PARENT SESSION
Contributed Oral Session 85: Mutualism: Pollination
Wednesday, August 10, 8:00 AM - 11:30 AM, Meeting Room 520 C, Level 5, Palais des congrès de Montréal
Multiple pollinator visits to Mimulus ringens flowers increase mate number and seed set within fruits.
Mitchell, Randall*,1, Karron, Jeffrey2, Bell, John2, 3, 1 University of Akron, Akron, OH, USA2 University of Wisconsin-Milwaukee, Milwaukee, WI, USA3 Applied Ecological Services Inc, Brodhead, WI, USA
ABSTRACT- We investigated how the number and timing of pollinator visits to flowers affect the quantity and quality of offspring. To do this we recorded patterns of visitation, seed set, outcrossing rates, and paternity for individual flowers in an experimental array of monkeyflower, Mimulus ringens L. (Phrymaceae). A team of four observers recorded every probe to all 144 flowers in the array, documenting a wide range of visitation histories for individual flowers. Flowers received 0 to 8 total probes (mean = 2.7) during their one-day lifespans, and the interval separating sequential probes ranged from <1 to >100 minutes. Both the number and quality of seeds in these fruits varied as a function of visitation history. Flowers receiving three probes had 56.7% more seeds than flowers probed once. All fruits were multiply sired. Flowers receiving a single probe averaged 3.1 outcross sires per fruit, indicating that single probes deposit pollen from several plants. Multiple paternity was even greater for flowers receiving three or more probes (4.9 outcross sires per fruit), suggesting that sequential visits bring pollen from additional donors not represented in the initial probe. The time separating the first and second probe did not affect number of sires per fruit or seed number. Our results suggest that the great variability among flowers in their visitation histories strongly influences mating patterns and reproductive success
Key words: multiple paternity, paternity analysis, pollination and seed set, bumble bee (Bombus)