Éditeur(s) : HAL CCSD Wiley
Résumé :  
Pollination ecology and reproductive success of Jack-in-the-pulpit (Arisaema triphyllum) were studied in two natural populations in Québec, Canada. Individual A. triphyllum plants can be of three types: male, female or bisexual. In both populations studied, the presence of bisexual inflorescences was not negligible (13%), where 'female' and 'male' bisexual plants were categorised according to the relative number of stamens and ovaries. 'Male bisexual' plants produce only pollen and 'female bisexual' plants produce only fruit. Hence, A. triphyllum is a true dioecious plant, as each plant only reproduces through either the male or the female function. 'Female bisexual' plants were equivalent to female plants in terms of visitation rate by insects, fructification rate and production of berries and seeds. Neither agamospermy in female plants nor self-pollination in 'female bisexual' plants was found, thus A. triphyllum relies on insects for cross-pollination. Despite the long flowering cycle, a low visitation rate was documented: only 20-40% of inflorescences were visited, according to gender, by a mean of 1.5 insects. In this study, Mycetophilidae represented the most generically diversified and abundant family, as well as the most efficient insect pollinator, especially the genera Docosia and Mycetophila.
ISSN: 1435-8603

hal-01032127
https://hal.archives-ouvertes.fr/hal-01032127
DOI : 10.1111/j.1438-8677.2009.00192.x

Date de création : 1870-01-01

Éditeur(s) : London : Bell & Daldy
Siècle(s) traité(s) : 19
Droits : Domaine public
Provenance : Collectivité territoriale de Guyane. Bibliothèque Alexandre-Franconie
Permalien : http://www.manioc.org/patrimon/FRA11002
FRA11002

Résumé : Arbusto de 1 a 4 m de alto. Hojas alternas, aovadas, agudas a acuminadas en el ápice, aserradas. Bractéolas 5 a 7, lineales. Cáliz campanulado; corola blanca, roja purpúrea, amarilla o anaranjada, de tamaño variable, muy vistosa; tubo estaminal más largo que los pétalos. Cápsula oblonga de casi 3 cm de diámetro.
Arbuste de 1 à 4 m de haut. Feuilles alternes, ovées, pointues à acuminées à l’extrémité, denticulées. 5 à 7 petites bractées linéaires. Calice en forme de cloche; corolle blanche, rouge pourpre, jaune ou orangée, de taille variable, aux couleurs éclatantes; filet staminal plus long que les pétales. Capsule oblongue de presque 3 cm de diamètre.
Shrub, 1-4 m high.  Leaves 15cm x 10cm, spiraling around the stem,ovate, acute to acuminate at the tip, marginsserrate; flowers solitary, born on long stalks, in the axils of the upper leaves, epicalyx of 5-7 bractioles about 1 cm long, calyx cup-shaped 2.5cm long, corolla short-lived, showy, mainly red, but other varieties range frompurplish-red, yellow or orangeto white,variable in size,from 6-10cm,staminal tube longer than petals; capsules, rarely produced are oblong ca. 3 cm long, seeds globose ca.3 mm in diameter.
Originaria de Asia y cultivada en las zonas tropicales de todo el mundo.
Originaire d’Asie et cultivée dans les zones tropicales du monde entier.
Native to Asia and cultivated in tropical regions around the world.

http://www.tramil.net/fototeca/plant188

Résumé : Arbol de hasta 25 m de alto. Hojas simples elíptico-lanceoladas, de hasta 12 cm, acuminadas. Flores blancas, con líneas rojas, amarillas por dentro, pétalos de 1 cm. Cápsula muy estrecha y larga, de hasta 60 cm, a veces más y 3 mm de ancho; semillas plumoso-pubescentes.
Arbre pouvant atteindre 25 m de haut. Feuilles simples elliptico-lancéolées, pouvant atteindre 12 cm, acuminées. Fleurs blanches, avec des lignes rouges, jaunes à l';intérieur, pétales de 1 cm. Capsule fine et allongée, pouvant atteindre 60 cm, et parfois 3 mm et plus de largeur; graines plumeuses, velues.
Tree up to 25 m tall. Leaves simple, opposite in whorls, ovate-lanceolate 5-14 cm x 2-5.5 cm; inflorescence a panicle, flowers 2.5-3cm long x 3-3.4cm wide, white with pink lobes, yellow inside, with purple lines and yellow bands; fruit a capsule 35-77 cm x 4 mm; seeds feathery at both ends.
Originaria de Jamaica y La Hispañola. Introducida en las Antillas Menores y norte de Sudamérica.
Originaire de la Jamaïque et de l';île de Saint-Domingue. Introduite dans les Petites Antilles et le nord de l';Amérique du Sud.
Native

