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| Author | Leroy, C.; Jauneau, A.; Quilichini, A.; Dejean, A.; Orivel, J. | ||||
Title  |
Comparison between the anatomical and morphological structure of leaf blades and foliar domatia in the ant-plant Hirtella physophora (Chrysobalanaceae) | Type | Journal Article | ||
| Year | 2008 | Publication | Annals of Botany | Abbreviated Journal | Ann. Bot. |
| Volume | 101 | Issue | 4 | Pages | 501-507 |
| Keywords | anatomy; ant-plant mutualism; Chrysobalanaceae; extra-floral nectaries; French Guiana; Hirtella physophora; secondary domatia | ||||
| Abstract | Background and Aims Myrmecophytes, or ant-plants, are characterized by their ability to shelter colonies of some ant species in hollow structures, or ant-domatia, that are often formed by hypertrophy of the internal tissue at specific locations (i.e. trunk, branches, thorns and leaf pouches). In Hirtella physophora (Chrysobalanaceae), the focal species of this study, the ant-domatia consist of leaf pouches formed when the leaf rolls over onto itself to create two spheres at the base of the blade. Methods The morphological and anatomical changes through which foliar ant-domatia developed from the laminas are studied for the first time by using fresh and fixed mature leaves from the same H. physophora individuals. Key results Ant-domatia were characterized by larger extra-floral nectaries, longer stomatal apertures and lower stomatal density. The anatomical structure of the domatia differed in the parenchymatous tissue where palisade and spongy parenchyma were indistinct; chloroplast density was lower and lignified sclerenchymal fibres were more numerous compared with the lamina. In addition, the domatia were thicker than the lamina, largely because the parenchymatous and epidermal cells were enlarged. Conclusion Herein, the morphological and anatomical changes that permit foliar ant-domatia to be defined as a specialized leaf structure are highlighted. Similarities as well as structural modifications in the foliar ant-domatia compared with the lamina are discussed from botanical, functional and mutualistic points of view. These results are also important to understanding the reciprocal evolutionary changes in traits and, thus, the coevolutionary processes occurring in insect-plant mutualisms. | ||||
| Address | [Leroy, Celine; Quilichini, Angelique; Dejean, Alain; Orivel, Jerome] Univ Toulouse 3, CNRS, UMR 5174, Lab Evolut & Diversite Biol, F-31062 Toulouse 9, France, Email: orivel@cict.fr | ||||
| Corporate Author | Thesis | ||||
| Publisher | OXFORD UNIV PRESS | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0305-7364 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000253489700003 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 212 | ||
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| Author | Leroy, C.; Jauneau, A.; Quilichini, A.; Dejean, A.; Orivel, J. | ||||
| Title |
Comparative Structure and Ontogeny of the Foliar Domatia in Three Neotropical Myrmecophytes | Type | Journal Article | ||
| Year | 2010 | Publication | American Journal of Botany | Abbreviated Journal | Am. J. Bot. |
| Volume | 97 | Issue | 4 | Pages | 557-565 |
| Keywords | anatomy; ant-plant mutualism; Chrysobalanaceae; domatia; French Guiana; Hirtella physophora; Maieta guianensis; Melastomataceae; myrmecophyte; ontogeny; Tococa guianensis | ||||
| Abstract | The origin and timing of the appearance of leaf domatia during the ontogeny of plants are important evolutionary traits driving the maintenance of ant-plant associations. In this study conducted in French Guiana on Hirtella physophora, Maieta guianensis, and Tococa guianensis, we focused on the formation and development of leaf domatia having different morphological origins. We modeled the timing of the onset of these domatia, then compared their morpho-anatomical structure. Although the ontogenetic development of the domatia differed between species, they developed very early in the plant's ontogeny so that we did not note differences in the timing of the onset of these domatia. For H. physophora seedlings, a transitional leaf forms before the appearance of fully developed domatia, whereas in M. guianensis and T. guianensis the domatia forms abruptly without transitional leaves. Moreover, in all cases, the morpho-anatomical structure of the domatia differed considerably from the lamina. All three species had similar morpho-anatomical characteristics for the domatia, indicating a convergence in their structural and functional characteristics. This convergence between taxonomically distant plant species bearing domatia having different morphological origins could be interpreted as a product of the plant's evolution toward the morphology and anatomy most likely to maximize ant recruitment and long-term residence. | ||||
