IANNONE Leopoldo Javier
congresos y reuniones científicas
6th International Conference on Comparative Biology of Monocotyledons
GIUSSANI L.M.; SABENA F.R..; CELSI, C.; IANNONE L.J.
Congreso; Conference on Comparative Biology of Monocotyledons ? Monocots VI; 2018
Universdad Federal de Rio Grande del Norte
Poa is one out of 22 genera of grasses where dioecy is expressed. Reproductive system in the American Poa evolved during the Late Miocene in Northern and Southern hemispheres, independently. Dioecy appeared associated with geological episodes such as Andean mountain, climatic variation and biogeographic events. The monophyletic section Dioicopoa originated during Pliocene to Early Pleistocene in SSouth America; characterized by a rapid evolutionary radiation. The section comprises ca. 30 species; speciation within Dioicopoa accompanied cycles of glaciations giving rise to the extensive morphological variation associated to particular climatic and ecological characteristics. Coastal dunes are dynamic ecosystems due to aeolian formation and rapid modification. They offer an opportunity for speciation processes and the selection of genotypes that lead to endemisms. Through morphological and molecular studies in a widely distributed species (Poa lanuginosa) and two narrow endemisms (Poa bergii and Poa schizantha), quantitative and qualitative changes are detected among populations that would explain adaptative and evolutionary processes in coastal dunes. The incidence of symbiont endophytic fungi of Epichloë and their association with these species are evaluated as coevolutionary processes or horizontal endophyte transfer. Genetic diversity of dune populations of Poa and endophytes, and symbiotic interaction are studied in the dynamic coastal environments.