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Author (down) Le Guen, V.; Rodier-Goud, M.; Troispoux, V.; Xiong, T.C.; Brottier, P.; Billot, C.; Seguin, M. openurl 
  Title Characterization of polymorphic microsatellite markers for Microcyclus ulei, causal, agent of South American leaf blight of rubber trees Type Journal Article
  Year 2004 Publication Molecular Ecology Notes Abbreviated Journal Mol. Ecol. Notes  
  Volume 4 Issue 1 Pages 122-124  
  Keywords Hevea brasiliensis; Microcyclus ulei; microsatellite markers; phytopathogenic fungi; South American leaf blight  
  Abstract South American leaf blight caused by the ascomycete Microcyclus Wei is the most harmful disease of the rubber tree in Latin America and a potential threat to Asiatic and African natural rubber production. Until now, the variability of this fungus was assessed through observation of pathogenicity of isolates on a range of rubber tree clones with known resistance reactions. The present study describes the process used to design 11 microsatellite markers and evaluates their usefulness in detecting genetic polymorphism. Nine of these markers were polymorphic among six isolates from Brazil (with two to three alleles per locus) and five markers were polymorphic among four isolates from French Guiana (with two to four alleles per locus).  
  Address CIRAD, F-97387 Kourou, France, Email: vincent.le_guen@cirad.fr  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1471-8278 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000189159500037 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 265  
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Author (down) Le Guen, R.; Corbara, B.; Rossi, V.; Azémar, F.; Dejean, A. url  openurl
  Title Reciprocal protection from natural enemies in an ant-wasp association Type Journal Article
  Year 2015 Publication Comptes Rendus – Biologies Abbreviated Journal Comptes Rendus – Biologies  
  Volume 338 Issue 4 Pages 255-259  
  Keywords Aggressiveness; Arboreal ants; Azteca; Polybia; Protection mutualism; Social wasps  
  Abstract Abstract We show that in French Guiana the large carton nests of Azteca chartifex, a territorially-dominant arboreal dolichoderine ant, are protected from bird attacks when this ant lives in association with Polybia rejecta, an epiponine social wasp. Because A. chartifex colonies are well known for their ability to divert army ant raids from the base of their host tree so that they protect their associated wasps from these raids, there is a reciprocal benefit for these two partners, permitting us to call this association a mutualism. We also show that P. rejecta nests are significantly less often attacked by birds than are those of two compared epiponine social wasp species. Furthermore, experimentation using a standardized protocol demonstrated the significantly higher aggressiveness of P. rejecta compared to seven other wasp species. We conclude that the efficacious protection of its associated ant nests is likely due to the extreme aggressiveness of P. rejecta. © 2015 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.  
  Address CNRS, Écologie des forêts de Guyane (UMR-CNRS 8172), Campus agronomique, BP 316Kourou cedex, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 24 April 2015 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 600  
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Author (down) Laybros, A.; Aubry-Kientz, M.; Féret, J.-B.; Bedeau, C.; Brunaux, O.; Derroire, G.; Vincent, G. doi  openurl
  Title Quantitative airborne inventories in dense tropical forest using imaging spectroscopy Type Journal Article
  Year 2020 Publication Remote Sensing Abbreviated Journal Remote Sens.  
