, foi possível observar pequena ação da vagem seca, e pronunciada ação das sementes moídas, observou que... |
| Tipo: Resumo em anais de congresso (ALICE) |
Palavras-chave: Alelopatia; Canavalia ensiformis; Cyperus rotundus; Leguminosa; Tiririca; Planta daninha; Planta invasora; Elemento ativo; Bioensaio; Allelopathy; Leguminosae; Weed; Bioassay; Active agent. |
| Ano: 1995 |
URL: http://www.alice.cnptia.embrapa.br/handle/doc/12420 |
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| HUSSAIN,M.I.; QAMAR ABBAS,S.; REIGOSA,M.J.. |
| ABSTRACT: This review covers biological activity of secondary metabolites, coumarin and their derivatives on different organisms (pests, pathogens, weeds), as well as their applications in agriculture as eco-friendly pesticides and weed control agents. Naturally occurring coumarins have shown biological and allelopathic potential on a broad range of organisms. Coumarin inhibits seed germination, root growth, morphology, histology, water uptake, respiration, photosynthesis, cell elongation, cell división and differentiation. Coumarin demonstrate excellent insecticidal potential against eggs, larvae and adult insects. Coumarin showed antifeedent responses in a wide range of memebers from invertebrates to vertebrates. The information provided in this review... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coumarin; Secondary metabolites; Multifunctionality; Herbivory; Allelopathy; Phytotoxicity; Weed control. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100220 |
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| Laabir, Mohamed; Grignon-dubois, Micheline; Masseret, Estelle; Rezzonico, Bernadette; Soteras, Giselle; Rouquette, Manuel; Rieuvilleneuve, Fabien; Cecchi, Philippe. |
| The inhibitory effects of crude extracts of Zostera marina L and Zostera noltii Hornemann on the growth of the toxic red tide dinoflagellate Alexandrium catenella were investigated through bio-assays. Methanolic and aqueous extracts were prepared from fresh and detrital leaves of Z. marina and Z. noltii collected in the Thau lagoon and Arcachon bay (France). All the extracts exhibited significant inhibition of A. catenella growth, whatever the species and without the need of continuous addition of extracts. The effective concentrations (EC50) varied in the range 0.036-0.199 g L-1 for Z. noltii and 0.036-0.239 g L-1 for Z. marina. Methanolic extracts prepared from fresh plant tissues were the most potent, with EC50 of 0.036-0.039 and 0.036-0.045 g L-1, for... |
| Tipo: Text |
Palavras-chave: Growth inhibition; Allelopathy; Alexandrium catenella; Zostera marina; Zostera noltii; Phenolics. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00170/28095/26720.pdf |
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| Long, Marc; Tallec, Kevin; Soudant, Philippe; Le Grand, Fabienne; Donval, Anne; Lambert, Christophe; Sarthou, Geraldine; Jolley, Dianne F.; Hegaret, Helene. |
| Allelochemical interactions are likely to be a contributing factor explaining the success of large blooms of the harmful marine dinoflagellate Alexandrium, however, the physiological mechanisms of allelochemical interactions remain poorly described. Here we investigated the sub-lethal effects (on an hourly scale) of a filtrate containing allelochemicals from Alexandrium minutum on the physiology of the common diatom Chaetoceros muelleri. The filtrate induced deleterious effects to the diatom physiology within only 30 min of exposure. Esterase activity and photosynthesis were drastically inhibited, with up to 34% of the population being metabolically inactive and up to 30% reduction in photosystem II quantum yield when exposed to the filtrate. In addition,... |
| Tipo: Text |
Palavras-chave: Allelopathy; Alexandrium; Metabolism; Photoinhibition; Lipids; Pigments. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00460/57133/59748.pdf |
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| Khaliq,Abdul; Matloob,Amar; Ata Cheema,Zahid; Farooq,Muhammad. |
| Weed suppression is one of the several benefits achieved by soil incorporation of crop residues and such suppression is believed to be allelopathic in nature. The allelopathic potential of different crop residues: viz. sorghum (Sorghum bicolor [L.] Moench), sunflower (Helianthus annuus L.), brassica (Brassica campestris L.) was evaluated in rice (Oryza sativa L.) and jungle rice (Echinochloa colona [L.] Link). Chopped crop residues were soil-incorporated alone and mixed at 6 g kg-1 soil (12 t ha-1) and compared with a control without residues. Soil incorporation of residues substantially delayed germination of jungle rice. The time to start germination, time to 50% emergence, mean emergence time, emergence index, and final germination percentage were all... |
