Conserving genomic diversity in tropical trees from French Guiana

French Guiana is an overseas territory of France which harbours a tropical rainforest with a vast biodiversity, including ca. 1800 tree species. This forest suffers pressure from mining, climate change, and logging in the permanent forest domain. Conserving the rainforest and achieving sustainable timber production to meet the demands of a growing human population is a considerable challenge. We present an overview of our ongoing research in ecological and conservation genomics in several tree species of French Guiana. We showed how tree species complexes of the genera Symphonia and Eschweilera are adapted to microenvironmental conditions relating to moisture, soil chemistry, and light. In the most harvested timber tree Dicorynia guianensis we use estimates of regional and local population genetic structure, population demographic histories, and genomic signatures of adaptation to derive sustainable management guidelines under future climates. We have used a combination of microsatellites, genomic, and transcriptomic approaches to characterise the genetic diversity of the highly endangered Aniba rosaeodora, and identify genes implicated in the production of rosewood essential oil. We also present tools under development for simplified field delimitation of morphologically similar species of Eschweilera in view of sustainable harvesting of common species while conserving rare related species

Soil variation response is mediated by growth trajectories rather than functional traits in a widespread pioneer Neotropical tree

1. Trait-environment relationships have been described at the community level across tree species. However, whether interspecific trait-environment relationships are consistent at the intraspecific level is yet unknown. Moreover, we do not know how consistent is the response between organ vs. whole-tree level. 2. We examined phenotypic variability for 16 functional leaf (dimensions, nutrient, chlorophyll) and wood traits (density) across two soil types, Ferralitic Soil (FS) vs. White Sands (WS), on two sites for 70 adult trees of Cecropia obtusa Trécul (Urticaceae) in French Guiana. Cecropia is a widespread pioneer Neotropical genus that generally dominates early successional forest stages. To understand how soil types impact resource use through the processes of growth and branching, we examined the architectural development with a retrospective analysis of growth trajectories. We expect soil types to affect both, functional traits in relation to resource acquisition strategy as already described at the interspecific level, and growth strategies due to resource limitations with reduced growth on poor soils. 3. Functional traits were not involved in the soil response, as only two traits -leaf residual water content and K content-showed significant differences across soil types. Soil effects were stronger on growth trajectories, with WS trees having the slowest growth trajectories and less numerous branches across their lifespan. 4. The analysis of growth trajectories based on architectural analysis improved our ability to characterise the response of trees with soil types. The intraspecific variability is higher for growth trajectories than functional traits for  C. obtusa, revealing the complementarity of the architectural approach with the functional approach to gain insights on the way trees manage their resources over their lifetime. Soil-related responses of Cecropia functional traits are not the same as those at the interspecific level, suggesting that the effects of the acting ecological processes are different between the two levels. Apart from soil differences, much variation was found across sites, which calls for further investigation of the factors shaping growth trajectories in tropical forests

Timber tracking of Jacaranda copaia from the Amazon forest using DNA fingerprinting

We investigated the utility of nuclear and cytoplasmic single nucleotide polymorphism (SNP) markers for timber tracking of the intensively logged and commercialized Amazonian tree Jacaranda copaia. Eight hundred and thirty-two trees were sampled (cambium or leaves) from 38 sampling sites in Bolivia, Brazil, French Guiana, and Peru. A total of 128 SNP markers (113 nuclear, 11 chloroplastic, and 4 mitochondrial) were used for genotyping the samples. Bayesian cluster analyses were carried out to group individuals into homogeneous genetic groups for tests to self-assign groups of individuals or individuals to their population of origin. Cluster analysis based on all the SNP markers detected seven main genetic groups. Genetic differentiation was high among populations (0.484) and among genetic groups (0.415), and populations showed a strong isolation-by-distance pattern. Self-assignment testing of the groups of individuals for all loci was able to determine the population origin of all the samples (accuracy = 100%). Self-assignment tests of individuals were able to assign the origin of 94.5%–100% of individuals (accuracy: 91.7%–100%). Our results show that the use of the 128 SNP markers is suitable to correctly determine the origin of J. copaia timber, and they should be considered a useful tool for customs and local and international police

Follicle-Stimulating Hormone Receptor: Advances and Remaining Challenges

International audienc

BD CARTO : structure utilisateur METL v98 : spécifications et descriptif de contenu

Présentation des données de la BD CARTO en précisant, d'une part, les spécifications techniques du produit, et d'autre part, le descriptif de livraison de la structure utilisateur v98 du MATL. Chaque objet ou relation de la base y est décrit dans une fiche qui comprend : - En titre : le nom de la classe d'objets ou de la relation, le nom du fichier en structure utilisateur v98. - Les spécifications de l'objet ou de la relation qui sont décrites au moyen de : la définition, le type (ponctuel, linéaire ou surfacique), les relations qui concernent l'objet, ou, dans le cas d'une relation, les objets liés par cette relation et sa cardinalité, les sélections opérées sur les objets lors de la saisie. - La description des attributs et leurs valeurs pré-codées (pour les attributs à valeurs pré-codées, le nom du fichier de référence est rappelé). - Certaines précisions de saisie, quand cela s'avère nécessaire, pour une meilleure compréhension des données. - Le nom des fichiers Arc/Info ou des objets EDIGéO d'origine