Document: MAR-3-44-3

Pollination biology of saw palmetto (Serenoa repens: Palmae) in southwestern Florida.

CARRINGTON, M.E.*, T.D.GOTTFRIED and J.J.MULLAHEY

Southwest Florida Research and Education Center, Immokalee, FL, 34142, USA ¹

Abstract:
We characterized timing and mechanisms of flowering and pollination for saw palmetto (Serenoa repens), a bushy palm species native to the southeastern United States. We designed the study to accomplish three primary objectives: 1) quantify duration of anthesis, 2) characterize timing of pollination, and 3) determine if insect pollinators are required for seed set. We documented timing of anthesis and pollination by observing opening of marked flowers during 12-hour periods, and by quantifying anther dehiscence, presence of nectar and stigma receptivity for flowers collected at increasing times after opening. We characterized the breeding system of saw palmetto by quantifying seed set of experimentally manipulated flowers. In addition, we identified potential insect pollinators by observing visitation to flowers, and quantifying pollen loads on collected insect visitors. We found that anthesis lasted approximately 4 days. Flowers were weakly protandrous, with anther dehiscence occurring primarily during the first day of anthesis, and stigma receptivity primarily during the second through fourth day. Probability of pollination was highest on the second day of anthesis, when stigmas were receptive and presence of nectar in flowers was reliable. Saw palmetto flowers were facultatively xenogamous, with insects needed for transfer of pollen. Of 34 species of insects that we observed visiting the flowers, the European honeybee (Apis mellifera) and three native bee species appeared to be primary pollinators.

Keywords: palms, pollination biology, saw palmetto, _Serenoa_

This abstract is being presented at: 9:00 AM in session:
Oral Session #6: Pollination Ecology.