Pollination Ecology, Self-incompatibility and Genetic Diversity in the Herbaceous Eastern North American Spring Ephemeral, Erythronium americanum

Despite having been studied for over 100 years, Erythronium americanum still has many aspects that remain relatively unknown or show conflicting results. To address this deficiency, multiple populations of various sizes were studied across a wide latitudinal range. Field observations were used to study pollinator abundance and activity and hand pollinations were performed to examine pollen limitation and self-incompatibility. Novel molecular markers were developed and used to quantify genetic diversity, clonal diversity, and population structure. Hand pollination treatments (natural, hand supplemented and bagged flowers) showed that smaller populations of E. americanum were more pollen limited and may be more susceptible to natural or anthropogenic factors affecting pollinators (p=0.0227). Based on self and outcross pollination treatments, smaller populations were more self-incompatible than larger populations (p=0.0011) and some populations were suffering from inbreeding depression (p < 0.0001). Pollen tube growth indicated that self-pollen could be more successful due to the mentor effect of outcross pollen (p < 0.0001). Genetic analysis of populations showed that populations of E. americanum that appeared larger and more dense actually had less clonal diversity. These results suggest that smaller populations of E. americanum are more reliant on sexual reproduction and that clonal recruitment increases as populations increase in size. Larger populations were dominated by fewer clones and were less genetically diverse than smaller populations. However, larger populations also displayed lower self-incompatibility, which could increase survivability of populations in cases of catastrophic bottleneck events. Implications from this research reach far beyond a common spring ephemeral and may be applicable to the many species which share some of the characteristics with E. americanum.

Name thesis:degree_name

PhD

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Arts and Sciences: Biological Sciences

Grantor dc:publisher

University of Cincinnati

Year dc:date

2012

Author dc:creator

• Stokes, Richard L.

Contributors dc:contributor

• Culley, Theresa

• Biology
• Pollination Ecology
• Genetic Variation
• Microsatellite
• Self-Incompatibility
• Erythronium americanum
• Clonal

Statement dc:rights

• unrestricted
• This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws.

Language dc:language

English

Repository record dc:identifier

http://rave.ohiolink.edu/etdc/view?acc_num=ucin1353089025

OAI identifier oai:identifier

oai:etd.ohiolink.edu:ucin1353089025