Abstract Detail

Population Genetics

Carter, Christy T [1], Ballard Jr, Harvey E [2], Ungar, Irwin A [2].

Soil seed banks can be less genetically diverse than any aboveground population: An investigation of three annual halophyte species in an inland salt marsh through time.

It has been documented that soil seed banks are a collection of genetic information over many years past and, at any given point in time, are reported to be more genetically diverse than any aboveground population for a single species. Using Inter-Simple Sequence Repeat (ISSR) analysis, genetic diversity of three annual halophytes (Atriplex prostrata, Salicornia depressa, and Spergularia salina) from an inland salt marsh was investigated. For each of these autogamously reproducing species, genetic diversity was compared within and among three cohorts that represented populations from 1981, 1998, and the persistent seed bank of 2000. Genetic variation was examined using three ISSR primers on thirty samples representing thirty individuals for each cohort of each species, with one exception for the 1981 cohort of S. depressa where nine samples were used but still captured 98.5% of the variation. For each species, Analysis of Molecular Variance (AMOVA) indicated that cohorts from 1981, 1998, and the persistent seed bank of 2000 were significantly different. Turnover in genetic composition was evident over the 17-y period between the 1981 and 1998 cohorts as evidenced by the Principal Coordinates Analysis (PCoA). Above- and belowground cohorts also showed a high degree of separation. Percent polymorphic loci showed that the 2000 seed banks of S. salina and S. depressa were less diverse than either of their respective aboveground cohorts from 1981 or 1998. In fact, the seed bank of S. salina was monomorphic. Alternatively, the persistent seed bank from 2000 of A. prostrata was more diverse than the 1981 or 1998 aboveground cohorts. There was an increase in genetic diversity from 1981 to 1998 for S. salina and A. prostrata, but a decrease in diversity for S. depressa. Our findings show that seed banks do not always function as a long-term storehouse of genetic information. They can be less genetically diverse than any one population. Genetic diversity may increase or decrease for any given population over time across multiple species in a single habitat. More multi-year or cross-decade investigations on seed banks and aboveground vegetation in annual wetland species, especially in extreme habitats such as inland salt marshes, are needed. (Published in 2016 as “Genetic variability of three annual halophyte species in an inland salt marsh through time.” In: Sabkha Ecosystems Vol. V, The Americas. Tasks for Vegetation Science Vol. 48. (Khan, Boër, Ozturk, Clüsener-Godt, Gul, and Breckle, eds.) Springer International Publishing, Dordrecht, The Netherlands.)

1 - Wingate University, Department of Biology, 216 Cedar Street, Bridges Bldg. 112, Wingate, NC, 28174, USA
2 - Ohio University, Department of Environmental and Plant Biology, 315 Porter Hall, Ohio University, Athens, OH, 45701, USA

Keywords:
Atriplex prostrata
Genetic diversity
Salicornia depressa
soil seed banks
Spergularia salina.

Presentation Type: Poster
Session: P, Population Genetics Posters
Location: Exhibit Hall/Savannah International Trade and Convention Center
Date: Monday, August 1st, 2016
Time: 5:30 PM This poster will be presented at 5:30 pm. The Poster Session runs from 5:30 pm to 7:00 pm. Posters with odd poster numbers are presented at 5:30 pm, and posters with even poster numbers are presented at 6:15 pm.
Number: PPG005
Abstract ID:448
Candidate for Awards:None