Abstract Detail

Biogeography

Oliveira, Luiz Orlando de [1], Mangaravite, Erica [1], Vinson, Christina C. [1], Garcia, Magali G. [2], Carniello, Maria Antonia [3], Silva, Roberta S. [1].

Contemporary patterns of genetic diversity of Cedrela fissilis (Meliaceae) offer insight into the shaping of seasonal forests in Eastern South America.

We investigated how genetic diversity is distributed across the geographic range of Cedrela fissilis, an arboreal tree species associated with seasonal forests to gain insights into the genetic structure and biogeography of this species. A total of 250 specimens were sampled from 18 sites across the species’ range in Brazil and Eastern Bolivia and genotyped with 10 microsatellite loci. An array of complementary methods — F statistics, analyses of molecular variance (AMOVA), and clustering analyses — assessed genetic diversity, population differentiation, and structure. There were 236 alleles, with 23.6 alleles per locus on average. Most of the genetic diversity (86%) was partitioned within populations; mean expected heterozygosity and mean observed heterozygosity were 0.801 and 0.688, respectively. The 250 specimens were sorted into two Bayesian groups; there was one group for each side of the Cerrado. The populations showed varying levels of admixture, especially those located towards central Brazil. In C. fissilis, genetic diversity is structured according to geography: the Atlantic range and the Chiquitano range each harbour a genealogical lineage. Interfertility and varying levels of admixture between lineages provide strong evidence that the lineages evolved under geographic, but not genetic isolation. Admixture is of recent origin, owing to population expansion. Cedrela fissilis shares this dual pattern of distribution of genetic diversity with other phylogenetically unrelated taxa that are typically associated with seasonal forests.

1 - Federal University of Vicosa, Vicosa, MG, 36570000, Brazil
2 - Federal University of Para, Altamira, PA, 66075110, Brazil
3 - Universidade do Estado do Mato Grosso, Caceres, MT, 78200000, Brazil

Keywords:
biogeography
Microsatellites
Pleistocene Arc
Refugia
population genetics.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PBG005
Abstract ID:680
Candidate for Awards:None