Bumblebees may be small, measuring only about an inch long, but they play an enormous role in global agriculture. About one third of the world’s food production relies on pollinators such as bees. At the same time, these vital insects face growing pressure from pesticides and other environmental threats.
Modern pesticides have helped farmers protect crops and increase yields, but some can also damage the pollinators that make many harvests possible. One such chemical is sulfoxaflor, a next generation pesticide introduced in 2013 to eliminate sap feeding insects such as aphids on crops including soybeans and corn. While sulfoxaflor is effective against pests, it is also known to be toxic to bees. Scientists are now uncovering how even low levels of exposure may affect bee reproduction at the molecular level.
Common Pesticide Alters Bee Gene Activity
Researchers at the Georgia Institute of Technology found evidence that sulfoxaflor changes both gene activity and reproductive function in bumblebees. In the U.S. Department of Agriculture funded study, worker bumblebees were exposed to low doses of the pesticide before researchers examined changes in their gene expression.
The largest changes appeared in ovarian tissue, suggesting that the pesticide may interfere with reproductive processes. According to the researchers, these genetic changes could reduce the number of offspring produced and, over time, contribute to declining bee populations.
To investigate these effects, the team flash froze bee tissues and analyzed their RNA to measure how gene activity changed after pesticide exposure. They also used computational models to identify the biological systems most affected by the chemical.
“What makes this study exciting is that it connects molecular changes in gene expression to real-world consequences for individual bees and their colonies,” said Michael Goodisman, a professor in the School of Biological Sciences. “That type of connection is rare and gives us a much clearer picture of how pesticides affect bees.”
Balancing Pest Control and Pollinator Protection
The findings underscore an ongoing challenge for modern agriculture: protecting crops from destructive pests without harming the beneficial insects that support food production.
“We need pesticides to control crop pests, but they can also harm essential non-target insects like bumblebees,” said Sarah Orr, who led the research as a postdoctoral fellow at Georgia Tech and now works as an assistant professor at the University of Tampa. “As a scientist, my goal is to identify practical solutions that support pest management while also protecting beneficial insects and the food systems that depend on them.”
Orr emphasized that maintaining healthy bee populations is essential for successful pollination.
“We need many bees for successful pollination,” Orr said. “If they’re not producing enough offspring, pollination will decline.”
Bumblebees Face Multiple Threats
Pesticides are only one of several challenges affecting bumblebees. Rising temperatures and increasingly frequent heatwaves are adding even more stress to pollinator populations.
By gaining a better understanding of how chemicals such as sulfoxaflor influence bee biology, researchers hope to develop farming practices that protect crops while also safeguarding the pollinators that many food systems depend on.