Abstract Detail

Conservation Biology

Ashley, Mary V. [1].

Asexual Reproduction and the Persistence of Threatened Plant Populations.

The majority of flowering plants have the capability of vegetative reproduction and clonal growth, including many threatened and endangered species. Conservation of such species should include characterizing clonal structure and genet diversity, because monitoring the number of ramets will not reveal the number of genets. Genet surveys generally require DNA genotyping because clonal structure can be cryptic and highly variable. Evidence from wild strawberry, Fragaria virginiana, shows that nearby populations can differ greatly in reproductive patterns and clonal diversity despite having similar ramet densities and distributions. Such cryptic clonal structure was also found in an endangered oak species, Quercus hinckleyi, where two of the four remaining populations had only seven genotypes among 58 censused ramets. Increased asexual reproduction in threatened species may also be self-reinforcing, by further limiting the opportunities for sexual reproduction. Large clone sizes will increase self-pollination in self-compatible species because many flowers will belong to the same clone. For self-incompatible species, asexual reproduction reduces the number of compatible mates. At the extreme, populations of self-incompatible species will become sexually extinct when they are comprised of a single clone. We found this to be case for populations of Asclepias lanuginosa in fragmented prairie remnants; several populations were monoclonal with a complete shift in mode of reproduction from sexual to asexual. Failure to consider clonal identity and diversity may also hamper restoration efforts; microsatellite genotyping of the endangered Hawaiian endemic Solanum nelsonii revealed moderate levels of clonality at a remnant natural site but only a single clone at a site where the species had been reintroduced for conservation management. Clonal growth may benefit conservation efforts by allowing populations to persist in marginal or changing environments, and by preserving genotypic diversity and heterozygosity under conditions where sexual reproduction cannot occur. However, conservation efforts that monitor clonal structure and manage populations to increase genotypic diversity will enhance prospects for sexual reproduction and improve long-term prospects for species persistence.

1 - University Of Illinois At Chicago, 845 W. Taylor St., Chicago, IL, 60607, USA

Keywords:
asexual reproduction
cloning
conservation
Genetic diversity
Asclepias lanuginosa
Quercus hinckleyi
Solanum.

Presentation Type: Oral Paper
Session: 48, Conservation Biology II
Location: 204/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 3:00 PM
Number: 48006
Abstract ID:798
Candidate for Awards:None