| Address | [Leroy, Celine; Dejean, Alain] CNRS, Unite Mixte Rech Ecol Forets Guyane, F-97379 Kourou, France, Email: Celine.Leroy@ecofog.gf | ||||
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| Publisher | BOTANICAL SOC AMER INC | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0002-9122 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000276045500003 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 65 | ||
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| Author | Cottet, K.; Genta-Jouve, G.; Fromentin, Y.; Odonne, G.; Duplais, C.; Laprévote, O.; Michel, S.; Lallemand, M.-C. | ||||
| Title |
Comparative LC-MS-based metabolite profiling of the ancient tropical rainforest tree Symphonia globulifera | Type | Journal Article | ||
| Year | 2014 | Publication | Phytochemistry | Abbreviated Journal | Phytochemistry |
| Volume | 108 | Issue | Pages | 102-108 | |
| Keywords | Kendrick mass defect; Lc-Ms; Plant organs; Symphonia globulifera; Untargeted metabolomics; Symphonia globulifera | ||||
| Abstract | In the last few years, several phytochemical studies have been undertaken on the tropical tree Symphonia globulifera leading to the isolation and characterisation of several compounds exhibiting antiparasitic activities against Plasmodium falciparum, Trypanosoma brucei and Leishmania donovani. The comparative LC-MS based metabolite profiling study conducted on the tree led to the identification of compounds originating from specific tissues. The results showed that renewable organs/tissues can be used as the starting material for the production of polycyclic poly-prenylated-acylphloroglucinols, therefore reducing impacts on biodiversity. This study also underlined the lack of knowledge on the secondary metabolites produced by S. globulifera since only a small number of the total detected features were putatively identified using the database of known compounds for the species. | ||||
| Address | Laboratoire de Chimie et Toxicologie Analytique et Cellulaire, UMR 8638, Université Paris Descartes Sorbonne Paris Cité, 4 Avenue de l'ObservatoireParis, France | ||||
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| Publisher | Elsevier Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 00319422 (Issn) | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Export Date: 2 December 2014; Coden: Pytca; Correspondence Address: Genta-Jouve, G.; Laboratoire de Pharmacognosie, UMR 8638, Université Paris Descartes Sorbonne Paris Cité, 4 Avenue de l'Observatoire, France | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 569 | ||
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| Author | Pierrejean, I.; Mehinto, T.; Beauchene, J. | ||||
| Title |
Comparative Analysis of Three Different Methods Used to Determine the Elastic Modulus for a Choice of Tropical Guianese Wood Species | Type | Journal Article | ||
| Year | 2017 | Publication | Pro Ligno | Abbreviated Journal | |
| Volume | 13 | Issue | 1 | Pages | 3-17 |
| Keywords | density; modulus of elasticity; static and dynamic tests; tropical woods | ||||
| Abstract | This study compares variability in the longitudinal Modulus of Elasticity (MOE) values, measured by three different methods, for eight tropical wood species covering a wide range of densities, a property that has been little described in the literature for some of the species studied. The modulus of elasticity in wood species is one of the main mechanical properties measured to characterize wood materials. However, this property is seldom described for the tropical wood species studied here, and the method used is often variable. The aim is to answer the following questions. In the methods used, what are the main variability factors which influence modulus measurement? Is the modulus different with regard to the solicitation direction (radial or tangential)? Which relationship exists between modulus and density for these species?
