Table of Contents
ISRN Ecology
Volume 2011, Article ID 501838, 13 pages
Research Article

Genetic Structure of Sympatric Sexually and Parthenogenetically Reproducing Population of Chara canescens (Charophyta)

1Department of Aquatic Ecology, Institute of Biosciences, University of Rostock, Albert-Einstein Straße 3, 18051 Rostock, Germany
2Laboratory of Evolutionary Biodemography, Max Planck Institute for Demographic Research, Konrad Zuse Straße 1, 18057 Rostock, Germany
3Department of Bioengineering, Leibniz-Institute for Agricultural Engineering Potsdam-Bornim, Max-Eyth-Allee 100, 14469 Potsdam, Germany

Received 31 January 2011; Accepted 17 March 2011

Academic Editor: W. Shi

Copyright © 2011 Ralf Schaible et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Individuals that reproduce parthenogenetically do not have to produce males and can therefore produce twice as many female offspring. With this twofold reproduction advantage of asexual reproduction, the question of how sex persists in the short term remains unresolved. In the dioecious charophyte Chara canescens, both parthenogenetically reproducing females and sexually reproducing females and males occur sympatrically at only one site in Europe: Neusiedler See-Seewinkel (Austria). By means of four nuclear species-specific microsatellite loci, we examined the interaction between coexisting sexuals and parthenogens by analysing the population structure and gene flow between both reproduction systems. Using a Bayesian assignment method, we found that the sites encompassed two genetically distinct clusters of individuals. The first cluster included genotypes of sexual individuals, which are genetically distinct from a second cluster which included parthenogenetic individuals and few sexually reproducing males, which are genetically identical to the parthenogenetic individuals. However, an analysis of the population genetic structure found no differences with respect to genotypic variation, clonal diversity, and population differentiation between the sympatric parthenogenetically and the sexually reproducing populations. The results indicated that the parthenogenetic individuals cannot outcompete the sexually reproducing individuals.