Hirsch et al. 2015 (Conference Paper) Dyckia

Patterns of hybridization in three sympatric species of Dyckia (Bromeliaceae) endemic from southern Brazil

Author(s):—Luiza Hirsch, Camila Zanella, Camila Melo & Fernanda Bered in Benko-Iseppon, A.M.; Alves, M. & Louzada, R. (2015) An overview and abstracts of the First World Congress on Bromeliaceae Evolution. Rodriguésia 66(2): A1-A66.

Publication:— (2015).

Abstract:—Hybridization is a powerful evolutionary force in the process of diversification of lineages and speciation. Theknowledge of this force and interspecific gene flow patterns which potentially occur in correlated species is needed tounderstand the process of maintenance of the different species. Natural hybridization between sympatric species canbe relatively common and provides a valuable tool to study the evolution of reproductive isolation barriers. Speciesthat have undergone recent adaptive radiation are highly informative to study reproductive isolation and to betterunderstand the role of drift and natural selection in the cohesion of species. Dyckia has around 145 species and is thesecond largest genus of Pitcairnioideae. In Rio Grande do Sul, the southernmost Brazilian Federal state, 28 speciesare described, of which 17 are potentially endemic. The aim of our study is to understand mechanisms of speciation,reproductive isolation and species cohesion in three sympatric endemic Dyckia species, D. elisabethae, D. hebdingiiand D. choristaminea. Dyckia elisabethae is currently classified as ?vulnerable?, Dyckia hebdingii and Dyckia choristaminea as ?endangered?. To evaluate the pattern of interspecific gene flow, we sampled two sympatric populationsand one allopatric population of D. hebdingii, totaling 250 individuals. We performed DNA extraction from all samplesand we achieved sixteen nuclear microsatellite loci successfully tested for the three populations. Three regions thatwere previously sequenced exhibited polymorphisms among all three species, suggesting differences among them.This research will elucidate the role of such differences in hybridization and the dynamics of isolation barriers. Ourprospective plan is to collect another sympatric population and two allopatric populations, referring to D. elisasbethae and D. choristaminea, in order to be used as reference samples of pure individuals of each species.

Keywords:—Bromeliaceae; Endemism; Microsatellites.