Histological characterization of resistance to different root-knot nematode species related to phenolics accumulation in Capsicum annuum

International audienc

Development and evaluation of a genome-wide Coffee 8.5K SNP array and its application for high-density genetic mapping and for investigating the origin of Coffea arabica L

Coffee species such as Coffea canephora P. (Robusta) and C. arabica L. (Arabica) are important cash crops in tropical regions around the world. C. arabica is an allotetraploid (2n = 4x = 44) originating from a hybridization event of the two diploid species C. canephora and C. eugenioides (2n = 2x = 22). Interestingly, these progenitor species harbour a greater level of genetic variability and are an important source of genes to broaden the narrow Arabica genetic base. Here, we describe the development, evaluation and use of a single-nucleotide polymorphism (SNP) array for coffee trees. A total of 8580 unique and informative SNPs were selected from C. canephora and C. arabica sequencing data, with 40% of the SNP located in annotated genes. In particular, this array contains 227 markers associated to 149 genes and traits of agronomic importance. Among these, 7065 SNPs (82.3%) were scorable and evenly distributed over the genome with a mean distance of 54.4 Kb between markers. With this array, we improved the Robusta high-density genetic map by adding 1307 SNP markers, whereas 945 SNPs were found segregating in the Arabica mapping progeny. A panel of C. canephora accessions was successfully discriminated and over 70% of the SNP markers were transferable across the three species. Furthermore, the canephora-derived subgenome of C. arabica was shown to be more closely related to C. canephora accessions from northern Uganda than to other current populations. These validated SNP markers and high-density genetic maps will be useful to molecular genetics and for innovative approaches in coffee breeding

Logiques d’appropriation et politiques de l’espace urbain : jeunes skateurs dans la ville de La Plata en Argentine

International audienceThe purpose of this article is to describe and analyse the forms of appropriation of urban space through the informal practice of skateboarding. Our hypothesis is that this pastime, which basically unites youth, is not as futile as it appears but rather signifies a political act that leads to the consideration of these protagonists as citizens. Semi-directional interviews and field observations of these stakeholders in the town of La Plata in Argentina have made it possible to complete a socio-anthropology of skateboarding and to reveal the logics of appropriating space – especially streets – which create tension with other citizens and various public institutions.L’objectif de cet article consiste à décrire et analyser les formes d’appropriation de l’espace urbain à travers la pratique informelle du skateboard. Nous posons comme hypothèse que cette pratique de loisirs, qui rassemble essentiellement des jeunes, n’est pas si futile qu’elle y paraît mais signe un acte politique qui invite à penser ces protagonistes comme des citoyens. Des entretiens semi-directifs et des observations de terrain de ces acteurs de la ville de La Plata en Argentine ont permis de réaliser une socio-anthropologie du skateboard et de déceler les logiques d’appropriation de l’espace – en particulier de la rue – qui créent des tensions avec d’autres citoyens et diverses institutions publiques

Unveiling the diet of elusive rainforest herbivores in next generation sequencing era? The tapir as a case study.

Characterizing the trophic relationships between large herbivores and the outstanding plant diversity in rainforest is a major challenge because of their elusiveness. This is crucial to understand the role of these herbivores in the functioning of the rainforest ecosystems. We tested a non-invasive approach based on the high-throughput sequencing of environmental samples using small plant plastid sequences (the trnL P6 loop) and ribosomal ITS1 primers, referred to as DNA metabarcoding, to investigate the diet of the largest neotropical herbivore, the lowland tapir. Sequencing was performed on plant DNA extracted from tapir faeces collected at the Nouragues station, a protected area of French Guiana. In spite of a limited sampling, our approach reliably provided information about the lowland tapir's diet at this site. Indeed, 95.1% and 74.4% of the plant families and genera identified thanks to the trnL P6 loop, respectively, matched with taxa already known to be consumed by tapirs. With this approach we were able to show that two families and eight new genera are also consumed by the lowland tapir. The taxonomic resolution of this method is limited to the plant family and genera. Complementary barcodes, such as a small portion of ITS1, can be used to efficiently narrow identifications down to the species in some problematic families. We will discuss the remaining limitations of this approach and how useful it is at this stage to unravel the diet of elusive rainforest herbivores and better understand their role as engineers of the ecosystem