Tracing the origin of Gulf Coast Phragmites (Poaceae): A story of long-distance dispersal and hybridization

• Premise of the study: Long-distance dispersal can affect speciation processes in two opposing ways. Dispersal can promote geographic isolation or it can bring together geographically distant and distantly related genotypes, thus counteracting local differentiation. We used the Gulf Coast of North...

Full description

Bibliographic Details
Published in:American Journal of Botany
Main Authors: Lambertini C., Mendelssohn I. A., Gustafsson M. H. G., Olesen B., Riis T., Sorrell B. K., Brix H.
Other Authors: C. Lambertini, I.A. Mendelssohn, M.H.G. Gustafsson, B. Olesen, T. Rii, B.K. Sorrell, H. Brix
Format: Article in Journal/Newspaper
Language:English
Published: WILEY 2012
Subjects:
Gene flow
Gulf coast
Hybridization
Introgression
Invasion
Long-distance dispersal
Phragmites australi
Phragmites mauritianu
Amplified Fragment Length Polymorphism Analysi
Biological Evolution
Demography
Genetic Marker
Genetic Variation
Genetic
Poaceae
Species Specificity
Settore BIO/02 - Botanica Sistematica
Antarc*
Antarctica
Online Access:http://hdl.handle.net/2434/923162
https://doi.org/10.3732/ajb.1100396
Description
Summary:• Premise of the study: Long-distance dispersal can affect speciation processes in two opposing ways. Dispersal can promote geographic isolation or it can bring together geographically distant and distantly related genotypes, thus counteracting local differentiation. We used the Gulf Coast of North America (GC), a "hot spot" of reed diversity and evolutionary dynamics, as a model system to study the diversification processes within the invasive, cosmopolitan, polyploid grass Phragmites. • Methods: Genetic diversity was studied using collections representing all species of the genus and from all continents (except Antarctica). A range of molecular markers, including chloroplast and nuclear sequences, microsatellites, and AFLPs, was analyzed to detect DNA variation from the population to the species level and to infer phylogenetic relationships across continents. • Key results: An interspecific hybrid, Phragmites mauritianus × P. australis, and four P. australis cp-DNA haplotypes from Africa, Europe, and North America have been dispersed to the GC and interbreed with each other. • Conclusions: Long-distance dispersal and weak breeding barriers appear to be recurring phenomena, not only in the GC, but worldwide. We present data strongly suggesting that interspecific hybridization and introgression among different Phragmites species take place and appear to have contributed significantly to the diversification processes within the genus. Hence, the application of traditional species concepts within Phragmites might be inappropriate. © 2012 Botanical Society of America.

Similar Items