Student Poster Display
Systematics, Evolution, and Biodiversity
Student
Student Competition
Rachel C. Vargas (she/her/hers)
Ph.D. Student in Quantitative Biology
University of Texas
Arlington, Texas
Alison Ravenscraft (she/her/hers)
Assistant Professor
University of Texas
Arlington, Texas
The possibility that gut microbes might assist herbivorous insects with dietary detoxification has been often proposed, but rarely studied. As a first step towards estimating the extent of this phenomenon, we isolated gut microbes from various herbivorous insects including beetles, caterpillars, and grasshoppers and measured their ability to degrade plant defense chemicals. Bacterial isolates were cultured in media containing one of five toxins common in either the Brassicaceae (allyl cyanide, phenylethyl isothiocyanate, and sulforaphane) or the Solanaceae (chlorogenic acid and rutin) and we measured how much of each toxin each isolate degraded using high performance liquid chromatography and gas chromatography. We predicted that bacteria isolated from insects specialized on a given plant family would better degrade the plant’s associated toxins. Overall, we found that herbivorous insects’ gut bacteria degrade brassicaceous toxins more readily than solanaceous toxins. Our hypothesis was supported: bacteria isolated from brassica specialists were more likely to degrade brassicaceous toxins, and vice versa. Future work will evaluate the in vivo effects of these bacteria on hosts insects reared on toxic diets. Our findings serve to broaden our understanding of the function of gut microbes in their hosts and take a first step towards estimating the ecological and evolutionary importance of symbiont mediated detoxification in the plant-insect chemical arms race.