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| Author |
Odonne, G.; Herbette, G.; Eparvier, V.; Bourdy, G.; Rojas, R.; Sauvain, M.; Stien, D. |
| Title |
Antileishmanial sesquiterpene lactones from Pseudelephantopus spicatus, a traditional remedy from the Chayahuita Amerindians (Peru). Part III |
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Journal Article |
| Year |
2011 |
Publication |
Journal of Ethnopharmacology |
Abbreviated Journal |
J. Ethnopharmacol. |
| Volume |
137 |
Issue  |
1 |
Pages |
875-879 |
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Asteraceae; Chayahuita; Hirsutinolides; Leishmaniasis; Peru; Pseudelephantopus spicatus; Traditional remedy; 8,13 diacetylpiptocarphol; acetyl 13 o ethylpiptocarphol; amphotericin B; antileishmanial agent; plant extract; Pseudelephantopus spicatus extract; sesquiterpene lactone derivative; unclassified drug; ursolic acid; amastigote; article; biological activity; Ic 50; in vitro study; Leishmania; leishmaniasis; medicinal plant; nonhuman; Peru; Pseudelephantopus spicatus; traditional medicine; Asteraceae; Leishmania amazonensis; Pseudelephantopus spicatus |
| Abstract |
Ethnopharmacological relevance: The study of traditional remedies used by the Chayahuita, an ethnic group from the Peruvian Amazonia, has prompted us to investigate in detail the ethanolic extract of Pseudelephantopus spicatus (Juss. ex Aubl.) C.F. Baker, which has demonstrated strong biological activity towards Leishmania amazonensis. Our goal was to discover the active compound of this plant-based remedy. Materials and methods: A bioguided fractionation of the crude extract was undertaken based on the biological activity recorded against Leishmania amazonensis axenic amastigotes in in vitro bioassays. Results: Three strongly to moderately active compounds were isolated: two hirsutinolides (the 8,13-diacetyl-piptocarphol and the 8-acetyl-13-O-ethyl-piptocarphol) and ursolic acid. IC50 against Leishmania amazonensis axenic amastigotes are respectively 0.2, 0.37 and 0.99 μM (while IC50 of amphotericin B is 0.41 μM). These compounds have never been isolated from this plant species, and germacranolides have never been identified as potential antileishmanial agents. Conclusions: The compounds isolated from Pseudelephantopus spicatus account for the antileishmanial activity of the plant, thus giving support to its use by the Chayahuita in Peru. © 2011 Elsevier Ireland Ltd All rights reserved. |
| Address |
Laboratorio de Investigación y Desarrollo, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia, Avenida Honorio Delgado 430, San Martin de Porres, Lima, Peru |
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03788741 (Issn) |
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Export Date: 21 October 2011; Source: Scopus; Coden: Joetd; doi: 10.1016/j.jep.2011.07.008; Language of Original Document: English; Correspondence Address: Odonne, G.; Bureau du CNRS en Guyane, CNRS – UPS 2561, 2 Avenue Gustave Charlery, 97300 Cayenne, France; email: guillaume.odonne@gmail.com; Chemicals/CAS: amphotericin B, 1397-89-3, 30652-87-0; ursolic acid, 77-52-1 |
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EcoFoG @ webmaster @ |
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350 |
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Dejean, A.; Delabie, J.H.C.; Cerdan, P.; Gibernau, M.; Corbara, B. |
| Title |
Are myrmecophytes always better protected against herbivores than other plants? |
Type |
Journal Article |
| Year |
2006 |
Publication |
Biological Journal of the Linnean Society |
Abbreviated Journal |
Biol. J. Linn. Soc. |
| Volume |
89 |
Issue |
1 |
Pages |
91-98 |
| Keywords |
Ant-plant mutualism; Azteca; Maieta; Myrmecophytes; Plant protection; Tococa; ant; defoliation; field method; mutualism; myrmecophyte; plant-herbivore interaction; Azteca; Azteca bequaerti; Clidemia; Crematogaster laevis; Formicidae; Maieta; Maieta guianensis; Pheidole minutula; Tococa; Tococa guianensis |
| Abstract |
The present field study compared the degree of defoliation of three Guianian melastome, two myrmecophytes (i.e. plants sheltering ants in hollow structures) and Clidemia sp., a nonmyrmecophytic plant serving as a control. Maieta guianensis Aubl. hosted mostly Pheidole minutula Mayr whatever the area, whereas Tococa guianensis Aubl. hosted mostly Azteca bequaerti Wheeler along streams and Crematogaster laevis Mayr or Azteca sp. 1 in the understory where it never blossomed. Only Tococa, when sheltering A. bequaerti in what can be considered as a truly mutualistic relationship, showed significantly less defoliation than control plants. In the other associations, the difference was not significant, but P. minutula is mutualistic with Maieta because it furnishes some protection (exclusion experiments) plus nutrients (previous studies). When devoid of ants, Tococa showed significantly greater defoliation than control plants; therefore, it was deduced that Tococa probably lacks certain antidefoliator metabolites that control plants possess (both Tococa and control plants are protected by ground-nesting, plant-foraging ants, which is termed 'general myrmecological protection'). Consequently, plant-ants other than A. bequaerti probably also protect Tococa slightly, thus compensating for this deficiency and permitting it to live in the understory until treefall gaps provide the conditions necessary for seed production. © 2006 The Linnean Society of London. |
