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| Author | Orivel, J.; Malé, P.-J.; Lauth, J.; Roux, O.; Petitclerc, F.; Dejean, A.; Leroy, C. | ||||
| Title | Trade-offs in an ant–plant–fungus mutualism | Type | Journal Article | ||
| Year | 2017 | Publication | Proceedings of the Royal Society B: Biological Sciences | Abbreviated Journal | Proc Biol Sci |
| Volume | 284 | Issue | 1850 | Pages | 20161679 |
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| Abstract | Species engaged in multiple, simultaneous mutualisms are subject to trade-offs in their mutualistic investment if the traits involved in each interaction are overlapping, which can lead to conflicts and affect the longevity of these associations. We investigate this issue via a tripartite mutualism involving an ant plant, two competing ant species and a fungus the ants cultivate to build galleries under the stems of their host plant to capture insect prey. The use of the galleries represents an innovative prey capture strategy compared with the more typical strategy of foraging on leaves. However, because of a limited worker force in their colonies, the prey capture behaviour of the ants results in a trade-off between plant protection (i.e. the ants patrol the foliage and attack intruders including herbivores) and ambushing prey in the galleries, which has a cascading effect on the fitness of all of the partners. The quantification of partners' traits and effects showed that the two ant species differed in their mutualistic investment. Less investment in the galleries (i.e. in fungal cultivation) translated into more benefits for the plant in terms of less herbivory and higher growth rates and vice versa. However, the greater vegetative growth of the plants did not produce a positive fitness effect for the better mutualistic ant species in terms of colony size and production of sexuals nor was the mutualist compensated by the wider dispersal of its queens. As a consequence, although the better ant mutualist is the one that provides more benefits to its host plant, its lower host–plant exploitation does not give this ant species a competitive advantage. The local coexistence of the ant species is thus fleeting and should eventually lead to the exclusion of the less competitive species. | ||||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 745 | ||
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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 | ||
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| ISSN | 1535-3893 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 746 | ||
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| Author | Chang, S.-S.; Quignard, F.; Clair, B. | ||||
| Title | The effect of sectioning and ultrasonication on the mesoporosity of poplar tension wood | Type | Journal Article | ||
| Year | 2017 | Publication | Wood Science and Technology | Abbreviated Journal | |
| Volume | 51 | Issue | 3 | Pages | 507-516 |
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| Abstract | Increasing interest in understanding tension stress generation in tension wood with fibres having a gelatinous layer (G-layer) has focused attention on the specific role of this layer. To distinguish its contribution from those of other wall layers, the G-layer of wood sections was isolated by ultrasonication. The aim of this study was to assess the effect of sectioning and of the ultrasonic treatment on the mesoporosity of tension wood using nitrogen adsorption–desorption analysis. The results showed that the process of isolating the G-layer using ultrasonication strongly affects its mesoporosity. Most damage was found to occur during sectioning rather than as a result of the 15-min ultrasonic treatment. | ||||
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| ISSN | 1432-5225 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ Chang2017 | Serial | 782 | ||
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| Author | Stahl, C.; Fontaine, S.; Klumpp, K.; Picon-Cochard, C.; Grise, M.M.; Dezecache, C.; Ponchant, L.; Freycon, V.; Blanc, L.; Bonal, D.; Burban, B.; Soussana, J.-F.; Blanfort, V. | ||||
| Title | Continuous soil carbon storage of old permanent pastures in Amazonia | Type | Journal Article | ||
| Year | 2017 | Publication | Global Change Biology | Abbreviated Journal | Glob Change Biol |
| Volume | 23 | Issue | 8 | Pages | 3382-3392 |
| Keywords | carbon storage; CN coupling; deep soil; mixed-grass pasture; native forest | ||||
| Abstract | Amazonian forests continuously accumulate carbon (C) in biomass and in soil, representing a carbon sink of 0.42–0.65 GtC yr−1. In recent decades, more than 15% of Amazonian forests have been converted into pastures, resulting in net C emissions (~200 tC ha−1) due to biomass burning and litter mineralization in the first years after deforestation. However, little is known about the capacity of tropical pastures to restore a C sink. Our study shows in French Amazonia that the C storage observed in native forest can be partly restored in old (≥24 year) tropical pastures managed with a low stocking rate (±1 LSU ha−1) and without the use of fire since their establishment. A unique combination of a large chronosequence study and eddy covariance measurements showed that pastures stored between −1.27 ± 0.37 and −5.31 ± 2.08 tC ha−1 yr−1 while the