Maria Zabaleta

In this study, we explore the applicability of DNA barcoding, specifically targeting the chloroplast DNA (cpDNA) sequences, particularly the trnL (UAA) intron region, to analyze the diet of gray brocket deer. This approach offers improved taxonomic resolution and the ability to identify species with greater precision compared to traditional methods. The study was conducted in the "Reserva Natural Salus" in Uruguay, covering a range of vegetation types, where gray brocket deer coexist with other exotic ungulates. A local reference database of trnL (UAA) sequences was established, incorporating both GenBank data and sequences obtained from native species in the study area. Fecal samples were collected in summer and winter, and DNA was extracted and amplified for metabarcoding analysis in pooled samples for each season. For each sample 28,229 and 33,588 reads were obtained respectively, which together corresponded to 25 Operational Taxonomic Units (OTUs). The species Rubus ulmifolius and Schinus engleri were the most represented in the diet with 69.6 % of the summer reads, whereas in winter, 68.7 % of the reads corresponded only to Schinus engleri. These findings indicate that gray brocket deer consume species that have higher nutritional value, which may be linked to their capacity to thrive in young and productive ecosystems. This study demonstrates the feasibility of DNA barcoding for dietary analysis in gray brocket deer and provides valuable insights into their food habits in the "Reserva Natural Salus". Further improvements to increase the reference databases of native species and the exploration of additional genetic markers are recommended for enhanced species-level discrimination in dietary analysis studies. This methodology is promising for future research as diet studies have an impact on species management, habitat conservation and biodiversity conservation efforts.

Punta Ballena is the coastal southern tip of the Sierra de la Ballena, a shear zone of two tectonic plates, located at the beginning of the oceanic coast of Uruguay. Coastal rocky points are especially relevant because of their high plant richness, moreover their vegetation is endangered mainly due to the high tourist - urbanistic development of the coast. This study aims to determine the list of vascular plants occurring on Punta Ballena coastal rocky point and identify its vegetation communities. Also, to identify endemic species, threatened and of interest for conservation species; and to analyze the species historically documented for the site. Punta Ballena stands out for its remarkable species richness with 428 species, dominated by Asteraceae (82), Poaceae (82) and Fabaceae (26). Five vegetation types were found in the natural area, which allows the combination of species with different adaptations. The site supports five vulnerable species and one endangered species (IUCN), 33 priority species for conservation, two local endemisms and numerous national (14) and regional (45) endemisms. Regarding historical collections, to date Punta Ballena has suffered a loss of 14% of its species, this is likely a direct consequence of the recent urban development. From these historically documented species, we consider five of them to be locally extinct. Due to these overwhelming results, we consider the site a diversity hotspot on the Uruguayan coast. It becomes urgent to generate conservation plans that allow the maintenance of the flora and vegetation communities that are still preserved in the area.

Among semi-aquatic species of the legume genus Aeschynomene, some have the property of being nodulated by photosynthetic Bradyrhizobium lacking the nodABC genes necessary for the synthesis of Nod factors. Knowledge of the specificities underlying this Nod-independent symbiosis has been gained from the model legume Aeschynomene evenia but our understanding remains limited due to the lack of comparative genetics with related taxa using a Nod factor-dependent process. To fill this gap, we combined different approaches to perform a thorough comparative analysis in the genus Aeschynomene. This study significantly broadened previous taxon sampling, including in allied genera, in order to construct a comprehensive phylogeny. In the phylogenetic tree, five main lineages were delineated, including a novel lineage, the Nod-independent clade and another one containing a polytomy that comprised several Aeschynomene groups and all the allied genera. This phylogeny was matched with data on chromosome number, genome size and low-copy nuclear gene sequences to reveal the diploid species and a polytomy containing mostly polyploid taxa. For these taxa, a single allopolyploid origin was inferred and the putative parental lineages were identified. Finally, nodulation tests with different Bradyrhizobium strains revealed new nodulation behaviours and the diploid species outside of the Nod-independent clade were compared for their experimental tractability and genetic diversity. The extended knowledge of the genetics and biology of the different lineages sheds new light of the evolutionary history of the genus Aeschynomene and they provide a solid framework to exploit efficiently the diversity encountered in Aeschynomene legumes. Notably, our backbone tree contains all the species that are diploid and it clarifies the genetic relationships between the Nod-independent clade and the Nod-dependent lineages. This study enabled the identification of A. americana and A. patula as the most suitable species to undertake a comparative genetic study of the Nod-independent and Nod-dependent symbioses.