  Volume 12 Issue 10 Pages 1577  
  Keywords Hyperspectral; LiDAR; Species diversity; Tropical forest; Cost effectiveness; Discriminant analysis; Infrared devices; Infrared radiation; Logistic regression; Remote sensing; Tropics; Classification accuracy; Classification performance; Linear discriminant analysis; Operational applications; Regularized discriminant analysis; Remote sensing technology; Short wave infrared bands; Visible and near infrared; Forestry  
  Abstract Tropical forests have exceptional floristic diversity, but their characterization remains incomplete, in part due to the resource intensity of in-situ assessments. Remote sensing technologies can provide valuable, cost-effective, large-scale insights. This study investigates the combined use of airborne LiDAR and imaging spectroscopy to map tree species at landscape scale in French Guiana. Binary classifiers were developed for each of 20 species using linear discriminant analysis (LDA), regularized discriminant analysis (RDA) and logistic regression (LR). Complementing visible and near infrared (VNIR) spectral bands with short wave infrared (SWIR) bands improved the mean average classification accuracy of the target species from 56.1% to 79.6%. Increasing the number of non-focal species decreased the success rate of target species identification. Classification performance was not significantly affected by impurity rates (confusion between assigned classes) in the non-focal class (up to 5% of bias), provided that an adequate criterion was used for adjusting threshold probability assignment. A limited number of crowns (30 crowns) in each species class was sufficient to retrieve correct labels effectively. Overall canopy area of target species was strongly correlated to their basal area over 118 ha at 1.5 ha resolution, indicating that operational application of the method is a realistic prospect (R2 = 0.75 for six major commercial tree species). © 2020 by the authors.  
  Address Cirad, UMR EcoFoG (AgroParistech, CNRS, INRAE, Université des Antilles, Université de la Guyane), Kourou, French Guiana, 97379, France  
  Corporate Author Thesis  
  Publisher Mdpi Ag Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 20724292 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 969  
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Author (down) Lauth, J.; Ruiz-González, M.X.; Orivel, J. pdf  url
openurl 
  Title New findings in insect fungiculture: Have ants developed non-food, agricultural products? Type Journal Article
  Year 2011 Publication Communicative & Integrative Biology Abbreviated Journal Comm & Integr Biol  
  Volume 4 Issue 1942-0889 Pages 728-730  
  Keywords  
  Abstract The interaction between Allomerus plant-ants and an ascomycete fungus growing on and strengthening their galleries is not opportunistic. We previously demonstrated that this association is highly specific as only one fungal species represented by a few haplotypes was found associated with the ants. We also discovered that the ants' behavior revealed a major investment in manipulating and enhancing the growth of their associated fungus. We have growing evidence that this specificity is consistent with selection by the ants. Here, we discuss this selection within the framework of insect agriculture, as we believe these ants fulfill all of the prerequisites to be considered as farmers. Allomerus ants promote their symbiont's growth, protect it from potential pathogens and select specific cultivars. Taken together, we think that the interaction between Allomerus ants and their cultivar might represent the first case of insect fungiculture used as a means of obtaining building material.  
  Address  
  Corporate Author Thesis  
  Publisher Landes Bioscience Inc. Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 379  
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Author (down) Laurans, M.; Martin, O.; Nicolini, E.; Vincent, G. url  openurl
  Title Functional traits and their plasticity predict tropical trees regeneration niche even among species with intermediate light requirements Type Journal Article
  Year 2012 Publication Journal of Ecology Abbreviated Journal J. Ecol.  
  Volume 100 Issue 6 Pages 1440-1452  
  Keywords Canopy disturbance; Determinants of plant community diversity and structure; Growth rate; Irradiance; Leaf life span; Leaf mass per area; Niche differentiation; Phenotypic plasticity; Shade tolerance; Tropical moist forest  
  Abstract Niche differentiation is a key issue in the current debate on community assembly mechanisms. In highly diverse moist tropical forests, tree species sensitivity to canopy openness is thought to be a major axis in niche differentiation. In the past, the syndrome of traits driving the demographic trade-off involved in the niche-based theory of coexistence has always been established among species situated at the two extremities of the shade-tolerance gradient, even though most tropical tree species have intermediate light requirements. In addition, trait plasticity has seldom been linked to tropical tree species distribution along environmental gradients. This article examines covariations between leaf traits, whole-plant traits and niche parameters among 14 tree species with intermediate light requirements in French Guiana and across a range of canopy openness. Each functional trait measured under field conditions was characterized by a median value and a degree of plasticity expressed under contrasting light regimes. Niche differentiation was characterized in terms of spatial light gradient. We first examined covariations between functional traits then explored to what degree the median value and plasticity in functional traits could predict light niche characteristics at the sapling stage and the ontogenetic change in light availability estimated by adult stature. Leaf mass per area (LMA) was positively correlated with leaf life span (LLS); species with higher LMA and higher LLS displayed lower diameter growth rates (GRs) and lower responsiveness to canopy gap at both whole-plant and population levels. This proved that the relationships previously established over a broader range of species held true within the narrow range of the light requirements covered. Height GR plasticity accounted for 49% of the variation in light niche optimum. LMA plasticity, unlike LLS plasticity, was significantly correlated with light niche breadth and adult stature. Synthesis. This study demonstrates the relevance of considering the phenotypic plasticity in functional traits in community ecology, particularly for quantifying breadth of species distribution over environmental gradients. Our findings did not support Hubbell's hypothesis of functional equivalence and suggest that even a rather subtle variation in forest canopy disturbance promotes the coexistence of tropical tree species. © 2012 The Authors. Journal of Ecology © 2012 British Ecological Society.  