nearby native forest stored −3.31 ± 0.44 tC ha−1 yr−1. This carbon is mainly sequestered in the humus of deep soil layers (20–100 cm), whereas no C storage was observed in the 0- to 20-cm layer. C storage in C4 tropical pasture is associated with the installation and development of C3 species, which increase either the input of N to the ecosystem or the C:N ratio of soil organic matter. Efforts to curb deforestation remain an obvious priority to preserve forest C stocks and biodiversity. However, our results show that if sustainable management is applied in tropical pastures coming from deforestation (avoiding fires and overgrazing, using a grazing rotation plan and a mixture of C3 and C4 species), they can ensure a continuous C storage, thereby adding to the current C sink of Amazonian forests. | ||||
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| ISSN | 1365-2486 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 783 | ||
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| Author | Dejean, A.; Rodríguez-Pérez, H.; Carpenter, J.M.; Azémar, F.; Corbara, B. | ||||
| Title | The predatory behavior of the Neotropical social wasp Polybia rejecta | Type | Journal Article | ||
| Year | 2017 | Publication | Behavioural Processes | Abbreviated Journal | |
| Volume | 140 | Issue | Pages | 161-168 | |
| Keywords | Epiponine wasps; Polistinae; Predation; Prey selection; Recruitment; Vespidae | ||||
| Abstract | Abstract We experimentally studied the predatory behavior of Polybia rejecta (Vespidae, Polistinae, Epiponini) towards 2–88 mm-long insects attracted to a UV light trap. Foragers, which began to hunt at 6:30, selected 4–14 mm-long prey insects. Prey detection by sight by hovering wasps was confirmed using decoys. After the wasps landed and walked along a sinuous path, prey were detected by contact or from a distance (1–3 cm). This was followed by seizure, stinging (contrarily to most other known cases), prey manipulation and retrieval. Prey that flew off might be caught in flight. The prey load, representing 30.7% of a forager’s weight, was optimized by capturing up to six small prey or two medium-sized prey successively (both of which might be consumed in situ). The foragers cut off the wings of larger prey or cut them into two pieces and returned to gather the second piece. The handling time increased exponentially with the weight of the prey. Partial loading (i.e., retrieving a load much inferior to the maximum possible) was likely related to social facilitation, a form of nest-based recruitment that was demonstrated through the experimental elimination of local enhancement by removing foragers (both mechanisms favor the exploitation of favorable patches). | ||||
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| ISSN | 0376-6357 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 751 | ||
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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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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 753 | ||
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| Author | Fukami, T.; Nakajima, M.; Fortunel, C.; Fine, P.V.A.; Baraloto, C.; Russo, S.E.; Peay, K.G. | ||||
| Title | Geographical variation in community divergence: insights from tropical forest monodominance by ectomycorrhizal trees | Type | Journal Article | ||
| Year | 2017 | Publication | American Naturalist | Abbreviated Journal | American Naturalist |
| Volume | 190 | Issue | Pages | S105-S122 | |
| Keywords | Community assembly; Mycorrhizae; Plant traits; Plant-soil feedback; Priority effects; Species pools | ||||
| Abstract | Convergence occurs in both species traits and community structure, but how convergence at the two scales influences each other remains unclear. To address this question, we focus on tropical forest monodominance, in which a single, often ectomycorrhizal (EM) tree species occasionally dominates forest stands within a landscape otherwise characterized by diverse communities of arbuscular mycorrhizal (AM) trees. Such monodominance is a striking potential example of community divergence resulting in alternative stable states. However, it is observed only in some tropical regions. A diverse suite of AM and EM trees locally codominate forest stands elsewhere. We develop a hypothesis to explain this geographical difference using a simulation model of plant community assembly. Simulation results suggest that in a region with a few EM species (e.g., South America), EM trees experience strong selection for convergent traits that match the abiotic conditions of the environment. Consequently, EM species successfully compete against other species to form monodominant stands via positive plant-soil feedbacks. By contrast, in a region with many EM species (e.g., Southeast Asia), species maintain divergent traits because of complex plant-soil feedbacks, with no species having traits that enablemonodominance. An analysis of plant trait data from Borneo and Peruvian Amazon was inconclusive. Overall, this work highlights the utility of geographical comparison in understanding the relationship between trait convergence and community convergence. © 2017 by The University of Chicago. | ||||
| Address | School of Biological Sciences, University of Nebraska, Lincoln, NE, United States | ||||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 761 | ||
