Location: Vegetable Crops Research Unit
Title: The impact of distinct insect pollinators on the movement of genes via pollen Authors
Submitted to: Symposium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2007
Publication Date: June 24, 2007
Citation: Brunet, J., Holmquist, K.G. 2007. The impact of distinct insect pollinators on the movement of genes via pollen [abstract]. 9th International Pollination Symposium on Plant-Pollinator Relationships-Diversity in Action, June 24-28, Ames, Iowa. pp. 56-57. Technical Abstract: Differences in the foraging behavior and grooming patterns of pollinators can influence the patterns of gene dispersal and the resulting genetic structure of plant populations. Bumblebees groom and are thought to visit nearest neighbor plants, behaviors which are both expected to generate more localized patterns of pollen dispersal and decrease effective neighborhood sizes relative to hawkmoths that do not groom and are thought to travel longer distances between plants. In addition, differences between pollinators in how genes are moved via male and female functions can affect the evolution of floral form and function. For example, if each pollinator specializes on a sexual function, this may create disruptive selection on floral morphology. In this study we compare the impact of bumble bees and hawkmoths on outcrossing rate and number of outcrossed seeds (female function), progeny genetic diversity, number of outcrossed seeds sired by a male (male function) and overall gene movement within and between patches in the rocky mountain columbine, Aquilegia coerulea. We contrasted outcrossing rate, seed set and number of outcrossed seeds per plant between pollinator treatments using ANOVA to examine the impact of pollinator type on female function. The impact of hawkmoths and bumble bees on male function was determined by comparing the number of outcrossed seeds sired by a male between pollination treatments. Outcrossing rates and pollen and ovule frequencies were jointly estimated using the Newton-Raphson iteration and the most likely parent method in the maximum likelihood MLTR program developed by Kermit Ritland. We provided the genotypes of mothers, associated progeny arrays and potential sires to the program PATRI for paternity analyses. Although their impact on genetic diversity and the genetic structure of the population was more similar than we had anticipated, the two major pollinators could create disruptive selection on floral traits in the population.