Abstract Detail

Ecological Section

Yadav-Pauletti, Sunita [1], Culley, Theresa [1].

Variation in floral characters among sexes of Schiedea globosa (Caryophyllaceae) in natural populations.

The evolution of breeding systems has been the subject of much scientific inquiry in terms of pollination and genetics, but there is still much to learn about how these systems are potentially shaped by their geography. Schiedea globosa, a subdioecious species, from the Hawaiian Islands has been examined previously to understand the ecological correlates of breeding systems. In this study, we evaluated whether there are differences in floral traits among sexes (male, female, and hermaphrodites) and how these might be influenced by geographic location or abiotic factors in the environment. We surveyed four populations of S. globosa on coastal areas of northwest Maui and southeast Oahu during the 2012 flowering season. There were significant differences among sexes for total flower number, peduncle length, and lateral branch length but not for inflorescence length. Hermaphrodites showed relatively lower flower numbers compared to unisexual individuals. Peduncle length in females was significantly higher than for hermaphroditic individuals and lateral branch length was significantly higher for females in comparison to males. Regression analysis using geographic location, elevation, and soil depth were significant in predicting total flower number in male plants with greater flower number at higher elevations. These floral differences among sexes are consistent with differential resource allocation which in turn could influence breeding system evolution within the species. This research provides some support for the hypothesis that habitat conditions in S. globosa are associated with the maintenance of subdioecy within the species.

Broader Impacts:

1 - University Of Cincinnati, Department Of Biological Sciences, 614 Rieveschl Hall, Cincinnati, OH, 45221-0006, USA

Keywords:
subdioecy
floral structure
Schiedea
geography.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Battelle South/Convention Center
Date: Monday, July 9th, 2012
Time: 5:45 PM
Number: PEC009
Abstract ID:983