Anttila, Carina K. , King, R. Andrew .
Phylogeography of Spartina alterniflora from its native Atlantic coast range, and the origins of major Pacific coast introductions.
In San Francisco Bay, hybridization between invasive smooth cordgrass, Spartina alterniflora, and native California cordgrass, Spartina foliosa, is threatening the survival of the native species and leading to the loss of open mudflats important for shorebirds, marine life, flood control, and navigation. Previous studies identified three single-nucleotide, polymorphic sites within the chloroplast DNA tRNALeu1 intron which vary between the native and invasive species and provide useful markers for the study of the patterns of hybridization occurring between these two species. Here we take advantage of these markers to complete a detailed molecular phylogeography of S. alterniflora in its native range along the Atlantic and Gulf coasts of the United States, sampling 104 individuals representing 39 populations from Massachusetts to Florida. cpDNA analysis revealed the existence of three major groups, each represented by a different haplotype, concentrating in different but overlapping geographical regions: TAA to the north, TAT in the central region, and CAT to the south. All three haplotypes occur in the S. alterniflora of San Francisco Bay. Although dominant in different regions, significant overlaps occur, and we were unable to identify the likely sources of introduction into San Francisco Bay from these data. Analysis of a nuclear ribosomal DNA spacer region also revealed a north-south divison of cytotypes, but distinguished only two major groups. The phylogeographical patterns revealed by tRNALeu1 intron haplotypes are broadly consistent with those determined through morphological analysis and RAPD studies, and also generally agree with the locations of phylogeographical breaks for other species in these regions.
Log in to add this item to your schedule
1 - University of Joensuu, Biological Station, Joensuu, 80101, Finland
2 - Cardiff University, Cardiff School of Bioscience, Biomedical Science Building, Museum Avenue, Cardiff, CF103US, UK
San Francisco Bay
Presentation Type: Poster:Posters for Topics
Location: Event Tent/Cliff Lodge
Date: Monday, July 27th, 2009
Time: 5:30 PM