http://www.tramil.net/fototeca/plant113

Éditeur(s) : HAL CCSD Elsevier
Résumé :  
The within-population spatial structure of genetic diversity is shaped by demographic processes, including historical accidents such as forest perturbations. Information drawn from the analysis of the spatial distribution of genetic diversity is therefore inherently linked to demographic-historical processes that ultimately determine the fate of populations. All adult trees and saplings in a 1.4-ha plot within a mixed Norway spruce (Picea abies [L.] Karst) stand were characterised by means of chloroplast (paternally inherited) markers, and a large sub-sample of these were genotyped at mitochondrial (maternally inherited) molecular markers. These data were used to analyse the spatial distribution of genetic variation and to compare the patterns corresponding to the two marker types. The plot presented non-homogeneous local stem density in the younger cohorts, and the indirect effect of this source of variation on the spatial genetic structure was investigated. Results suggest that (i) spatially limited seed dispersal induced patchiness in genotype distribution, while pollen flow had a homogenising effect; (ii) deviations from random spatial structure were stronger in the demographically most stable portions of the stand, while they were weaker where sudden bursts of regeneration occurred; (iii) spatially overlapping adult and sapling cohorts displayed the same spatial genetic structure (stronger on stable areas, weaker in portions of the stand undergoing events of intense regeneration), which was substantiated by the influence of local demographic processes. Regeneration dynamics as modulated by demography thus influences the distribution of genetic diversity within the stand both in the younger life stages and in the adult population.
ISSN: 0378-1127

hal-01032063
https://hal.archives-ouvertes.fr/hal-01032063
DOI : 10.1016/j.foreco.2008.03.023

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Thermogravimetric results on the thermal degradation of isolated components extracted from shells of tropical fruit stones and seeds allowed us to establish the dependence of the yield of char obtained by high-temperature pyrolysis (600-900 °C) of lignocellulosic raw materials on the content of components in precursors...
ISSN: 1387-1811

hal-00809743
https://hal.univ-antilles.fr/hal-00809743
DOI : 10.1016/S1387-1811(03)00288-9

Éditeur(s) : HAL CCSD
Résumé : In the tropical rainforest of Amazonia, the factors driving the evolution of tree species remain poorly understood, and the relative influence of neutral and adaptive processes is continuously debated. In particular, local habitat patchiness draws much attention, as profound changes in the structure and composition of forest communities occur among micro-habitats. Thus, micro-environmental variations related to topography have frequently been invoked as drivers of adaptive radiation leading to sympatric speciation in Neotropical trees. On one hand, the hypothesis of local adaptation has never been investigated at the intra-specific level, i.e. within species currently undergoing population differentiation; on the other hand, many tree species are genetically structured over local scales due to neutral processes, mainly limited gene flow (caused by restricted pollen and seed dispersal). In this study, I used populations of a common tree species of the Guiana Shield - Eperua falcata (Fabaceae) - to study how neutral and adaptive processes shape the distribution of genetic diversity across forest landscapes characterized by local micro-habitat patchiness. I asked three main questions by combining both phenotypic (quantitative genetics) and molecular (population genetics) approaches: 1) How is the genetic diversity structured in forest landscapes of French Guiana? 2) Which evolutionary drivers are relevant to explain the structure of genetic diversity at local scale? 3) Does local adaptation contribute to structure genetic diversity within continuous populations?
En forêt tropicale humide Amazonienne, les facteurs gouvernant l'évolution des espèces d'arbres restent peu connus et continuellement débattus. En particulier, les micro-variations environnementales attirent beaucoup d'attention car elles induisent de profondes modifications de structure et composition des communautés. Les variations micro-environnementales associées à la topographie ont couramment été évoquées comme facteur de radiations adaptatives chez les espèces d'arbres. Cependant, l'hypothèse de l'adaptation locale n'a jamais été testée au niveau intra-spécifique chez les arbres de forêt amazonienne alors que l'on sait que la diversité génétique des arbres tropicaux est couramment structurée à faibles échelles spatiales par des processus neutres (en particulier du fait de restrictions de flux de gènes). Dans cette étude, j'ai étudié le processus de différentiation génétique d'une espèce d'arbre (Eperua falcata, Fabaceae) dans les paysages forestiers de Guyane française grâce à la combinaison d'une approche phénotypique (génétique quantitative) et d'une approche moléculaire (génétique des populations). Je me suis attachée à répondre à trois questions principales : 1) Comment se distribue la diversité génétique dans les paysages forestiers de Guyane française ? 2) Quelles forces évolutives sont impliquées dans le processus de différentiation génétique à faible échelle spatiale ? 3) Est-ce que le processus d'adaptation locale contribue à structurer la diversité génétique à faible échelle spatiale ?
https://tel.archives-ouvertes.fr/tel-00967318

