In the fight to rein in an invasive vine, University of Florida researchers have discovered going it alone isn’t always the best option. Sometimes, it takes teamwork to solve a problem that has long bugged Florida growers and land managers.
UF Institute of Food and Agricultural Sciences (UF/IFAS) discovered two similar beetles used on air potato vines don’t interfere with one another when used as biocontrol. Instead, they form a partnership for a potential green solution to control these damaging vines.
Air potato vines are damaging to crops and native plants alike, climbing high into the treetops and choking out sunlight, as well as blanketing the understory. The economic damage to the state of Florida caused by these vines includes ecological loss, agricultural loss, property damage and the cost of removal and management.
“It’s everywhere. It’s stubborn and was nearly impossible to stop,” said Jasleen Kaur, post-doctoral associate in the UF/IFAS Department of Entomology and Nematology. It’s also highly toxic, so it doesn’t have many natural enemies or pests.
Biocontrol for air potato vines has long been used to manage these invasive plants, but figuring out the right strategy has been tricky, said Phil Hahn, UF/IFAS assistant professor of entomology.
One beetle that eats the plants’ leaves, Lilioceris cheni, was introduced in Florida about a decade ago to combat the vines without herbicides, and it was somewhat effective, Hahn said. But stubborn populations of air potato vines persisted, so a second beetle, Lilioceris egena, that eats the tubers, known as “air potatoes,” was added in 2022 to clean up the job.
A recent study Hahn and Kaur published in Biological Control – in collaboration with the Florida Department of Agriculture and Consumer Services – showed that using both types of beetles together can help beat back the invasive plant better than one or the other by itself.
That’s notable because insects can often compete for resources, or literally fight one another, when put in close contact. But when these two types of beetles fed on the same air potato vines, they lived in harmony, and the air potato vines withered faster, Kaur said.
“They tag team to attack the vine from both ends,” she said.
Another layer to this study is how the plant responded to each type of beetle and whether its toxin had an effect on the insects.
For the leaf-eating beetle, the air potato vines put out more toxins like saponins in defense – but because of their evolutionary adaptations, the beetles thrived even better, leading to stronger suppression of the plant.
For the tuber-eating beetles, they don’t benefit from the toxin, possibly because the starchy air potatoes dilute it. Thus, each beetle has its own role, or niche, in the ecosystem that turns out to provide a potential control of this invasive plant. The next steps for research would be field trials to test the method outside of the lab.
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ABOUT UF/IFAS
The mission of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) is to develop knowledge relevant to agricultural, human and natural resources and to make that knowledge available to sustain and enhance the quality of human life. With more than a dozen research facilities, 67 county Extension offices, and award-winning students and faculty in the UF College of Agricultural and Life Sciences, UF/IFAS brings science-based solutions to the state’s agricultural and natural resources industries, and all Florida residents.
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