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| Author | Denis, T.; Richard-Hansen, C.; Brunaux, O.; Etienne, M.-P.; Guitet, S.; Herault, B. | ||||
| Title | Biological traits, rather than environment, shape detection curves of large vertebrates in neotropical rainforests | Type | Journal Article | ||
| Year | 2017 | Publication | Ecological Applications | Abbreviated Journal | Ecol Appl |
| Volume | 27 | Issue | 5 | Pages | 1564-1577 |
| Keywords | abundance; camouflage; distance sampling; encounter rate; French Guiana; hunting vulnerability; line transect; Neotropical terra firme rainforests; relative abundance | ||||
| Abstract | Line transect surveys are widely used in Neotropical rainforests to estimate the population abundance of medium- and large-sized vertebrates. The use of indices such as encounter rate has been criticized because the probability of animal detection may fluctuate due to the heterogeneity of environmental conditions among sites. In addition, the morphological and behavioral characteristics (biological traits) of species affect their detectability. In this study, we compared the extent to which environmental conditions and species’ biological traits bias abundance estimates in terra firme rainforests in French Guiana. The selected environmental conditions included both physical conditions and forest structure covariates, while the selected biological traits included the morphological and behavioral characteristics of species. We used the distance sampling method to model the detection probability as an explicit function of environmental conditions and biological traits and implemented a model selection process to determine the relative importance of each group of covariates. Biological traits contributed to the variability of animal detectability more than environmental conditions, which had only a marginal effect. Detectability was best for large animals with uniform or disruptive markings that live in groups in the canopy top. Detectability was worst for small, solitary, terrestrial animals with mottled markings. In the terra firme rainforests that represent ~80% of the Amazonia and Guianas regions, our findings support the use of relative indices such as the encounter rate to compare population abundance between sites in species-specific studies. Even though terra firme rainforests may appear similar between regions of Amazonia and the Guianas, comparability must be ensured, especially in forests disturbed by human activity. The detection probability can be used as an indicator of species’ vulnerability to hunting and, thus, to the risk of local extinction. Only a few biological trait covariates are required to correctly estimate the detectability of the majority of medium- and large-sized vertebrates. Thus, a biological trait model could be useful in predicting the detection probabilities of rare, uncommon, or localized species for which few data are available to fit the detection function. | ||||
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| ISSN | 1939-5582 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 764 | ||
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| Author | Gruhn, G.; Dumez, S.; Moreau, P.-A.; Roy, M.; Morreale, O.; Schimann, H.; Courtecuisse, R.. | ||||
| Title | The genus Resinicium in French Guiana and the West Indies: a morphological and molecular survey, revealing Resinicium grandisporum sp. nov. | Type | Journal Article | ||
| Year | 2017 | Publication | Cryptogamie, Mycologie | Abbreviated Journal | |
| Volume | 38 | Issue | 4 | Pages | 1-15 |
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| Abstract | A revision of Resinicium collections (Basidiomycota, Hymenochaetales) from French Guiana and French West Indies is provided, and a new species, Resinicium grandisporum sp. nov., supported by morphological as well as phylogenetic analyses based on ITS DNA sequences, is described and illustrated. An updated key of the genus Resinicium is also provided, which includes species previously described from outside of the studied area. | ||||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 779 | ||
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| Author | Duplais, C.; Estevez, Y. | ||||
| Title | Tandem Biocatalysis Unlocks the Challenging de Novo Production of Plant Natural Products | Type | Journal Article | ||
| Year | 2017 | Publication | ChemBioChem | Abbreviated Journal | ChemBioChem |
| Volume | 18 | Issue | 22 | Pages | 2192-2195 |
| Keywords | alkaloids; biosynthesis; enzyme catalysis; protein engineering; terpenes | ||||
| Abstract | Intimate partnership: Knowledge of the biocatalytic cascades in different cellular compartments is limited, but deciphering these systems in nature can be used to inspire synthetic strategies. Two studies report new insights into the biosynthesis of alkaloids and sesterterpenoids in plants. This highlight presents these novel biotransformations to illustrate how tandem biocatalysis can impact the future of natural product production. | ||||
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| ISSN | 1439-7633 | ISBN | Medium | ||
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Approved | no | |||
| Call Number | EcoFoG @ webmaster @ | Serial | 780 | ||
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