NNT : 2013LORR0188
tel-00967318
https://tel.archives-ouvertes.fr/tel-00967318
https://tel.archives-ouvertes.fr/tel-00967318/document
https://tel.archives-ouvertes.fr/tel-00967318/file/THESE_Louise_Brousseau.pdf

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
ISSN: 0029-8549

hal-01086788
https://hal-agroparistech.archives-ouvertes.fr/hal-01086788
DOI : 10.1007/s00442-008-1269-6

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : Key message Molecular markers were used for paternity recovery in a maritime pine (Pinus pinasterAit.) polycross trial, facilitating forward selection. Different breeding strategies for seed orchard establishment were evaluated by comparing genetic gains and diversity. This work opens up new perspectives in maritime pine breeding.Context Polycross mating designs are widely used in forest tree breeding to evaluate parental breeding values for backward selection. Alternatively, polycross progeny trials may be used to select the best trees on the basis of individual breeding values and molecular pedigree analysis.Aims This study aimed to test such a forward selection strategy for the maritime pine breeding program.Methods In a maritime pine polycross trial, progeny with higher breeding values for growth and stem straightness was first preselected with or without relatedness constraints. After paternity recovery, the preselected trees were ranked on the basis of their breeding values, estimated from the recovered full pedigree. Finally, the best candidates were selected with three different strategies (forward, backward, mixed) and three levels of coancestry constraints to establish a virtual clonal seed orchard.Results Complete pedigrees were successfully recovered for most of the preselected trees. There was no major difference in expected genetic gains between the two preselection strategies which differed for relatedness constraints. Genetic gains were slightly higher for forward selection than for classical backward selection.Conclusion This seminal study opens up new perspectives for using forward selection within the French maritime pine breeding program.
ISSN: 1932-6203

hal-01601804
https://hal.archives-ouvertes.fr/hal-01601804
DOI : 10.1371/journal.pone.0049990
PRODINRA : 391860

Éditeur(s) : Londres : John Stockolale
Siècle(s) traité(s) : 18
Droits : Domaine public
Provenance : Archives départementales de Guadeloupe
Permalien : http://www.manioc.org/patrimon/ADG17064
ADG17064

Résumé : Arbol de hasta 6 m de alto con copa redonda, espinas largas y más bien flexibles. Hojas de 7 a 10 cm, agudas a acuminadas; pecíolo anchamente alado. Flores axilares de tamaño mediano, blancas. Fruto de 7 a 8 cm de diámetro, globoso, algo aplanado en el ápice, con 10 a 12 segmentos; pulpa ácida.
Arbre pouvant atteindre 6 m de haut, à cime arrondie, avec des épines longues et plutôt souples. Feuilles de 7 à 10 cm, aiguës à acuminées; pétiole en forme d’aile prononcée. Fleurs axillaires de taille moyenne, blanches. Fruit de 7 à 8 cm de diamètre, de forme arrondie, un peu aplati au sommet, avec 10 à 12 segments; pulpe acide.
Tree, up to 10 m tall with slender thorns. Leaf blade 7-20 cm x 7 cm; widely winged petiole; flowers axillary, white 4 cm; fruit, globose, 7-8 cm in diameter, somewhat flat at the top, peel thick, rough and strongly aromatic, pulp acidic and bitter, seeds numerous.
Nativa de Asia, cultivada en regiones tropicales y subtropicales.
Originaire d’Asie, cultivée dans des régions tropicales et subtropicales.
Native to Asia, cultivated in tropical and subtropical regions.

