Abstract Detail

Pteridology

Ranft, Hannah [1], Picard, Kathryn [2], Grusz, Amanda [3], Windham, Michael [4], Schuettpelz, Eric [5].

Sometimes it only takes one to tango: using natural history collections to assess the impact of asexuality in the fern genus Pteris.

Apomixis, a type of asexual reproduction characterized by the production of meiotic products without a reduction in chromosome number, has been observed in a variety of lineages across the tree of life. However, in no group is this reproductive pathway as prevalent as in ferns. Apomixis has been observed in approximately 10% of fern species examined, compared to less than 1% of flowering plant species. The fern genus Pteris has been reported to have an even higher incidence of apomixis (34–39%). However, these estimates were based on taxonomically and geographically limited samples. Here, using counts of spore-number-per-sporangium, we determined reproductive mode for over 100 additional species of Pteris and re-examined the prevalence of apomixis within the genus. Combining our survey with published counts, we found that among all Pteris species examined, only 21% were exclusively apomictic, with 71% exclusively sexual and 8% displaying both types of reproduction. These findings are considerably lower than previously published estimates. It is notable that all the specimens used in our study were collected during earlier expeditions, allowing us to easily broaden the geographical sampling of Pteris in this study, thus highlighting the continued importance of herbaria and other natural history collections in informing studies of ecology and evolution, even in the molecular age. Moving forward, we hope to further explore the relationship between species range and reproductive mode and to more fully assess the impact of apomixis on the distribution and diversity of Pteris.

1 - Johns Hopkins University , Baltimore , MD, 21218, USA
2 - Smithsonian Institution, Department of Botany, Washington , DC, 20013, USA
3 - University Of Minnesota Duluth, Biology, 1035 Kirby Drive, SSB 207, Duluth, MN, 55812, United States
4 - Duke University, Department Of Biology, Box 90338, Durham, NC, 27708, United States
5 - Smithsonian Institution, Department Of Botany, MRC 166 PO Box 37012, Washington, DC, 20013, United States

Keywords:
ferns
Apomixis
natural history collections
asexuality
reproductive mode.

Presentation Type: Oral Paper
Session: PTER1, Pteridology I
Location: San Pedro 1/Starr Pass
Date: Monday, July 29th, 2019
Time: 8:30 AM
Number: PTER1003
Abstract ID:457
Candidate for Awards:Edgar T. Wherry award