The samples were subjected to the four-point bending test, then to the free vibration test and to the forced-vibration test (which allows tests on small samples).The samples were subjected to stress in radial and tangential directions. The modulus values obtained by the different methods were well correlated for most of the species. The relationship between modulus and density was very good at inter-specific level because sampling covered a wide range of densities. But this relationship was not so good for each of the species sampled. This kind of test was not appropriate for detecting differences in behavior between the two directions of solicitation for these species. The main features of the three methods were summarized, highlighting the advantages of each for the species studied. |
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 753 | ||
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| Author | Birer, C.; Tysklind, N.; Zinger, L.; Duplais, C. | ||||
| Title |
Comparative analysis of DNA extraction methods to study the body surface microbiota of insects: A case study with ant cuticular bacteria | Type | Journal Article | ||
| Year | 2017 | Publication | Molecular Ecology Resources | Abbreviated Journal | Mol Ecol Resour |
| Volume | 17 | Issue | 6 | Pages | e34-e45 |
| Keywords | 16S rRNA; bacterial communities; cuticular microbiome; insect cuticle; metabarcoding | ||||
| Abstract | High-throughput sequencing of the 16S rRNA gene has considerably helped revealing the essential role of bacteria living on insect cuticles in the ecophysiology and behaviour of their hosts. However, our understanding of host-cuticular microbiota feedbacks remains hampered by the difficulties of working with low bacterial DNA quantities as with individual insect cuticle samples, which are more prone to molecular biases and contaminations. Herein, we conducted a methodological benchmark on the cuticular bacterial loads retrieved from two Neotropical ant species of different body size and ecology: Atta cephalotes (~15 mm) and Pseudomyrmex penetrator (~5 mm). We evaluated the richness and composition of the cuticular microbiota, as well as the amount of biases and contamination produced by four DNA extraction protocols. We also addressed how bacterial community characteristics would be affected by the number of individuals or individual body size used for DNA extraction. Most extraction methods yielded similar results in terms of bacterial diversity and composition for A. cephalotes (~15 mm). In contrast, greater amounts of artefactual sequences and contaminations, as well as noticeable differences in bacterial community characteristics were observed between extraction methods for P. penetrator (~5 mm). We also found that large (~15 mm) and small (~5 mm) A. cephalotes individuals harbour different bacterial communities. Our benchmark suggests that cuticular microbiota of single individual insects can be reliably retrieved provided that blank controls, appropriate data cleaning, and individual body size and functional role within insect society are considered in the experiment. | ||||
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| ISSN | 1755-0998 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 781 | ||
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| Author | Van Langenhove, Leandro ; Depaepe, Thomas ; Verryckt, Lore T. ; Fuchslueger, Lucia ; Donald, Julian ; Celine, Leroy ; Krishna Moorthy, Sruthi M. ; Gargallo-Garriga, Albert ; Farnon Ellwood, M. D.; Verbeeck, Hans ; Van Der Straeten, Dominique ; Penuelas, Josep ; Janssens, Ivan A. | ||||
| Title |
Comparable canapy and soil free living nitrogen fixation rates in e lowland tropical forest | Type | Journal Article | ||
| Year | 2021 | Publication | Science of the total environment | Abbreviated Journal | |
| Volume | 754 | Issue | Pages | ||
| Keywords | Biodiversité ; Systématique ; phylogénie ; taxonomie ; Ecologie, Environnement ; Ecosystèmes ; Biologie végétale ; Botanique ; Biodiversité | ||||
| Abstract | Biological nitrogen fixation (BNF) is a fundamental part of nitrogen cycling in tropical forests, yet little is known about the contribution made by free-living nitrogen fixers inhabiting the often-extensive forest canopy. We used the acetylene reduction assay, calibrated with 15N2, to measure free-living BNF on forest canopy leaves, vascular epiphytes, bryophytes and canopy soil, as well as on the forest floor in leaf litter and soil. We used a combination of calculated and published component densities to upscale free-living BNF rates to the forest level. We found that bryophytes and leaves situated in the canopy in particular displayed high mass-based rates of free-living BNF. Additionally, we calculated that nearly 2 kg of nitrogen enters the forest ecosystem through free-living BNF every year, 40% of which was fixed by the various canopy components. Our results reveal that in the studied tropical lowland forest a large part of the nitrogen input through free-living BNF stems from the canopy, but also that the total nitrogen inputs by free-living BNF are lower than previously thought and comparable to the inputs of reactive nitrogen by atmospheric deposition. | ||||