http://www.tramil.net/fototeca/plant133

Résumé : Cette these etudie les effets de la conversion de la foret tropicale en parcelles agricoles, sur les emissions de n2o par les sols. Ce travail est realise a l’echelle du cycle cultural sur le dispositif experimental de combi (littoral guyanais), a l’aide de mesures in situ et de simulations (modele noe) des flux de n2o. La foret tropicale a ete comparee a des parcelles de foret converties en terres agricoles par la methode ‘chop-and-mulch’. La methode de deforestation ‘chop-and-mulch’ associe coupe mecanique de la vegetation, broyage puis enfouissement des residus forestiers dans le sol. Les terres agricoles etaient soient des parcelles de prairie non paturee soient des parcelles cultivees (maïs fertilise/soja) conduites en semis conventionnel (semis apres travail du sol, sans plante de couverture) ou en semis direct (sans travail du sol, avec plantes de couverture).Les principaux resultats de cette etude sont : le sol de la foret tropicale de combi est un faible emetteur de n2o ; la conversion par la methode ‘chop-and-mulch’ de cette foret en prairie ne conduit pas a une augmentation significative des emissions de n2o entre le 19eme et le 31eme mois suivant la conversion ; la conversion de la foret en parcelles cultivees induit une augmentation significative des emissions de n2o due a la fertilisation et a la modification des parametres edaphiques (densite apparente, temperature, humidite volumique) ; la technique sans travail du sol n’engendre pas de flux de n2o significativement plus eleves que la technique avec travail du sol ; l’introduction du phenomene d’hysterese hydrique dans le modele noe presente un reel potentiel pour l’estimation des emissions de n2o in situ.
This study investigates the effects of the conversion of tropical forest to cultivation on soil n2o emissions. The study was carried out over a complete crop cycle at the experimental site combi (french guianese coast). Nitrous oxide fluxes were obtained in the field and by conducting simulations with the noe model. Undisturbed tropical rainforest was compared to rainforest that had been converted to agricultural land using the ‘chop-and-mulch’ method. The ‘chop-and-mulch’ method is a fire-free method used for vegetation clearing combining the mechanical felling of trees with the mulching of small vegetation. Agricultural land included either mowed grassland or soybean/fertilised maize crop rotation. For croplands the two cultivation practices employed were: conventional seeding (using an offset disc harrow, without cover plants) or direct seeding (no till, with cover plants).The main results of this study are: rainforest soil at combi produced low n2o emissions; rainforest converted to mowed grassland using the 'chop-and-mulch’ method did not lead to a significant increase in n2o emissions between the 19th and 31st months after conversion; the conversion of rainforest to croplands induced a significant increase in soil n2o emissions due to the application of fertiliser and the modification of soil parameters (bulk density, temperature, volumetric moisture); n2o emissions from agricultural practices with no-till were no higher than those produced by conventional agricultural practices using an offset disc harrow; and, the introduction of an hydric hysteresis into the noe model constitutes a promising improvement to estimate in situ n2o emissions.

http://www.theses.fr/2013AGUY0610/document

Éditeur(s) : [S.l.] : Murray
Siècle(s) traité(s) : 15
Droits : Domaine public
Provenance : Université des Antilles. Service commun de la documentation
Permalien : http://www.manioc.org/patrimon/HASH2cabbb39c250663de04713
HASH2cabbb39c250663de04713

