Pollination of Rubus arcticus L. in Alberta: microclimate effects on pollinator availability and the role of pollen limitation on fruit set

• Main Author: Burns, Cole
• Other Authors: Vamosi, Jana C., Cartar, Ralph Victor, Longair, Robert W.
• Format: Master Thesis
• Language: English
• Published: Graduate Studies 2018
• Subjects: Pollen Limitation; Microclimate; Pollen Quantity; Pollen Quality; Fruit set; Pollen Supplementation; Pollinator Diversity; Foraging Duration; Visitation; Rubus arcticus; Arctic Raspberry; Hemispherical Photography; Time-lapse Photography; Pollinator Surveys; Biology; Botany; Ecology; Plant Physiology; Arctic
• Online Access: http://hdl.handle.net/1880/106687; https://doi.org/10.11575/PRISM/31954

Rubus arcticus Linnaeus is a widespread plant species that likely experiences changes in pollinator visitation and fruit production with microclimate. A pollen supplementation experiment with open controls, pure-selfed and outcross supplemented treatments was used to determine if R. arcticus fruit production is limited in the quantity of pollen deposited. This experiment was then complemented by a pollen tube analysis to determine the importance of pollen quality. To determine the effects of microclimate on R. arcticus pollinator availability and foraging behavior, pollinator surveys were conducted using time-lapse photography which was accompanied by micrometeorological monitoring with measurements from humidity/temperature loggers, an anemometer for wind speed, and hemispherical photography for solar irradiance. The results provide evidence that fruit production in R. arcticus can be extremely low in regions that are at the southern parts of its range, but this low fruit production does not necessarily reflect pollen limitation. The dominant pollinators of the study population were syrphid flies, which exhibited visitation frequencies that were influenced by temperature and humidity