“Insects that eat crop plants cause, globally, billions of dollars worth of economic losses and create massive food instability,” said Berenbaum, professor and head of the Department of Entomology. “If food stability and sustainability are desirable economic goals then it’s really important to understand the basic components that underlie interactions between plants and insects.”
By understanding the basic principles by which a plant-feeding insect finds host plants, overcomes host plant defenses, and ultimately goes about its life, researchers will have newfound insight into managing many crop pests.
“How insects eat plants can be addressed at the molecular level by examining the genes that encode the enzymes that metabolize toxins all the way up to the landscape level where we have examined how plant-insect interactions have helped shape community composition,” she said.
As an ecologist by training, Berenbaum admires these pests.
“They are amazing,” she said. “It’s not easy for an insect to eat hundreds of different crop plants. It’s a real challenge.”
While most herbivorous insects can only consume a narrow range of host plants, the naval orange worm has managed to colonize just about every nut tree in California. It’s a major pest for almonds, walnuts, pistachios, figs, pomegranates, citrus, and other plants.
“How does this insect manage to process the tremendous diversity of phytochemicals in these unrelated plant families?” Berenbaum asks. “How can it overcome these chemical challenges in a relatively short amount of time, as pistachios were not grown in California until the 1970s? Why did it leave its native leguminous hosts to prey upon this unusual and phytochemically-challenging tree?”
It’s not just a matter of how many plants a bug eats. Berenbaum is equally impressed with the type of plant an insect will consume.
Take the parsnip webworm for example.
“Here is an insect that is native to Europe that feeds on just a handful of plants that are all closely related,” Berenbaum said. “It feeds on the plant parts that are richest in a group of chemicals that are incredibly toxic to just about every other life form.”
Parsnip webworms consume about 10 percent of their body weight in these deadly toxins, not only in Europe but also in other corners of the world where parsnips are grown. For Berenbaum, these insects raise some important, fundamental questions.
“How do you become so good at utilizing this one particular crop?” she said. “How do you find it? How do you get there? How do you deal with new, entirely different ecological communities?”
Berenbaum has been trying to answer some of these questions about parsnip webworms since her doctoral thesis. She earned her doctorate in ecology and evolutionary biology from Cornell University and before that graduated summa cum laude from Yale University with a bachelor’s degree in biology.
In 1980, two weeks after she finished her thesis, she began working at the University of Illinois. She became a professor in 1990 and began serving as the head of the Department of Entomology in 1992. Today she is also a member of the Genomic Ecology of Global Change research theme at the IGB.
Among many awards and honors, Berenbaum has received the Presidential Young Investigators’ Award and the Tyler Award for Environmental Achievement, and has been named a University Scholar, Elected Fellow by American Association for the Advancement of Science, and Elected Member of the National Academy of Sciences.
Recently, she was nominated by Chancellor Phyllis Wise to join the National Science Foundation’s Advisory Committee for the Biology Directorate.
This article originally appeared in the February 2014 Carl R. Woese Institute for Genomic Biology newsletter.