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : In habitat mosaics, plant populations face environmental heterogeneity over short geographical distances. Such steep environmental gradients can induce ecological divergence. Lowland rainforests of the Guiana Shield are characterized by sharp, short-distance environmental variations related to topography and soil characteristics (from waterlogged bottomlands on hydromorphic soils to well-drained terra firme on ferralitic soils). Continuous plant populations distributed along such gradients are an interesting system to study intrapopulation divergence at highly local scales. This study tested (1) whether conspecific populations growing in different habitats diverge at functional traits, and (2) whether they diverge in the same way as congeneric species having different habitat preferences. Phenotypic differentiation was studied within continuous populations occupying different habitats for two congeneric, sympatric, and ecologically divergent tree species (Eperua falcata and E. grandiflora, Fabaceae). Over 3000 seeds collected from three habitats were germinated and grown in a common garden experiment, and 23 morphological, biomass, resource allocation and physiological traits were measured. In both species, seedling populations native of different habitats displayed phenotypic divergence for several traits (including seedling growth, biomass allocation, leaf chemistry, photosynthesis and carbon isotope composition). This may occur through heritable genetic variation or other maternally inherited effects. For a sub-set of traits, the intraspecific divergence associated with environmental variation coincided with interspecific divergence. The results indicate that mother trees from different habitats transmit divergent trait values to their progeny, and suggest that local environmental variation selects for different trait optima even at a very local spatial scale. Traits for which differentiation within species follows the same pattern as differentiation between species indicate that the same ecological processes underlie intra- and interspecific variation.
ISSN: 0305-7364

hal-01032430
https://hal.archives-ouvertes.fr/hal-01032430
DOI : 10.1093/aob/mct176

Résumé : Planta acaulescente o con tallo corto, estolonífera. Hojas lanceoladas, de 30 a 60 cm, largo-acuminadas, espinoso-dentadas. Inflorescencia en escapo de hasta 1.2 m con brácteas lanceoladas o aovadas, agudas; flores amarillas de 2.5 cm de longitud en racimos densos de 10 a 30 cm. Cápsulas (fruto) dehiscentes, con semillas negras.
Plante sans tige apparente ou à tige courte, stolonifère. Feuilles lancéolées, longues de 30 à 60 cm, terminées en pointe fine, épino-dentées. Stipe pouvant atteindre 1,2 m, grappes denses de 10 à 30 cm, bractées lancéolées ou ovées, en pointe.Fleurs jaunes de 2,5 cm de longueur en grappes denses de 10 à 30 cm. Fruit: capsule déhiscente; graines noires ailées.
Acaulescent or short-stemmed stoloniferous plant.  Leaves lanceolate, 30-60 cm in length,  long-acuminate, spiny-serrate.  Inflorescence on scape of up to 1.2 m long, with sharp lanceolate or ovate bracts; yellow flowers, 2.5 cm long, in dense 10-30 cm long racemes.  Dehiscent capsules (fruit), with black seeds.
Oriunda del Mediterráneo, ampliamente cultivada en los trópicos y subtrópicos
Originaire du bassin méditerranéen, largement cultivée en milieu tropical et subtropical.
Native to the Mediterranean, widely cultivated in the tropics and subtropics

http://www.tramil.net/fototeca/plant14

Résumé : Arbolito de 6 a 8 m, ramas jóvenes hirsutas. Hojas corto-pecioladas u obovado-oblongas de 15 a 30 cm, abruptamente acuminadas, redondeadas u obtusas en la base. Inflorescencia pequeña, cauliflora; flores largamente pecioladas; cáliz rosado, de 6-7 mm; pétalos amarillos. Fruto glabro, ovoide-oblongo, gradualmente atenuado en el ápice, 10-sulcado, los surcos irregularmente rugosos-tuberculados; semillas ovoideas.
Petit arbre de 6 à 8 m, branches jeunes hirsutes. Feuilles à court pétiole ou ovées-oblongues de 15 à 30 cm, se terminant brusquement en pointe, base arrondie, ou obtuse. Inflorescence petite, caulinaire; fleurs à long pétiole; calice rosé, de 6-7 mm; pétales jaunes. Fruit glabre, ovoïde-oblongue, dont l’extrémité s’affine graduellement, avec 10 sillons irrégulièrement rugueux-tuberculés, pulpe blanche sucrée; graines ovoïdes.
Small tree, 6- 8 (-12-14) m high.  Leaf, alternate, simple, entire, sinuate, petiole 1-2 cm, blades obovate-elliptic to oblong elliptic, 16-40 x 4.5-13 cm, base rounded to obtuse, apex acute; inflorescence axillary, 1-many flowered, clustered cymes, cauliflorous; petals white 4-4.5 mm long; fruit a glabrous, ellipsoid, leathery berry, 10-20 x 8-10 cm wide, ripening green, yellow, red or purple; seeds brown, ovoid or elliptic, 2-4x1.2-2 cm long with a sweet surrounding pulp.
Nativa de Mesoamérica y Sudamérica, cultivada ampliamente en los trópicos.
Originaire d’;Amérique centrale et d’;Amérique du sud, abondamment cultivée sous les tropiques.
Native to Middle and South America, widely cultivated in tropical r

