Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/20/2004
Publication Date: 8/15/2005
Citation: Brunet, J. 2005. Plant-pollinator interactions and pollen dispersal. In: Dafni, A., Kevan P., Husband, P. (eds), Enviroquest, Cambridge, Canada, p. 56-82.
Technical Abstract: Reproduction in plants is determined not only by the inherent features of their breeding systems, but also by their interactions with pollen vectors, upon which they rely for pollen dispersal and pollen receipt. These interactions can be particularly complex in animal-pollinated species because pollinator behavior can be influenced by floral morphology, plant density, floral display, and other biotic and abiotic factors. For example, pollinators preferentially visit plants with greater floral display and visit more flowers in succession on larger inflorescences, although the proportion of flowers visited and the number of visits per flower often declines or remains the same on larger plants. In turn, the foraging behavior of pollinators can influence the magnitude of geitonogamy (among flower selfing) and the amount of pollen available for outcrossing (pollen discounting). Through their influence on geitonogamy and autogamy (within flower selfing) pollinators can modulate gene flow and the balance between selfing and cross-fertilization. In this chapter, I describe some of the specific effects that pollinators can have on pollen dispersal and reproductive success and the techniques and experimental designs used to study these effects. In particular, I discuss how to measure pollen dispersal, plant reproductive success, and phenotypic selection on floral traits. Then, I introduce approaches to study the impact of daily floral display on pollinator visitation rates, self-pollination, and pollen discounting. Finally, I provide a framework for studying the consequences of pollinator directionality and dichogamy (temporal separation of male and female functions within a flower) on geitonogamy, pollen transfer, and sex allocation of different flowers.