Microbes keep the bees buzzing

Authors: DHARAMPAL, PRARTHANA - University Of Wisconsin; DIAZ-GARCIA, LUIS - University Of Wisconsin; CARLSON, CAITLIN - University Of Wisconsin; CURRIE, CAMERON - University Of Wisconsin; Zalapa, Juan; HITTINGER, CHRISTOPHER - University Of Wisconsin; Steffan, Shawn

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/18/2018
Publication Date: 3/21/2018
Citation: Dharampal, P.S., Diaz-Garcia, L., Carlson, C., Currie, C., Zalapa, J.E., Hittinger, C.T., Steffan, S.A. 2018. Microbes keep the bees buzzing. 2018 Annual Meeting, North-Central Branch of the Entomological Society of America. Madison, Wisconsin. March 18-21, 2018.

Interpretive Summary:

Technical Abstract: Microbes likely represent a major dietary resource for larval bees. Despite their importance in sustaining bee health, empirical evidence linking pollen-borne microbes to larval health is currently lacking. Here, we examined the effects of microbe-deficient diets on the fitness of larval mason bees. In a series of diet manipulations, microbe-rich maternally-collected pollen provisions were replaced with increasing fractions of sterilized microbe-deficient pollen, prior to larval consumption. We found that larvae feeding on increasingly sterile diets had significant adverse effects on larval growth rates, biomass, and survivorship. Trophic biomarker analysis revealed that larval bees derived a substantial amount of nutrition from microbial prey. When deprived of microbes, the predominantly pollen-eating larvae showed marked decline in health. We conclude that pollen-associated microbes are central to bee health, not only as nutritional mutualists, but also as a major dietary component. In an era of global bee decline, the conservation of such vital bee-microbe symbioses represents an important facet in pollinator protection strategies.