These dogs can detect a fungus. Can you?

Dogs are great at detecting things that are hard for humans to smell. But we don’t always know which chemicals are responsible for the scents that our four-legged friends pick up.

One group of researchers at Texas Tech University trained working dogs to identify the scent of powdery mildew, a fungus that infects grapevines and other plants. Now, another group is analyzing the volatile compounds emitted by infected leaves to figure out which molecules are responsible for the telltale smell.

Read an ACS press release about this research: Guardians of the vineyard canines and chemistry team up to combat powdery mildew.

“Evaluating chemical odor profiles of Vitis vinifera: Odor profiling for pathogen identification”
Presented at ACS Spring 2025 on March 23, 2025 by Nayelly Rangel
Principal investigator: Paola Prada-Tiedemann, Ph.D.

Video credits:
Written and produced by Anne Hylden
Edited by Mónica Pinzón
Narrated by Emily Schneider
Series produced by Vangie Koonce and Andrew Sobey
Executive produced by Matthew Radcliff
Chemistry lab videos from Nayelly Rangel

Working dog videos from Riannon Rowley (provided courtesy of the Texas Tech Graduate School),
Sarah Kane, Liza Rothkoff and Arieli Da Fonseca
Additional video: Shutterstock
3D molecule images: PubChem (CID 5281515, CID 11552)
Sound effects: Soundsnap
Music: “A Charming Promise” by Boris Skalsky on Triple Scoop Music

Transcript

These dogs know something analytical chemists are still trying to figure out. What does this plant disease smell like? Powdery mildew is a fungus that kills grapevines. Dogs can identify infected grape leaves by sniffing them, which can help vineyard owners stop the disease from spreading. But scientists still aren’t sure which chemical compounds the dogs are smelling.

So they extracted molecules from the air around healthy and infected grape leaves, then analyzed the compounds. They learned that infected leaves emit a larger concentration of aldehydes and terpenes than healthy leaves. They’re working to determine whether the smell changes as the disease progresses, and they’ll test whether the dogs respond to specific compounds in the mixture or the overall bouquet.

This work will shed scientific light on what goes on in these dogs’ noses. This research is being presented at ACS Spring 2025, a meeting of the American Chemical Society.

Good dog!