Ecological genomics of local adaptation in inundation gradient of Amazonian floodplain forests

Abstract

Population heterogeneity has fundamental implications for adaptative phenotype fitness along environmental gradients. Genomic information in combination with functional attributes information, like ecophysiological tolerances and local adaptation, as well as to ecological niches, are of great importance for understanding species distribution in natural environment, both at present as in future scenarios. In Amazon riparian forests, plant distribution is mainly determined by species tolerance to varying levels of flooding. Here, we propose a study of the local adaptation along the flooding gradient of two plant species occurring at the riparian zone of the Cupari River, west Pará, by the use of structural and functional genomic tools and greenhouse experiments. Specifically, we will study ecological genomics of local adaptation to the flooding gradient of the abundant understory herb, Ischnosiphon puberulus (Marantaceae), and of a widely distributed riparian tree, Macrolobium bifolium (Fabaceae). We will use high throughput sequencing methodologies, of both DNA and RNA, and we will conduct genetic analysis to characterize differential expression in seedlings under antagonic and stressful controlled conditions of dryness and flood; to finally compare genomic and phenotypic divergence related to natural flooding gradients. Hence, patterns from natural populations distributed along a natural environmental gradient, summed with knowledge acquired from performance in controlled experimental conditions, will be jointly analyzed through population genomic approaches, allowing the construction of spatial maps of genomic selection signatures with high resolutions. By this combined approach we will be able to advance our comprehension of local adaptation evolution, its role on global environmental change, and suggest more effective conservation and management strategies for threatened riparian populations or species. The present proposal will certainly contribute to rise regional scientific competence in the use of current molecular technologies and bioinformatics, as well as in the interpretation of genomic big data. Senior researchers' expertises involved in this proposal team will greatly enhance quality of young researchers' production from both Pará and São Paulo states, particularly in human resource generation and establishment in the Amazon region and in the growing infrastructure of high level and innovative approaches in Biological research. (AU)