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Laboratoire de Psychologie Sociale de la Cognition (UMR CNRS 6024), Université Blaise Pascal, 34 avenue Carnot, 63037 Clermont-Ferrand Cedex, France |
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00244066 (Issn) |
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Cited By (since 1996): 9; Export Date: 22 October 2011; Source: Scopus; Coden: Bjlsb; doi: 10.1111/j.1095-8312.2006.00660.x; Language of Original Document: English; Correspondence Address: Dejean, A.; Laboratoire d'Evolution et Diversité Biologique (UMR CNRS 5174), Université Toulouse III, Bâtiment 4R3, 118 route de Narbonne, 31062 Toulouse Cedex, France; email: dejean@cict.fr |
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EcoFoG @ webmaster @ |
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355 |
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Porth, I.; Scotti-Saintagne, C.; Barreneche, T.; Kremer, A.; Burg, K. |
| Title |
Linkage mapping of osmotic stress induced genes of oak |
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Journal Article |
| Year |
2005 |
Publication |
Tree Genetics and Genomes |
Abbreviated Journal |
Tree Genet. Genomes |
| Volume |
1 |
Issue |
1 |
Pages |
31-40 |
| Keywords |
Est; Linkage map; Oak; Osmotic stress; Quercus ssp.; Fagaceae; Quercus; Quercus petraea; Quercus robur |
| Abstract |
Water stress affecting long-lived trees is an important challenge in forestry. Due to global climate change, forest trees will be threatened by extreme conditions like flooding or drought. It is necessary to understand differences in stress tolerance within certain species and to investigate putative relations on genomic level. In this study, osmotic stress induced genes of Quercus ssp. were positioned on two genetic linkage maps of oak. An intra-specific cross 3P*A4 of Quercus robur consisting of 88 offspring and an inter-specific cross 11P*QS29 of Q. robur and Q. petraea comprising 72 full-sibs were analyzed for the inheritance of 14 loci represented by 34 individual single nucleotide polymorphisms. Seven genes in the intra-cross, as well as other six genes in the inter-cross could be mapped and one gene could not be localised due to the severe distortion of the segregation. The collection of expressed sequences involved ribosomal proteins, members of the oxylase/oxygenase gene family, betaine aldehyde dehydrogenase, Dc3 promoter-binding factor, a putative member of the nodulin family, glutathione-S-transferase and proteins with unknown functions. In the inter-cross, two linked markers exhibited 89% deficiency of heterozygosity. Thirteen genes were positioned on ten different oak chromosomes and can serve as orthologous markers in comparative mapping studies within Fagaceae. © Springer-Verlag 2005. |
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INRA BIOGECO, 69 Route d'Arcachon, 33612 Cestas, France |
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16142942 (Issn) |
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Cited By (since 1996): 9; Export Date: 22 October 2011; Source: Scopus; doi: 10.1007/s11295-005-0005-1; Language of Original Document: English; Correspondence Address: Burg, K.; Division of Biogenetics and Natural Resources, Austrian Research Center Seibersdorf, 2444 Seibersdorf, Austria; email: kornel.burg@arcs.ac.at |
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EcoFoG @ webmaster @ |
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357 |
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Paine, C.E.T.; Norden, N.; Chave, J.; Forget, P.-M.; Fortunel, C.; Dexter, K.G.; Baraloto, C. |
| Title |
Phylogenetic density dependence and environmental filtering predict seedling mortality in a tropical forest |
Type |
Journal Article |
| Year |
2012 |
Publication |
Ecology Letters |
Abbreviated Journal |
Ecol. Lett. |
| Volume |
15 |
Issue |
1 |
Pages |
34-41 |
| Keywords |
Community assembly; Density dependence; French Guiana; Generalised linear mixed models; Janzen-Connell hypothesis; Seedling recruitment; Species coexistence; Survival |
| Abstract |
