| Title: | Floral Scent Composition and Fine-Scale Timing in Two Moth-Pollinated Hawaiian Schiedea (Caryophyllaceae) |
| Author(s): | Powers JM; Seco R; Faiola CL; Sakai AK; Weller SG; Campbell DR; Guenther A; |
| Address: | "Department of Ecology and Evolutionary Biology, University of California, Irvine, Irvine, CA, United States. Terrestrial Ecology Section, Department of Biology, University of Copenhagen, Copenhagen, Denmark. Center for Permafrost (CENPERM), Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark. Department of Earth System Science, University of California, Irvine, Irvine, CA, United States" |
| ISSN/ISBN: | 1664-462X (Print) 1664-462X (Electronic) 1664-462X (Linking) |
| Abstract: | "Floral scent often intensifies during periods of pollinator activity, but the degree of this synchrony may vary among scent compounds depending on their function. Related plant species with the same pollinator may exhibit similar timing and composition of floral scent. We compared timing and composition of floral volatiles for two endemic Hawaiian plant species, Schiedea kaalae and S. hookeri (Caryophyllaceae). For S. kaalae, we also compared the daily timing of emission of floral volatiles to evening visits of their shared pollinator, an endemic Hawaiian moth (Pseudoschrankia brevipalpis; Erebidae). The identity and amount of floral volatiles were measured in the greenhouse during day and evening periods with dynamic headspace sampling and GC-MS (gas chromatography - mass spectrometry). The timing of emissions (daily rise, peak, and fall) was measured by sampling continuously for multiple days in a growth chamber with PTR-MS (proton transfer reaction mass spectrometry). Nearly all volatiles detected underwent strong daily cycles in emission. Timings of floral volatile emissions were similar for S. kaalae and S. hookeri, as expected for two species sharing the same pollinator. For S. kaalae, many volatiles known to attract moths, including several linalool oxides and 2-phenylacetaldehyde, peaked within 2 h of the peak visitation time of the moth which pollinates both species. Floral volatiles of both species that peaked in the evening were also emitted several hours before and after the brief window of pollinator activity. Few volatiles followed a daytime emission pattern, consistent with increased apparency to visitors only at night. The scent blends of the two species differed in their major components and were most distinct from each other in the evening. The qualitative difference in evening scent composition between the two Schiedea species may reflect their distinct evolutionary history and may indicate that the moth species uses several different floral cues to locate rewards" |
| Keywords: | Pseudoschrankia Schiedea hookeri Schiedea kaalae floral volatiles gas chromatography - mass spectrometry (GC-MS) island flora moth pollination proton transfer reaction - mass spectrometry (PTR-MS); |
| Notes: | "PubMed-not-MEDLINEPowers, John M Seco, Roger Faiola, Celia L Sakai, Ann K Weller, Stephen G Campbell, Diane R Guenther, Alex eng Switzerland 2020/08/15 Front Plant Sci. 2020 Jul 21; 11:1116. doi: 10.3389/fpls.2020.01116. eCollection 2020" |