  Address UMR AMAP, IRD, TA A-51/PS2, Bd de la Lironde, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 00220477 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 7 November 2012; Source: Scopus; Coden: Jecoa; doi: 10.1111/j.1365-2745.2012.02007.x; Language of Original Document: English; Correspondence Address: Laurans, M.; UMR, AMAP, CIRAD TA A-51/PS1, Bd de la Lironde, 34398 Montpellier Cedex 5, France; email: laurans@cirad.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 445  
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Author (down) Laurans, M.; Herault, B.; Vieilledent, G.; Vincent, G. url  openurl
  Title Vertical stratification reduces competition for light in dense tropical forests Type Journal Article
  Year 2014 Publication Forest Ecology and Management Abbreviated Journal For. Ecol. Manage.  
  Volume 329 Issue Pages 79-88  
  Keywords Adult stature; French Guiana; Hierarchical bayesian model; Local crowding; Niche partitioning; Bayesian networks; Growth rate; Adult stature; French Guiana; Hierarchical Bayesian modeling; Local crowding; Niche partitioning; Reforestation  
  Abstract Differential growth response to light level is widely accepted as a potential mechanism for maintaining tree species richness in tropical forests. The position of tree species in the hierarchy of the canopy is considered an important indicator of species light capture and growth strategy. Paradoxically, the relative importance of species identity and competition for light in determining individual tree growth is poorly documented at the adult stage. In this study, we used a hierarchical Bayesian model to quantify the overall importance of species identity, light and belowground competition as determinants of tree growth in French Guiana tropical forest. Light competitive status is assessed by a crown exposure score and below ground competition is estimated from local crowding. We examined species sensitivity to both types of competition in relation to adult stature. Our results are based on annual diameter increments of more than 13,510 stems from 282 species monitored over 10years. Mean annual growth rate was 0.11cmy-1 with species identity explaining 35% of the individual variation in growth rate. Crown exposure and local crowding explained 3.5% and 2.4% of the variation in growth rate, respectively. Predicted changes in growth rate as crown exposure (resp. local crowding) index changed from lower to upper interquartile level was 0.03cmy-1 (resp. 0.02cmy-1). Species sensitivity to crown exposure and to local crowding were positively correlated (i) with predicted growth rate at high-light standardized conditions and (ii) with adult stature.This vertical niche partitioning is invoked to explain the limited contribution made by level of light competition for predicting individual tropical tree growth as the community-level response is dominated by the abundance of small-statured species with low sensitivity to light level.Light appears to drive the stem growth rate of tropical trees through species differentiation more than through individual tree growth limitation. This vertical stratification complements the previously reported regeneration niche and together these provide evidence for light niche partitioning in the three-dimensional space of tropical forests. © 2014 Elsevier B.V.  