Negative density dependence (NDD) and environmental filtering (EF) shape community assembly, but their relative importance is poorly understood. Recent studies have shown that seedling's mortality risk is positively related to the phylogenetic relatedness of neighbours. However, natural enemies, whose depredations often cause NDD, respond to functional traits of hosts rather than phylogenetic relatedness per se. To understand the roles of NDD and EF in community assembly, we assessed the effects on seedling mortality of functional similarity, phylogenetic relatedness and stem density of neighbouring seedlings and adults in a species-rich tropical forest. Mortality risks increased for common species when their functional traits departed substantially from the neighbourhood mean, and for all species when surrounded by close relatives. This indicates that NDD affects community assembly more broadly than does EF, and leads to the tentative conclusion that natural enemies respond to phylogenetically correlated traits. Our results affirm the prominence of NDD in structuring species-rich communities. © 2011 Blackwell Publishing Ltd/CNRS. |
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Department of Biology, University of Florida, Gainesville, FL 32611, United States |
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1461023x (Issn) |
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Export Date: 13 December 2011; Source: Scopus; Coden: Eclef; doi: 10.1111/j.1461-0248.2011.01705.x; Language of Original Document: English; Correspondence Address: Paine, C.E.T.; Institut für Evolutionsbiologie und Umweltwissenschaften, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland; email: timothy.paine@ieu.uzh.ch |
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EcoFoG @ webmaster @ |
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373 |
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Malé, P.-J.G.; Leroy, C.; Dejean, A.; Quilichini, A.; Orivel, J. |
| Title |
An ant symbiont directly and indirectly limits its host plant's reproductive success |
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Journal Article |
| Year |
2012 |
Publication |
Evolutionary Ecology |
Abbreviated Journal |
Evol. Ecol. |
| Volume |
26 |
Issue |
1 |
Pages |
55-63 |
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Cheater; Evolutionary conflict; Mutualism breakdown; Myrmecophyte; Pollination |
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In theory, mutualisms are intrinsically unstable, and the search for the maximum profit at the minimum cost should lead every mutualist to become a parasite. From an empirical point of view, mutualisms are ubiquitous and of major importance to ecosystems, suggesting the existence of mechanisms that enhance the maintenance of such relationships. We focused on the obligatory myrmecophytic association between the Neotropical plant Hirtella physophora (Chrysobalanaceae) and the ant Allomerus decemarticulatus (Myrmicinae). The plant shelters the ants in leaf pouches in exchange for protection from phytophagous insects. We experimentally demonstrated that the ants partially castrate their host plant by destroying almost two-thirds of its floral buds. The ants also impede pollination through their presence and interactions with pollinators. These results reveal that ant activity negatively affects the plant's reproduction both directly and indirectly. This dual negative effect does not result in the complete castration of the plant. We also highlight major limitations to plant reproduction due to the spontaneous abscission of flowers and to the limited quantity and/or poor quality of the pollen. These limitations must not be overlooked since they can alter the outcome of the association of H. physophora with its ant partner. We therefore conclude that the evolutionary fate of the relationship depends on both ant castration intensity and obstacles to plant fertilization not related to the presence of ants. © 2011 Springer Science+Business Media B.V. |
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Jardin Botanique Henri Gaussen, 39 Allées Jules Guesde, 31062 Toulouse, France |
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02697653 (Issn) |
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Export Date: 2 January 2012; Source: Scopus; Coden: Evece; doi: 10.1007/s10682-011-9485-7; Language of Original Document: English; Correspondence Address: Malé, P.-J. G.; CNRS, EDB (Laboratoire Evolution et Diversité Biologique), UMR 5174, Université Paul Sabatier, 118 Route de Narbonne, 31062 Toulouse Cedex 9, France; email: pjmale@cict.fr |
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no |
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EcoFoG @ webmaster @ |
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377 |
