Bryological and Lichenological Section/ABLS
Korpelainen, Helena , Pohjamo, Maria , Kostamo, Kirsi , Virtanen, Viivi .
Dispersal and gene flow in aquatic bryophytes occurring in a connected lake system.
Population genetic characteristics of three moss species were examined in Finland (63˚N 28˚E) in a water system composed of five small lakes, which are connected through streams and which eventually flow into a large lake. The species included in the study are Fontinalis antipyretica and F. hypnoides (Fontinalaceae), and Calliergon megalophyllum (Campyliaceae). F. antipyretica and F. hypnoides are dioecious while C. megalophyllum is monoecious. Sprophyte production is rare in all three species, and reproduction generally takes place through vegetative propagation. We specifically aimed to analyze genetic diversity and the level of gene flow using neutral molecular markers, and to examine the efficiency of dispersal which is expected to occur mainly by shoot fragmentation through water. In general, dispersal resulting in colonization and gene flow into existing populations is very important for both the persistence and genetic success of a species.
The lakes and connecting streams were mapped for the presence of the species by diving and raking, and samples were collected. The genetic analysis used to reveal DNA polymorphisms was based on polymerase chain reaction and involved the amplification of DNA sequences with several ISSR (inter simple sequence repeats) primers. ISSRs exploit the highly polymorphic nature of simple sequence repeats of DNA, detect multiple loci per primer in most cases, and conveniently generate a large set of genetic markers. The resulting fragment patterns were analyzed using an automated sizing system, which results in quick and reliable sample comparisons. The presence of genetic variation and the lack of considerable differentiation between samples originating from different lakes support the idea that dispersal and gene flow take place quite effectively through water.
1 - Finnish Natural History Museum, P.O. Box 7, FI-00014 Helsinki, , Finland
2 - University of Helsinki, Department of Applied Biology, P.O. Box 27, Helsinki, FIN-00014, Finland
Presentation Type: Paper
Location: Ballroom 3 (Cliff Lodge)
Date: Tuesday, August 3rd, 2004
Time: 4:30 PM