1st Place: Under your nose: How olfactory cues influence recognition and preference of fungal symbionts

Monday, November 14, 2022

9:36 AM – 9:48 AM PT

Location: Vancouver Convention Centre, Meeting Room 224

Presenting Author(s)

Alison H. Jennings (she/her/hers)

Undergraduate Research Assistant
The Ohio State University
Dublin, Ohio

Co-Author(s)

AG

Alissa R. Geisse

PhD student
The Ohio State University
Columbus, Ohio
OK

Olivia Kuethe

The Ohio State University
Columbus, Ohio
Rachelle M. Adams

Assistant Professor
The Ohio State University
Columbus, Ohio

For at least 55 million years, fungus-growing ants (tribe: Attini) have maintained an intimate mutualism with their co-evolved fungal cultivar. The farmer ants cultivate their gardens by providing it with resources, and in turn, the fungus serves as an obligate food source to raise young. Fungus-growing ant species are exclusive to their cultivar strain despite other fungi being readily available. We examine the precision of Cyphomyrmex costatus’ ability to differentiate between closely related fungi, including strains that are associated with another Cyphomyrmex species, C. muelleri. We hypothesize that if given the choice, Cyphomyrmex ants will show preference for fungal strains that are most genetically similar to their original garden. This ability to differentiate gardens is most likely driven by the ant’s ability to detect chemical differences between strains; however, the chemistry of these gardens remains unknown. We have been actively isolating cultivar from our laboratory colonies onto PDA-Cl agar plates. We performed DNA extractions on isolated cultivar and constructed a preliminary phylogeny including previously published DNA sequences. Furthermore, we used behavioral assays to test our hypothesis that Cyphomyrmex ants prefer gardens that are more closely related to their native cultivar when given a choice between two garden choices. These behavioral and genetic studies will inform future questions about the importance of certain chemical cues in ant decision-making, and if there is a genetic basis for chemical volatiles associated with the mutualistic fungi.