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| Publisher | Elsevier | Place of Publication | Editor | ||
| Language | Anglais | Summary Language | Original Title | ||
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| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 1006 | ||
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| Author | Aili, S.R.; Touchard, A.; Petitclerc, F.; Dejean, A.; Orivel, J.; Padula, M.P.; Escoubas, P.; Nicholson, G.M. | ||||
| Title |
Combined Peptidomic and Proteomic Analysis of Electrically Stimulated and Manually Dissected Venom from the South American Bullet Ant Paraponera clavata | Type | Journal Article | ||
| Year | 2017 | Publication | Journal of Proteome Research | Abbreviated Journal | J. Proteome Res. |
| Volume | 16 | Issue | 3 | Pages | 1339-1351 |
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| Abstract | Ants have evolved venoms rich in peptides and proteins used for predation, defense, and communication. However, they remain extremely understudied due to the minimal amount of venom secreted by each ant. The present study investigated the differences in the proteome and peptidome of the venom from the bullet ant, Paraponera clavata. Venom samples were collected from a single colony either by manual venom gland dissection or by electrical stimulation and were compared using proteomic methods. Venom proteins were separated by 2D-PAGE and identified by nanoLC-ESI-QTOF MS/MS. Venom peptides were initially separated using C18 reversed-phase high-performance liquid chromatography, then analyzed by MALDI-TOF MS. The proteomic analysis revealed numerous proteins that could be assigned a biological function (total 94), mainly as toxins, or roles in cell regulation and transport. This investigation found that ca. 73% of the proteins were common to venoms collected by the two methods. The peptidomic analysis revealed a large number of peptides (total 309) but with <20% shared by the two collection methods. There was also a marked difference between venoms obtained by venom gland dissection from different ant colonies. These findings demonstrate the rich composition and variability of P. clavata venom. | ||||
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| Publisher | American Chemical Society | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1535-3893 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 746 | ||
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| Author | Amusant, N.; Fournier, M.; Beauchene, J. | ||||
| Title |
Colour and decay resistance and its relationships in Eperua grandiflora | Type | Journal Article | ||
| Year | 2008 | Publication | Annals of Forest Science | Abbreviated Journal | Ann. For. Sci. |
| Volume | 65 | Issue | 8 | Pages | 806 |
| Keywords | natural durability; colour; decay resistance; variability; heartwood; tropical wood | ||||
| Abstract | Eperua grandiflora, which is widely distributed in the French Guiana forest region, shows high variability in decay resistance. Further information concerning this wood quality parameter is necessary, but standard testing methods are complex and time-consuming. We assessed the use of colorimetry to determine durability in heartwood samples from a range of trees. Eperua grandiflora colour parameters were measured using a CIELAB system, revealing that the tree effect was greater than the radial position and height effects. The wood samples were exposed to Coriolus versicolor and Antrodia sp. according to two European standards (En 350-1 and XP CEN TS 15083-1). Eperua grandiflora is more susceptible to brown rot. These two standards did not give the same durability classes. The high variation in natural durability was due to the tree effect. These two properties were found to be correlated and the assessment also distinguished the extreme durability classes but they are not sufficient to classify the class of durability of this species. | ||||
| Address | [Amusant, Nadine] CIRAD, PERSYT, UR Valorisat Bois Tropicaux, F-34538 Montpellier 5, France, Email: nadine.amusant@cirad.fr | ||||
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| Publisher | EDP SCIENCES S A | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1286-4560 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000261431600006 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 127 | ||
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| Author | Charles-Dominique, P.; Chave, J.; Dubois, M.A.; De Granville, J.J.; Riera, B.; Vezzoli, C. | ||||
| Title |
Colonization front of the understorey palm Astrocaryum sciophilum in a pristine rain forest of French Guiana | Type | Journal Article | ||
| Year | 2003 | Publication | Global Ecology and Biogeography | Abbreviated Journal | Glob. Ecol. Biogeogr. |
| Volume | 12 | Issue | 3 | Pages | 237-248 |
| Keywords | Astrocaryum sciophilum; French Guiana; neotropical palaeoecology; palm ecology; population edge; refuges; scatter-hoarding; seed dispersal; spatial pattern | ||||
