Sweetpotato weevils are the most feared predator of sweet potato crop known to man; researchers are working toward better methods for eliminating the pest.
The insects, also called Cylas formicarius, are especially resistant to extermination because the larvae live in "vines or tubers," and the adults only come out at night, an Entomological Society of America news release reported.
The pests are believed to have entered the U.S. through Cuba during the 1870s. They can now be found "throughout the coastal plain of the Southeast from North Carolina to Texas. It also is found in Hawaii and Puerto Rico, and widely around the world in tropical regions," the University of Florida reported.
Extermination methods such as chemical control have failed in the past. Mass trappings using synthetic pheromones has helped to reduce male sweetpotato weevil populations, but exterminators and farmers have not seen a significant decrease in crop damage, the Entomological Society of America news release reported.
New research suggests giving traps specific colors could effectively reduce populations of the sweetpotato weevil.
Dr. Gadi V.P. Reddy has been on a years-long mission to solve the sweetpotato weevil problem without using toxic chemicals or pesticides.
The researcher recently paired up with Nirupa Gadi of the University of Guam in order to get closer to a solution. The team discovered that traps that were painted green had a higher rate of catching the sweetpotato weevil indoors than traps of other colors. Outdoors red traps were found to be the most effective.
"Sweetpotato weevils responded to pheromone baited traps of different colors differently in the field and indoors," Doctor Gadi V.P. Reddy, said. "In the field, sweetpotato weevils preferred red, and particularly light red, over the other colors, but indoors, green traps were favored. We have no explanation for the difference. Further studies focusing on why insect behavior changes from outdoors to indoors will be required to find out."
The new research was published in the journal Annals of the Entomological Society of America.
