Air Potato Leaf Beetles Eat Only Air Potatoes
By Les Harrison
Wakulla County Extension Director
Sometimes surprises can puzzle and perplex, and yet be pleasant. Finding a twenty dollar bill, for example, in a parking lot would certainly be a positive experience.
The occurrence would likely be tinged with pity for the person who lost it, though. Even if they were totally careless with their financial resources the discovery would make one wonder what had caused their misfortune.
Possibly it was some distraction or disruption to the daily routine which caused a momentary lapse of judgment. The event would be noteworthy even if the subject was small and easily overlooked by a majority of Wakulla County’s residents.
Such was the case when a small, but brightly colored beetle appeared in the UF/IFAS Wakulla County Master Gardener Demonstration Garden. Specifically, it was found in the sorghum which was planted as a trap crop to attract destructive insects.
The beetle, less than half an inch long, has a candy apple red body which stood out against the green leaves and the more muted earth tones of other bugs inhabiting the plants. The striking bright glossy red coating would be the envy of any sports car owner or fire truck driver.
After some checking, the beetle was identified as the Air Potato Leaf Beetle (Liliocetis cheni), a native of east Asia. Unlike some recent arrivals to the U.S., this insect was deliberately released in 2012 for the biological control of air potatoes.
The air potato (Dioscorea bulbifera) is an herbaceous perennial vine which is easily capable of exceeding 60 feet in length. It quickly will climb over any plant, tree or structure which in unfortunate enough to be in the vicinity of its germination.
Air potatoes came to Florida in 1905 from China and quickly escaped into the wild. By the 1980’s it was a serious pest species in south and central Florida, but has gradually become established in the panhandle, too.
Control of the air potato has been difficult. Repeated herbicide treatments are required to kill a thicket with multiple plants.
Also, it produces copious quantities of potato like tubers suspended from its vines. Unless collected and destroyed, most of the easily camouflaged potatoes will germinate and intensify the problem.
After years of testing, approval was finally given to release Air Potato Leaf Beetles (APLB) to begin their foraging campaign against this exotic invasive plant species. The larvae and adults of this species consume leaf tissue and occasionally feed on the tubers.
Unlike the Kudzu Bug which is also established in Wakulla County, the APLB eats only from the air potato plant. Kudzu Bugs do eat their namesake vine, but a number of other plants including a wide selection of valuable legumes.
Kudzu Bugs were accidently introduce in north Georgia in 2009 and have spread across the south in the ensuing years. They were first identified in Wakulla County in 2013.
When the APLB’s finish off an air potato thicket, they go in search of nourishment from a new infestation. Their stop over at the UF/IFAS Wakulla Extension Office was long enough to determine there was nothing for them to eat there, and they departed.
It was a pleasant surprise to know they are working the areas, but it is sad to think there is plenty more for them to eat.
Read more about the Air Potato here.