  Address IRD, UMR AMAP, TA A-51/PS1, Bd de la Lironde, 34398 Montpellier Cedex 5, France  
  Corporate Author Thesis  
  Publisher Elsevier Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 03781127 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Export Date: 30 July 2014; Coden: Fecmd; Correspondence Address: Laurans, M.; CIRAD, UMR AMAP, TA A-51/PS1, Bd de la Lironde, 34398 Montpellier Cedex 5, France; email: laurans@cirad.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 551  
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Author (down) Latouche-Halle, C.; Ramboer, A.; Bandou, E.; Caron, H.; Kremer, A. openurl 
  Title Long-distance pollen flow and tolerance to selfing in a neotropical tree species Type Journal Article
  Year 2004 Publication Molecular Ecology Abbreviated Journal Mol. Ecol.  
  Volume 13 Issue 5 Pages 1055-1064  
  Keywords Dicorynia guianensis; microsatellites; outcrossing rate; pollen flow; reproductive success; tropical tree  
  Abstract Outcrossing rates, pollen dispersal and male mating success were assessed in Dicorynia guianensis Amshoff, a neotropical tree endemic to the Guiana shield. All adult trees within a continuous area of 40 ha (n = 157) were mapped, and were genotyped with six microsatellite loci. In addition, progenies were genotyped from 22 mature trees. At the population level, the species was mostly outcrossing (t(m) = 0.89) but there was marked variation among individuals. One tree exhibited mixed mating, confirming earlier results obtained with isozymes that D. guianensis can tolerate selfing. A Bayesian extension of the fractional paternity method was used for paternity analysis, and was compared with the neighbourhood method used widely for forest trees. Both methods indicated that pollen dispersal was only weakly related to distance between trees within the study area, and that the majority (62%) of pollen came from outside the study stand. Using maximum likelihood, male potential population size was estimated to be 1119, corresponding to a neighbourhood size of 560 hectares. Male mating success was, however, related to the diameter of the stem and to flowering intensity assessed visually. The mating behaviour of D. guianensis is a combination of long-distance pollen flow and occasional selfing. The species can still reproduce when it is extremely rare, either by selfing or by dispersing pollen at long distances. These results, together with the observation that male mating success was correlated with the size of the trees, could be implemented in management procedures aiming at regenerating the species.  
  Address INRA, UMR Ecol Forets Guyane, F-97387 Kourou, France, Email: caron@pierroton.mra.fr  
  Corporate Author Thesis  
  Publisher BLACKWELL PUBLISHING LTD Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-1083 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000221016300007 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 237  
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Author (down) Latouche-Hallé, C.; Ramboer, A.; Bandou, E.; Caron, H.; Kremer, A. url  openurl
  Title Nuclear and chloroplast genetic structure indicate fine-scale spatial dynamics in a neotropical tree population Type Journal Article
  Year 2003 Publication Heredity Abbreviated Journal Heredity  
  Volume 91 Issue 2 Pages 181-190  
  Keywords Dicorynia guianensis; Gene flow; Genetic differentiation; Microsatellites; Spatial analysis; Tropical tree; gene flow; genetic structure; population genetics; spatial analysis; tree; tropical forest; Cell Nucleus; Chloroplasts; Cohort Studies; DNA, Plant; French Guiana; Genetic Markers; Pollen; Population Dynamics; Seeds; Trees; Variation (Genetics); French Guiana; Dicorynia guianensis; Embryophyta  
  Abstract Dicorynia guianensis is a canopy tree, endemic to the tropical rain forest of French Guiana. We compared generational and spatial genetic structure for maternally and biparentally inherited markers in two cohorts (adult and seedling) in order to infer processes shaping the distribution of genetic diversity. The study was conducted on a 40 ha study plot located at Paracou near Kourou, where 172 adults trees and 375 saplings were sampled. Aggregation of trees was therefore suggested at different distances, ranging from 100 to 400 m. There was a strong link between demographic and genetic spatial structures at small distances (less than 100 m) that is likely to be the consequence of restricted seed dispersal. Genetic differentiation was more pronounced between spatial aggregates than between cohorts. Despite the spatial differentiation, the species was able to maintain high levels of diversity for maternal genomes, suggesting rapid turnover of aggregates. Spatial autocorrelation was larger for chloroplast than nuclear markers indicating a strong asymmetry between pollen and seed flow. Fixation indices indicated a lower heterozygote deficiency for the adults, maybe because of gradual elimination of selfed trees. Genetic relatedness at lower distances was higher in adult trees than in saplings, as a result of generation overlapping in the adult cohort. Overall, our results confirm earlier biological knowledge about the dispersion mechanisms of the species, and lead to an enhanced role of spatial processes in the dynamics of genetic diversity of D. guianensis.  