http://www.tramil.net/fototeca/plant347

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
1. Our understanding of the contribution of interspecific interactions to functional diversity in nature lags behind our knowledge of spatial and temporal patterns. Although two-species mutualisms are found in all types of ecosystems, the study of their ecological influences on other community members has mostly been limited to third species, while their influence on entire communities remains largely unexplored. 2. We hypothesized that mutualistic interactions between two respective ant species and an epiphyte mediate the biological traits composition of entire invertebrate communities that use the same host plant, thereby affecting food webs and functional diversity at the community level. 3. Aechmea mertensii (Bromeliaceae) is both a phytotelm ('plant-held water') and an ant-garden epiphyte. We sampled 111 bromeliads (111 aquatic invertebrate communities) associated with either the ant Pachycondyla goeldii or Camponotus femoratus. The relationships between ants, bromeliads and invertebrate abundance data were examined using a redundancy analysis. Biological traits information for invertebrates was structured using a fuzzy-coding technique, and a co-inertia analysis between traits and abundance data was used to interpret functional differences in bromeliad ecosystems. 4. The vegetative traits of A. mertensii depended on seed dispersion by C. femoratus and P. goeldii along a gradient of local conditions. The ant partner selected sets of invertebrates with traits that were best adapted to the bromeliads' morphology, and so the composition of the biological traits of invertebrate phytotelm communities depends on the identity of the ant partner. Biological traits suggest a bottom-up control of community structure in C. fenaoratus-associated phytotelmata and a greater structuring role for predatory invertebrates in P. goeldii-associated plants. 5. This study presents new information showing that two-species mutualisms affect the functional diversity of a much wider range of organisms. Most biological systems form complex networks where nodes (e.g. species) are more or less closely linked to each other, either directly or indirectly, through intermediate nodes. Our observations provide community-level information about biological interactions and functional diversity, and perspectives for further observations intended to examine whether large-scale changes in interacting species/community structure over broad geographical and anthropogenic gradients affect ecosystem functions.
Functional Ecology

hal-01096909
https://hal-agroparistech.archives-ouvertes.fr/hal-01096909
DOI : 10.1111/j.1365-2435-2011.01863.x

Résumé : Hierba o arbusto densamente ramificado. Hojas con pecíolo delgado, solitarias o en pares, ovadas u ovado-lanceoladas, ápice acuminado. Dos flores o más en cada nudo, rara vez una; cáliz truncado o con lóbulos diminutos; corola blanco-verdosa o blanco amarillenta. Fruto rojo, de 1.5 a 3 cm de diámetro, elipsoide-lanceolado o lanceolado, con ápice agudo. Semillas cremosas a amarillentas. Especie muy elastica con una gran cantidad de cultivares que poseen una gran diversidad de forma en sus frutos.
Herbe ou arbuste à ramifications denses. Feuilles avec pétiole fin, solitaires ou par paires, ovalées ou ovalées-lancéolées, acuminées. Deux fleurs ou plus sur chaque noeud, rarement une; calice tronqué ou à très petits lobes; corolle blanche-verdâtre ou blanche-jaunâtre. Fruit rouge, de 1,5 à 3 cm de diamètre, ellipsoïde-lancéolé ou lancéolé, acuminé. Graines de couleur crème à jaunâtre. Espèce très élastique par une grande quantité de cultivars possédant une grande variété de formes de fruits.
Annual shrub densely branching.  Leaf with thin petiole, either single or in pairs, ovate to ovate-lanceolate, with acuminate tip; flowers solitary or two or moreper node, 5-petals, whitish-green or whitish-yellow; fruit 1.5- 3.5 cm in diameter, ellipsoid-lanceolate or lanceolate with acute tip, crinkled, red, green, yellow or orange; seeds cream or yellowish.
Originaria de América tropical. Cultivada en zonas tropicales y templadas.
Originaire d';Amérique tropicale. Cultivée dans les zones tropicales et tempérées.
Tropical America.  Cultivated in regions with tropical and moderate climates.

