Abstract Detail

Pollination Biology

Lin, Shang-Yao (Peter) [1], Nol, Erica [1], Dorken, Marcel [2].

Spatial dynamics of pollination in dioecious Shepherdia canadensis (Elaeagnaceae) .

Shepherdia canadensis is a dioecious shrub common to forested ecosystems throughout Canada. This study examines patterns of sexual dimorphism and the pollination biology of S. canadensis in Ivvavik National Park, Yukon, Canada at the northern limit of its distribution. I found that females were larger than the males, but that males occurred at higher frequencies and produced more flowers than females at most sites. Shepherdia canadensis flowers were primarily visited by ants and flower flies (Syrphidae), however, a manipulative experiment revealed that only flying insect visitors contribute to the reproductive success of the females. To examine the relationships between male densities across spatial scales against two measures of reproductive success (stigmatic pollen load and fruit set), all flowering individuals were mapped in two study sites. I detected a significant positive association between fruit set and male densities at spatial scales of 6 m or less, and this association disappeared with increasing distances between females and males. This study clarifies the roles of crawling versus flying insects in the pollination of S. canadensis and reveals the spatial scale over which the majority of pollen is transferred and successfully fertilized females within populations.

Broader Impacts:

1 - Trent University, Biology Department, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, CANADA
2 - Trent University, Biology, 1600 West Bank Drive, Peterborough, ON, K9J 7B8, Canada

Keywords:
dioecy
pollination
Arctic
sexual dimorphism
sex ratio.

Presentation Type: Oral Paper:Papers for Topics
Session: 45
Location: Melrose/Riverside Hilton
Date: Wednesday, July 31st, 2013
Time: 1:30 PM
Number: 45001
Abstract ID:304
Candidate for Awards:None