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Leroy, C.; Corbara, B.; Pélozuelo, L.; Carrias, J.-F.; Dejean, A.; Céréghino, R. |
| Title |
Ant species identity mediates reproductive traits and allocation in an ant-garden bromeliad |
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Journal Article |
| Year |
2012 |
Publication |
Annals of Botany |
Abbreviated Journal |
Ann. Bot. |
| Volume |
109 |
Issue |
1 |
Pages |
145-152 |
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δ15N; Aechmea mertensii; Bromeliaceae; bromeliad; Camponotus femoratus; floral traits; fruit-set; mutualistic ants; Pachycondyla goeldii; reproductive allocation; stable isotopes |
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•Background and Aims: Determining the sources of variation in floral morphology is crucial to understanding the mechanisms underlying Angiosperm evolution. The selection of floral and reproductive traits is influenced by the plants abiotic environment, florivores and pollinators. However, evidence that variations in floral traits result from mutualistic interactions with insects other than pollinators is lacking in the published literature and has rarely been investigated. We aimed to determine whether the association with either Camponotus femoratus or Pachycondyla goeldii (both involved in seed dispersal and plant protection) mediates the reproductive traits and allocation of Aechmea mertensii, an obligatory ant-garden tank-bromeliad, differently.•Methods: Floral and reproductive traits were compared between the two A. mertensii ant-gardens. The nitrogen flux from the ants to the bromeliads was investigated through experimental enrichments with stable isotopes (15N).•Key Results: Camponotus femoratus-associated bromeliads produced inflorescences up to four times longer than did P. goeldii-associated bromeliads. Also, the numbers of flowers and fruits were close to four times higher, and the number of seeds and their mass per fruit were close to 1·5 times higher in C. femoratus than in P. goeldii-associated bromeliads. Furthermore, the 15N-enrichment experiment showed that C. femoratus-associated bromeliads received more nitrogen from ants than did P. goeldii-associated bromeliads, with subsequent positive repercussions on floral development. Greater benefits were conferred to A. mertensii by the association with C. femoratus compared with P. goeldii ants.•Conclusions: We show for the first time that mutualistic associations with ants can result in an enhanced reproductive allocation for the bromeliad A. mertensii. Nevertheless, the strength and direction of the selection of floral and fruit traits change based on the ant species and were not related to light exposure. The different activities and ecological preferences of the ants may play a contrasting role in shaping plant evolution and speciation. © The Author 2011. |
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Université de Toulouse, 118 route de Narbonne, F-31062 Toulouse Cedex 9, France |
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03057364 (Issn) |
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Export Date: 12 January 2012; Source: Scopus; Coden: Anboa; doi: 10.1093/aob/mcr253; Language of Original Document: English; Correspondence Address: Leroy, C.; CNRS, UMR Ecologie des Forêts de Guyane (UMR-CNRS 8172), Campus Agronomique, F-97379 Kourou Cedex, France; email: celine.leroy@ecofog.gf |
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EcoFoG @ webmaster @ |
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378 |
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Cachet, N.; Ho-A-Kwie, F.; Rivaud, M.; Houel, E.; Deharo, E.; Bourdy, G.; Jullian, V. |
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Picrasin K, a new quassinoid from Quassia amara L. (Simaroubaceae) |
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Journal Article |
| Year |
2012 |
Publication |
Phytochemistry Letters |
Abbreviated Journal |
Phytochem. Lett. |
| Volume |
5 |
Issue |
1 |
Pages |
162-164 |
| Keywords |
Malaria; P. falciparum; Quassia amara; Quassinoids; Simaroubaceae |
| Abstract |
A new quassinoid Picrasin K 1 was isolated from a decoction made of Quassia amara leaves, traditionally used in French Guyana to treat malaria. The structure and relative stereochemistry of 1 was determined through extensive NMR analysis. Picrasin K showed a low activity against Plasmodium falciparum in vitro (IC 50 = 8 μM), and a similar low activity on human cancerous cells line (IC 50 = 7 μM on MCF-7 cells line). © 2011 Phytochemical Society of Europe. Published by Elsevier B.V. All rights reserved. |
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CNRS, UMR Ecofog, Université des Antilles et de la Guyane, Cayenne, France |
