ARS | Publication request: Microbial Populations and Hypothesized Function within the Guts of Two Ground Beetles

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 16, 2007
Publication Date: May 23, 2007
Citation: Lehman, R.M., Lundgren, J.G., Chee Sanford, J.C. 2007. Microbial Populations and Hypothesized Function within the Guts of Two Ground Beetles. Meeting Abstract. 107th General Meeting of the American Society for Microbiology, Toronto, Ontario, Canada, May 21-25, 2007.

Technical Abstract: Bacteria colonizing the intestinal tract of beneficial ground beetles may contribute to the beetles’ fitness and ability to control plant and insect pests. Using tRFLP analysis (16S rRNA gene) of bacteria populations in the guts of ground beetles, we have found that individual beetles from the same beetle species (Harpalus pensylvanicus) harbor relatively simple and reproducible bacterial communities. Sequence analyses of the same gene identified six bacterial populations common to these beetles. In another ground beetle, Poecilus chalcites, we have found greater variation in the resident bacterial populations among individual beetles. When P. chalcites, a strict predator, is reared on cricket eggs, antibiotic treatment reduces the diversity of the gut bacterial populations, but does not affect feeding. When H. pensylvanicus, an omnivore, is reared on cricket eggs, antibiotic treatment also does not affect feeding. However, H. pensylvanicus reared on weed seeds and receiving antibiotic treatment exhibited reduced feeding. These findings suggest a nutritional role for the gut bacteria that may be mediated by diet or trophic position.