| Abstract | Aims Astrocaryum sciophilum (Miq.) Pulle (Arecaceae) is an understorey palm, endemic to north-eastern South America with a patchy distribution. We tested the hypothesis that the spatial distribution of this palm species is not in equilibrium but is slowly colonizing the forest understorey. Location Inventories and seed dispersal studies were conducted in the undisturbed tropical forest close to the Nouragues research station, French Guiana. Additional data were collected in the entire territory of French Guiana. Methods We studied the demography of A. sciophilum on a 20-ha plot located at the edge of its distribution. The age of the palms was estimated by postulating an exponentially decreasing abundance by age class. Direct seed dispersal experiments were also conducted, to estimate dispersal parameters. The seeds of A. sciophilum were dispersed only by rodents. This information was used to parameterize a forest growth simulator, to study the spatial spread of this species. Results Within the sampling plot, the density of A. sciophilum dropped sharply from about 500 individuals per hectare to zero. The maturation age was estimated to be 170+/-70 years, and over 55 years with 95% confidence. Seed-dispersal experiments yielded an average seed dispersal distance of 11 m and a maximum estimated dispersal distance of 125 m across a generational span of 55 years to maturity. Therefore, the maximal estimated colonization speed is 2.3 m/y. Conclusions Empirical results and numerical simulations suggest that the boundary of the A. sciophilum population is a colonization front, and that the range of this species is slowly expanding. The implications of this result in respect of palaeoenvironmental changes in this region are discussed. | ||||
| Address | Natl Museum Nat Hist, Lab Ecol Gen, F-91800 Brunoy, France | ||||
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| Publisher | BLACKWELL PUBLISHING LTD | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0960-7447 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000182184100006 | Approved | no | ||
| Call Number | EcoFoG @ eric.marcon @ | Serial | 273 | ||
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| Author | Siebicke, L.; Steinfeld, G.; Foken, T. | ||||
| Title |
CO2-gradient measurements using a parallel multi-analyzer setup | Type | Journal Article | ||
| Year | 2011 | Publication | Atmospheric Measurement Techniques | Abbreviated Journal | Atmos. Meas. Tech. |
| Volume | 4 | Issue | 3 | Pages | 409-423 |
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| Abstract | Accurate CO2 concentration gradient measurements are needed for the computation of advective flux terms, which are part of the full Net Ecosystem Exchange (NEE) budget equation. A typical draw back of current gradient measurement designs in advection research is the inadequate sampling of complex flow phenomena using too few observation points in space and time. To overcome this draw back, a new measurement design is presented which allows the parallel measurement of several sampling points at a high frequency. Due to the multi-analyzer nature of the design, inter-instrument bias becomes more of a concern compared to conventional setups. Therefore a statistical approach is presented which allows for accurate observations of concentration gradients, which are typically small in relation to analyzer accuracy, to be obtained. This bias correction approach applies a conditional, time dependent signal correction. The correction depends on a mixing index based on cross correlation analysis, which characterizes the degree of mixing of the atmosphere between individual sample points. The approach assumes statistical properties of probability density functions (pdf) of concentration differences between a sample point and the field average which are common to the pdf's from several sample points. The applicability of the assumptions made was tested by Large Eddy Simulation (LES) using the model PALM and could be verified for a test case of well mixed conditions. The study presents concentration time series before and after correction, measured at a 2 m height in the sub-canopy at the FLUXNET spruce forest site Waldstein-Weidenbrunnen (DE-Bay), analyzes the dependence of statistical parameters of pdf's from atmospheric parameters such as stratification, quantifies the errors and evaluates the performance of the bias correction approach. The improvements that are achieved by applying the bias correction approach are one order of magnitude larger than possible errors associated with it, which is a strong incentive to use the correction approach. In conclusion, the presented bias correction approach is well suited for – but not limited to – horizontal gradient measurements in a multi-analyzer setup, which would not have been reliable without this approach. Finally, possible future improvements of the bias correction approach are outlined and further fields of application indicated. | ||||
| Address | [Siebicke, L.; Foken, T.] Univ Bayreuth, Dept Micrometeorol, Bayreuth, Germany, Email: lukas.siebicke@ecofog.gf | ||||
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| Publisher | Copernicus Gesellschaft Mbh | Place of Publication | Editor | ||
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| Series Volume | Series Issue | Edition | |||
| ISSN | 1867-1381 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | ISI:000288911000002 | Approved | no | ||
| Call Number | EcoFoG @ webmaster @ | Serial | 303 | ||
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