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18743900 (Issn) |
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Export Date: 8 March 2012; Source: Scopus; doi: 10.1016/j.phytol.2011.12.001; Language of Original Document: English; Correspondence Address: Jullian, V.; UMR-152 Pharma-Dev, IRD, Université Paul Sabatier Toulouse 3, 31062 Toulouse, France; email: jullian@cict.fr |
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EcoFoG @ webmaster @ |
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382 |
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Revel, N.; Alvarez, N.; Gibernau, M.; Espíndola, A. |
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Investigating the relationship between pollination strategies and the size-advantage model in zoophilous plants using the reproductive biology of Arum cylindraceum and other European Arum species as case studies |
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Journal Article |
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2012 |
Publication |
Arthropod-Plant Interactions |
Abbreviated Journal |
Arthropod-Plant Interact. |
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6 |
Issue |
1 |
Pages |
35-44 |
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Araceae; Flower evolution; Plant-insect interactions; Reproductive strategy; Sex allocation |
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The size-advantage model (SAM) explains the temporal variation of energetic investment on reproductive structures (i. e. male and female gametes and reproductive organs) in long-lived hermaphroditic plants and animals. It proposes that an increase in the resources available to an organism induces a higher relative investment on the most energetically costly sexual structures. In plants, pollination interactions are known to play an important role in the evolution of floral features. Because the SAM directly concerns flower characters, pollinators are expected to have a strong influence on the application of the model. This hypothesis, however, has never been tested. Here, we investigate whether the identity and diversity of pollinators can be used as a proxy to predict the application of the SAM in exclusive zoophilous plants. We present a new approach to unravel the dynamics of the model and test it on several widespread Arum (Araceae) species. By identifying the species composition, abundance and spatial variation of arthropods trapped in inflorescences, we show that some species (i. e. A. cylindraceum and A. italicum) display a generalist reproductive strategy, relying on the exploitation of a low number of dipterans, in contrast to the pattern seen in the specialist A. maculatum (pollinated specifically by two fly species only). Based on the model presented here, the application of the SAM is predicted for the first two and not expected in the latter species, those predictions being further confirmed by allometric measures. We here demonstrate that while an increase in the female zone occurs in larger inflorescences of generalist species, this does not happen in species demonstrating specific pollinators. This is the first time that this theory is both proposed and empirically tested in zoophilous plants. Its overall biological importance is discussed through its application in other non-Arum systems. © 2011 Springer Science+Business Media B.V. |
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CNRS-UMR 8172 Ecologie des Forêts de Guyane, BP 709, 97387 Kourou, France |
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18728855 (Issn) |
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Export Date: 21 March 2012; Source: Scopus; doi: 10.1007/s11829-011-9164-1; Language of Original Document: English; Correspondence Address: Espíndola, A.; Department of Ecology and Evolution, University of Lausanne, Biophore Building, 1015 Lausanne, Switzerland; email: MariaAnahi.Espindola@unil.ch |
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EcoFoG @ webmaster @ |
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384 |
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Maia, A.C.D.; Gibernau, M.; Carvalho, A.T.; Gonçalves, E.G.; Schlindwein, C. |
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The cowl does not make the monk: Scarab beetle pollination of the Neotropical aroid Taccarum ulei (Araceae: Spathicarpeae) |
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Journal Article |
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2013 |
Publication |
Biological Journal of the Linnean Society |
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108 |
Issue |
1 |
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22-34 |
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Flower predation; Nocturnal pollinators; Pollination syndromes; Scarabaeidae; Thermogenesis |
