Denis Willett: Learning the language of underground organisms
Denis Willett, assistant professor of entomology, runs an unusual kind of school: His pupils spend most of their class time underground.
They learn via chemical cues and only retain information for 48 hours. But a crash course is all they need to succeed in the real world.
Called entomopathogenic nematodes, these millimeter-sized worms infect and kill the insects that eat the roots of important crops, such as corn, onions and turfgrass. In the nematode school, Willett teaches the worms how to find insect pests by following the chemical distress signals that plants release.
“By teaching the nematodes to respond to these cues, we can increase our efficacy and put them into new environments,” he says. “It’s an alternative to pesticides in many cases.”
Nematodes are just one type of underground organism that Willett and his team study in the Applied Chemical Ecology and Technology Lab at Cornell AgriTech, part of the College of Agriculture and Life Sciences. Their goal is to understand how plants, insects and microorganisms interact with their environments. With expertise that spans chemistry, computer science, entomology, engineering and plant physiology, Willett and his team develop applied solutions that benefit agriculture.
Willett, who joined AgriTech in 2018, specializes in applied insect chemical ecology. He uses robot-assisted technology to collect the smells that organisms produce, which allows him to essentially eavesdrop on the chemical “conversations” happening below ground and make decisions to support growers.
“Cornell in general, but also the AgriTech station, is a pretty remarkable place to do research,” he says. “The people are phenomenal, and the ideas and conversations really make it an exciting place to work.”
One of the other key organisms his lab studies is called phytophthora – a devastating pathogen that was responsible for the Irish potato famine of the 1840s. It has a mobile life stage, called a zoospore, that in some species swims in search of new plants to infect. This single-cell organism has no brain, yet it can sense chemical compounds and make choices about whether to move toward or away from them.
“It can travel really, really fast. We calculated that if it were a human, it could do the space of a couple of football fields in a second,” Willett says. “We’re really excited about deciphering how this single cell makes decisions and how it navigates the world.”
– Jana Wiegand
This article also appeared in the Cornell Chronicle.
Read the spring 2020 issue of Ezra magazine to learn about the other three faculty
