Abstract Detail



Sexual selection in flowering plants: traits, processes, and estimation

Chang, Shumei [1].

Is pollen size an “honest” male trait during pollen competition?

Pollen size has been shown to positively correlate with siring success during pollen competition in several species.  Pollen size variation has been found both within and between populations of the common morning glory, Ipomoea purpurea.  Previous work showed that there is a genetic basis for such variation and pollen size has responded to artificial selection in the greenhouse. These results indicate that pollen size is a heritable trait that reflects gametophytic competitiveness of a plant, and hence, can be considered a male trait important for post-pollination competition. However, genetic differences were the focus of these earlier studies and ecological conditions, which are known to affect pollen size, were not studied.  Here we investigate whether pollen size is a reliable male trait by exposing plants that diverged genetically in their pollen size to different ecological conditions, particularly soil nutrient. We evaluated the effect of interaction between genetic and ecology (GxE interaction) on the property of pollen by measuring the following pollen traits: size, number per flower, nutrient content, and pollen tube germination rate. In addition, we also tested the relative siring success of pollen competitors that vary in their genetics and/or environments.  Using these results, we discuss whether pollen size can serve as an “honest signal” for the quality of the pollen donor plants, as well as the implication on how sexual selection may operate during post-pollination stage. 


1 - University Of Georgia, Plant Biology Department, 2502 Plant Sciences Bldg, Athens, GA, 30602, United States

Keywords:
Sexual selection
Pollen competition
Ipomoea purpurea
pollen size.

Presentation Type: Colloquium Presentations
Number: 0003
Abstract ID:485
Candidate for Awards:None


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