  Address INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018067x (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Cited By (since 1996): 34; Export Date: 22 October 2011; Source: Scopus; Coden: Hdtya; doi: 10.1038/sj.hdy.6800296; PubMed ID: 12886285; Language of Original Document: English; Correspondence Address: Caron, H.; INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France; email: caron@pierroton.inra.fr; Chemicals/CAS: DNA, Plant; Genetic Markers Approved no  
  Call Number EcoFoG @ webmaster @ Serial 358  
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Author (down) LaPierre, L.; Hespenheide, H.; Dejean, A. openurl 
  Title Wasps robbing food from ants: a frequent behavior? Type Journal Article
  Year 2007 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften  
  Volume 94 Issue 12 Pages 997-1001  
  Keywords cleptobiosis; social wasps; charterginus; polybioides; plant-ants  
  Abstract Food robbing, or cleptobiosis, has been well documented throughout the animal kingdom. For insects, intrafamilial food robbing is known among ants, but social wasps (Vespidae; Polistinae) taking food from ants has, to the best of our knowledge, never been reported. In this paper, we present two cases involving social wasps robbing food from ants associated with myrmecophytes. (1) Polybioides tabida F. (Ropalidiini) rob pieces of prey from Tetraponera aethiops Smith (Formicidae; Pseudomyrmecinae) specifically associated with Barteria fistulosa Mast. (Passifloraceae). (2) Charterginus spp. (Epiponini) rob food bodies from myrmecophytic Cecropia (Cecropiaceae) exploited by their Azteca mutualists (Formicidae; Dolichoderinae) or by opportunistic ants (that also attack cleptobiotic wasps). We note here that wasps gather food bodies (1) when ants are not yet active; (2) when ants are active, but avoiding any contact with them by flying off when attacked; and (3) through the coordinated efforts of two to five wasps, wherein one of them prevents the ants from leaving their nest, while the other wasps freely gather the food bodies. We suggest that these interactions are more common than previously thought.  
  Address CNRS Guyane, UPS2561, UMR5174, F-97300 Cayenne, France, Email: llapierre@lowercolumbia.edu  
  Corporate Author Thesis  
  Publisher SPRINGER Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-1042 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000250980800006 Approved no  
  Call Number EcoFoG @ eric.marcon @ Serial 153  
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Author (down) Lang, G.; Marcon, E.; Puech, F. doi  openurl
  Title Distance-based measures of spatial concentration: introducing a relative density function Type Journal Article
  Year 2020 Publication Annals of Regional Science Abbreviated Journal Ann. Reg. Sci.  
  Volume 64 Issue 2 Pages 243-265  
  Keywords Agglomeration; Aggregation; Economic geography; Point patterns; Spatial concentration; accuracy assessment; econometrics; economic activity; economic geography; industrial agglomeration; industrial location; location decision; spatial analysis; spatial distribution  
  Abstract For more than a decade, distance-based methods have been widely employed and constantly improved in spatial economics. These methods are a very useful tool for accurately evaluating the spatial distribution of economic activity. We introduce a new distance-based statistical measure for evaluating the spatial concentration of industries. The m function is the first relative density function to be proposed in economics. This tool supplements the typology of distance-based methods recently drawn up by Marcon and Puech (J Econ Geogr 3(4):409–428, 2003). By considering several simulated and real examples, we show the advantages and the limits of the m function for detecting spatial structures in economics. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.  
  Address RITM, Univ. Paris-Sud, Université Paris-Saclay and CREST, Sceaux, France  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 05701864 (Issn) ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number EcoFoG @ webmaster @ Serial 976  
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