DISSERTATION RESEARCH: Microbial mediation of polliator performance

Dartmouth College, Hanover NH

Investigators

Abstract

Floral nectar is a fundamental resource important for mediating interactions between plants and pollinators. As the primary energy source for most pollinating animals, nectar not only fuels their flight, but also can be an important determinant of pollinator reproduction. Considering its nutritional value, it should be of no surprise that microorganisms such as yeasts often colonize nectar. Yeasts may exploit nectar at the potential expense of plants and pollinators. For example, yeast metabolic activity has the potential to modify the taste and nutritional value of nectar, which may affect pollinator attraction, behavior, and subsequent plant reproduction. Given that yeasts may affect the nutritional value of nectar, they may also have effects on the performance and reproduction of pollinators. This research project will experimentally test the degree to which yeasts in floral nectar affect bumble bee pollinator behavior and reproduction, and also examine the mechanisms involved utilizing laboratory experiments. Results from this research will highlight a previously unstudied factor in plant-pollinator interactions, yeast, whose growth in nectar may mediate the mutual benefits received by plants and pollinators from one another. Bumble bee pollination is a critical ecosystem service that facilitates both native plant reproduction and agricultural crop yield, as approximately 90% of flowering plants rely on insects or other animals for pollination. This research project will identify interactions and mechanisms that may limit bumble bee development and reproduction, insight that may be important for conservation and commercial enterprises seeking to preserve or develop species for pollination services. Moreover, by conducting this research with a commercially important pollinator for agricultural services, our results may have application to mechanisms that affect its success. Understanding mechanisms through which microbial organisms affect plant-animal systems will fill a void in our knowledge of the ecology of microbial organisms and the role they play in ecological communities.