http://www.tramil.net/fototeca/plant90

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : The analysis of fine-scale spatial genetic structure (FSGS) within populations can provide insights into eco-evolutionary processes. Restricted dispersal and locally occurring genetic drift are the primary causes for FSGS at equilibrium, as described in the isolation by distance (IBD) model. Beyond IBD expectations, spatial, environmental or historical factors can affect FSGS. We examined FSGS in seven African and Neotropical populations of the late-successional rain forest tree Symphonia globulifera L. f. (Clusiaceae) to discriminate the influence of drift-dispersal vs. landscape/ecological features and historical processes on FSGS. We used spatial principal component analysis and Bayesian clustering to assess spatial genetic heterogeneity at SSRs and examined its association with plastid DNA and habitat features. African populations (from Cameroon and São Tomé) displayed a stronger FSGS than Neotropical populations at both marker types (mean Sp = 0.025 vs. Sp = 0.008 at SSRs) and had a stronger spatial genetic heterogeneity. All three African populations occurred in pronounced altitudinal gradients, possibly restricting animal-mediated seed dispersal. Cyto-nuclear disequilibria in Cameroonian populations also suggested a legacy of biogeographic history to explain these genetic patterns. Conversely, Neotropical populations exhibited a weaker FSGS, which may reflect more efficient wide-ranging seed dispersal by Neotropical bats and other dispersers. The population from French Guiana displayed an association of plastid haplotypes with two morphotypes characterized by differential habitat preferences. Our results highlight the importance of the microenvironment for eco-evolutionary processes within persistent tropical tree populations.
ISSN: 1932-6203

hal-01608324
https://hal.archives-ouvertes.fr/hal-01608324
DOI : 10.1371/journal.pone.0182515
PRODINRA : 403154
PUBMED : 28771629

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
Chelonanthus alatus is a bat-pollinated, pioneer Gentianaceae that clusters in patches where still-standing, dried-out stems are interspersed among live individuals. Flowers bear circum-floral nectaries (CFNs) that are attractive to ants, and seed dispersal is both barochorous and anemochorous. Although, in this study, live individuals never sheltered ant colonies, dried-out hollow stems--that can remain standing for 2 years--did. Workers from species nesting in dried-out stems as well as from ground-nesting species exploited the CFNs of live C. alatus individuals in the same patches during the daytime, but were absent at night (when bat pollination occurs) on 60.5% of the plants. By visiting the CFNs, the ants indirectly protect the flowers--but not the plant foliage--from herbivorous insects. We show that this protection is provided mostly by species nesting in dried-out stems, predominantly Pseudomyrmex gracilis. That dried-out stems remain standing for years and are regularly replaced results in an opportunistic, but stable association where colonies are sheltered by one generation of dead C. alatus while the live individuals nearby, belonging to the next generation, provide them with nectar; in turn, the ants protect their flowers from herbivores. We suggest that the investment in wood by C. alatus individuals permitting still-standing, dried-out stems to shelter ant colonies constitutes an extended phenotype because foraging workers protect the flowers of live individuals in the same patch. Also, through this process these dried-out stems indirectly favor the reproduction (and so the fitness) of the next generation including both their own offspring and that of their siblings, all adding up to a potential case of inclusive fitness in plants.
ISSN: 1932-6203

hal-00825845
https://hal.archives-ouvertes.fr/hal-00825845
https://hal.archives-ouvertes.fr/hal-00825845/document
https://hal.archives-ouvertes.fr/hal-00825845/file/Dejean2011_Inherited.pdf
DOI : 10.1371/journal.pone.0018071