New study shows increased antioxidant consumption slows pesticide resistance in fruit flies
MSU researcher: Potential promise at mitigating the evolution of pesticide resistance
EAST LANSING, Mich. – The long-term human health benefits of antioxidants are well documented, but could these substances also prove beneficial to insects?
MSU Foundation Professor Barry Pittendrigh is studying the role dietary antioxidant consumption through plants has on mitigating the evolution of pesticide resistance in insects. His study, published recently in Pesticide Biochemistry and Physiology, determined that increasing the dietary intake of vitamin C significantly decreased DDT resistance in Drosophila, or fruit flies.
He said this is a first step to determine if increasing antioxidant levels in plants could slow the evolution of pesticide resistance in insects.
“In the long term, if this is confirmed in other systems, we can see the potential for breeding plant varieties that have higher antioxidant levels to potentially slow the pace of evolution resistance to pesticide,” said Pittendrigh, a professor and researcher in the MSU Department of Entomology.
“This is something that we’ve been mulling around for quite some time in the laboratory, so I’m very happy to have this work see the light of day. We have a lot of other questions around the issue of how we can impact the pace of the evolution of resistance.”
Pesticide resistance is a threat to the sustainability of crop and livestock production, where lack of control of resistant insect populations causes annual losses valued at several billion dollars across the U.S. agricultural sector, according to the paper.
Pittendrigh based the hypothesis on anecdotal evidence that species of insects that consume large amounts of plant material with high levels of antioxidants, like blueberries, tend to have fewer cases of resistance.
“This is a model system as fruit flies are a genetically tractable system and DDT is no longer a commercially used compound,” he said. “However, both of these tools allow for tightly controlled experimental conditions in the lab that allowed us to test our working hypothesis.
“Our hypothesis was that over the long term, dietary antioxidants would slow the pace or the evolution of resistance, and that’s what we observed.”
Insects that received antioxidants in the study did not evolve resistance at the same pace that occurred in the absence of antioxidants, he said.
The group tested four replicate populations of fruit flies with a control group: one group received antioxidants only (Vitamin C); one group received antioxidants plus pesticide; and one that received pesticide only. Those insects that received the antioxidant plus pesticides did not evolve resistance as rapidly as the pesticide only treatment.
“It’s important to state that this is a model system to test this hypothesis,” he said. “Our inference space is one type of antioxidant with one type of pesticide in one population of a single insect species under very specific conditions.
“However, it does open up the possibility that this phenomenon may occur across other pesticides and other classes of antioxidants – a hypothesis that remains to be tested.”
Pittendrigh partnered on the study with researchers from China, South Korea, Nigeria, the University of Kentucky, Iowa State University, the University of Illinois at Urbana-Champaign and the University of Massachusetts-Amherst.