Abstract Detail

Ecological Section

Bell, Timothy [1], Bowles, Marlin [2], Zettler, Lawrence [3], Poulter, Sarah [4].

Crossing effects on seed viability, germination and protocorm growth of the federal threatened Eastern Prairie Fringed Orchid (Platanthera leucophaea).

Eastern Prairie Fringed Orchid (Platanthera leucophaea) is a federally threatened prairie perennial in which seed germination is promoted by symbiosis with the mycorrhizal fungus Ceratorhiza. Use of multiple versus single seed sources for restoration is of concern due to the potential for outcrossing depression. To address this issue, we compared seed viability, germination and protocorm growth for progeny from flowers that were either selfed (S), received pollen from another plant from the same population (outcrossed within, OW) or received pollen from another plant from a different population (outcrossed between, OB). In 2000, plants from three populations separated by as much as 158 km were included in the experimental pollination. In 2002 and 2004, the experiment was repeated using populations separated by 309 km. In both 2000 and 2002, seed viability was significantly lower for S progeny but there was no significant difference between OW and OB progeny. Germination was significantly lower for S but did not differ between OW and OB but protocorm growth was significantly greater for OB at the most advanced of five growth stages. Viability andd germination results are not yet available for the 2004 crosses. Although the effects of outbreeding depression may not appear for several generations, our short-term results indicate that starting a new population of Eastern Prairie Fringed Orchid by introducing seeds from multiple populations should not be detrimental.

1 - Chicago State University, Biological Sciences, 9501 South King Drive, Chicago, Illinois, 60628, USA
2 - The Morton Arboretum, 4100 Illinois Route 53, Lisle, Illinois, 60532, USA
3 - Illinois College, Biology, 1101 West College Ave., Jacksonville, Illinois, 62650, USA
4 - Southern Illinois Univ. - Edwardsville, Environmental Science, Edwardsville, Illinois, 62026, USA

Keywords:
outcrossing depression
threatened
germination
Platanthera leucophaea
orchid.

Presentation Type: Oral Paper
Session: 9-3
Location: Salon A - Gov Ballroom/Hilton
Date: Monday, August 15th, 2005
Time: 10:45 AM
Abstract ID:136