Wednesday, 20 November 2002

This presentation is part of : Display Presentations, Subsection Cd. Behavior and Ecology

Aggregation factors of the German cockroach are produced by gut microbial symbionts

Godfrey Nalyanya1, Ludek Zurek1, Aijun Zhang2, Wendell L. Roelofs3, and Coby Schal1. (1) North Carolina State University, Department of Entomology, Gardner Hall 3109, Raleigh, NC, (2) USDA ARS Plant Science Institute, Chemicals Affecting Insect Behavior Laboratory, 10300 Baltimore Avenue, Beltsville, MD, (3) Cornell University, Department of Entomology, Barton Lab, New York State Agricultural Experiment Station, Geneva, NY

Based on previous findings that aggregation behavior in the German cockroach, Blattella germanica, is mediated by a mix of volatile carboxylic acids [Scherkenbeck J. et al. 1999. J. Chem. Ecol. 25:1105-1119], we hypothesized that symbiotic microbes might be involved. Aggregation assays in dishes and olfactometer assays in Y-tubes revealed significant differences in the attractiveness of fecal extracts of German cockroaches reared under sterile or non-sterile conditions. Eleven species of bacteria were aerobically cultured and isolated on broad-spectrum and selective artificial media from feces of non-sterile cockroaches and identified by phenotype and sequencing of 16S rDNA. Sterile first instars cockroaches inoculated orally with individual or mixtures of bacterial isolates produced feces that was significantly more attractive to conspecifics than the feces of sterile cockroaches. These results show that gut microbes are involved in the production of B. germanica aggregation attractants and arrestants. Analysis of carboxylic acids from feces extracts by GC-MS revealed significant differences between sterile and non-sterile feces.

Species 1: Blattaria Blattellidae Blattella germanica (German cockroach)
Keywords: aggregation pheromone, fatty acid

Back to Display Presentations, Subsection Cd. Behavior and Ecology
Back to Posters
Back to The 2002 ESA Annual Meeting and Exhibition