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Taccarum ulei (Araceae, Spathicarpeae) is a seasonal geophytic aroid, native to north-eastern Brazil, that flowers during two months of the rainy season. Patterns of floral thermogenesis, pollination biology, and floral traits associated with pollination syndromes were studied and compared with those of other Araceae. Two species of cyclocephaline scarabs (Scarabaeidae, Cyclocephalini) were recognized as effective pollinators: Cyclocephala celata and Cyclocephala cearae. Larvae of an unidentified species of fruit fly (Melanolomaspp., Richardiidae, Diptera) were also frequently observed in inflorescences at various maturation stages, feeding on the connectives of male florets and fruits, and thus lowering the reproductive success of individual plants. Beetles were attracted by odoriferous inflorescences in the early evening of the first day of anthesis, during the female phase. The emission of attractive volatiles was coupled with intense thermogenic activity in the entire spadix, unlike other aroids in which only certain zones of the spadix heat up. Pollen release, which marks the beginning of the male phase on the subsequent evening, was not related to floral thermogenesis. Comparative multivariate analysis of the floral traits of T.ulei points to a beetle-pollinated aroid, although some of the observed traits of the species are not common to other taxa sharing this pollination strategy. Such incongruence might be explained by the evolutionary history of the tribe Spathicarpeae and potential pollinator shifts. © 2012 The Linnean Society of London. |
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Departamento de Botânica, Universidade Federal de Minas Gerais, Belo Horizonte, 31270-901, Brazil |
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Export Date: 3 January 2013; Source: Scopus |
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EcoFoG @ webmaster @ |
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453 |
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Brémaud, I.; Ruelle, J.; Thibaut, A.; Thibaut, B. |
| Title |
Changes in viscoelastic vibrational properties between compression and normal wood: Roles of microfibril angle and of lignin |
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Journal Article |
| Year |
2013 |
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Holzforschung |
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| Volume |
67 |
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1 |
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75-85 |
| Keywords |
Compression wood (CW); Damping coefficient; Ft-Ir; Internal friction; Lignin; Microfibril angle (MFA); Picea abies; Pinus pinaster; Pinus sylvestris; Specific dynamic modulus of elasticity; Viscoelastic vibrational properties |
| Abstract |
This study aims at better understanding the respective influences of specific gravity (γ ), microfibril angle (MFA), and cell wall matrix polymers on viscoelastic vibrational properties of wood in the axial direction. The wide variations of properties between normal wood (NW) and compression wood (CW) are in focus. Three young bent trees (Picea abies, Pinus sylvestris and Pinus pinaster ), which recovered verticality, were sampled. Several observed differences between NW and CW were highly significant in terms of anatomical, physical (γ, shrinkage, CIE Lab colorimetry), mechanical (compressive strength), and vibrational properties. The specific dynamic modulus of elasticity (E′/γ) decreases with increasing MFA, and Young's modulus (E′) can be satisfactorily explained by γ and MFA. Apparently, the type of the cell wall polymer matrix is not influential in this regard. The damping coefficient (tan δ) does not depend solely on the MFA of NW and CW. The tanδ-E′/γ relationship evidences that, at equivalent E′/γ, the tan δ of CW is approximately 34% lower than that of NW. This observation is ascribed to the more condensed nature of CW lignins, and this is discussed in the context of previous findings in other hygrothermal and time/frequency domains. It is proposed that the lignin structure and the amount and type of extractives, which are both different in various species, are partly responsible for taxonomy-related damping characteristics. Copyright © by Walter de Gruyter • Berlin • Boston. |
| Address |
Wood Laboratory, Empa-Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, CH-8600 Dübendorf, Switzerland |
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Export Date: 25 February 2013; Source: Scopus |
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EcoFoG @ webmaster @ |
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471 |
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