| Tipo: Journal article |
Palavras-chave: Residues; Allelopathy; Sorghum; Sunflower; Brassica; Weed control. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-58392011000300012 |
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| Boiago, Nayara Parisoto; Fortes, Andréa Maria Teixeira; Pilatti, Daiane Maria; Silva, Paulo Sérgio Siberti da. |
| This study aimed to analyse the allelopathic bioactivity of fresh and infused aqueous extracts of Brazilian cherry leaves on the germination of lettuce and the initial development of maize. Brazilian cherry leaves were used to prepare a fresh aqueous extract (200 g L-1) and an infused extract (100 g L-1), which were diluted to concentrations of 0.4, 0.8, 1.2, 1.6 or 2.0% w/v. The variables evaluated in lettuce were the germination rate (GR), germination time index (GTI), germination speed index (GSI) and root length (RL). To determine the effect on the initial development of maize, we measured the shoot (SL) and root (RL) length. The experimental design included a factorial 2 × 5 design (two extracts and five concentrations), in addition to a control... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: 2.03.00.00-0; 2.03.03.00-9 Lactuca sativa; Zea mays; Allelopathy; Allelochemicals; Chemical ecology. Botânica; Fisiologia Vegetal. |
| Ano: 2018 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/40972 |
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| ZOHAIB,A.; ANJUM,S.A.; JABBAR,A.; TABASSUM,T.; ABBAS,T.; NAZIR,U.. |
| ABSTRACT The present study was aimed at determining the allelopathic influence of water extracts at varying concentrations (2.5% and 5% w/v) and residues with varying decomposition periods (0, 15 and 30 days) at 2% (w/w) concentration of four weeds (Trigonella polycerata, Vicia sativa, Lathyrus aphaca, Medicago polymorpha) against rate, synchronization and time of germination, and biomass partitioning of rice through plant and soil bioassays. Germination and biomass partitioning in rice plants were inhibited by extracts and residues. The maximum decrease in energy of germination (88.6%) and increase in time for 50% germination (210.4%) were caused by the L. aphaca extract at 5% concentration as compared to control. Root and shoot, fresh weight (13.6 and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allelopathy; Leguminous weeds; Rice; Germination; Biomass partitioning. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582017000100269 |
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| HASSAN,G.; RASHID,H.U.; AMIN,A.; KHAN,I.A.; SHEHZAD,N.. |
| ABSTRACT: Parthenium hysterophorus being a declared invasive weed worldwide is threatening the biodiversity of Pakistan. To study its allelopathic potential, laboratory and pots based studies were undertaken during July-August and October-November, 2010 in Weed Research Laboratory, Department of Weed Science, The University of Agriculture Peshawar, Khyber Pakhtunkhwa Pakistan. The experiments were conducted to investigate the allelopathic effect of parthenium on crops Triticum aestivum, Cicer arietinum and Brassica campestris, and weeds including Avena fatua, Asphodelus tenuifolius and Lolium rigidum The fresh leaves of P.hysterophorus were dried in shade and grinded. The desired quantity of powder was soaked for 16 hr. in the desired quantity of water... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Parthenium; Allelopathy; Wheat. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100331 |
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| NAEEM,M.; CHEEMA,Z.A.; IHSAN,M.Z.; HUSSAIN,Y.; MAZARI,A.; ABBAS,H.T.. |
| ABSTRACT: Use of synthetic herbicides to control weeds poses serious threats to sustainable agricultural production around the globe. The phytotoxic effect of different plant water extracts (i.e., sorghum, sunflower and mulberry) against weeds has been previously studied; however, their combined effects at different rates are yet to be explored. In this study, mixtures of allelopathic water extracts of sorghum + sunflower and sorghum + sunflower + mulberry were sprayed each at 12, 15, 18 and 21 L ha-1 at 40 and 55 days after sowing in wheat to control wild oats (Avena fatua), little seed canary grass (Phalaris minor), lamb’s quarters (Chenopodium album) and swine cress (Coronopus didymus). A synthetic herbicide Affinity 50 WP (Carfentrazone-ethyl 0.75% +... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Weed management; Allelopathy. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100299 |
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| Registros recuperados: 137 | |
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