New Strain of Pesticide-Resistant Whiteflies Threatens to Destroy Palm Beach County Crops
Amada44 via Wikimedia Commons
The whitefly is back. Though it looks like the sort of adorable insect that would star in a Dreamworks film, the humble whitefly is actually a god-awful invasive species that will stop at nothing to decimate crops. The bug can carry more than 111 different plant-killing viruses — a wave of these little guys across the South in 1991 wiped out more than $500 million worth of crops.
"Vegetables were dying," says Dr. Lance Osborne, a University of Florida entomologist who has been studying whiteflies for 40 years. "The people picking those vegetables were displaced and had to move and find new homes. People in the world were starving because of whitefly-transmitted viruses."
Now, Osborne is frightened yet again. In 2005, University of Arizona scientists discovered a strain of pesticide-resistant whiteflies, which sparked a nationwide effort to contain the new strain. (The scary "biotype" is known as Bemisia tabaci type-Q, as opposed to the more easily contained Bemisia tabaci type-B.) The plan worked for more than ten years, but on April 25, a type-Q whitefly was found out in the wild for the very first time — in Palm Beach Gardens. On May 10, they were then spotted in Palm Beach. Then Boynton Beach and Boca Raton the next day.
Osborne and his team started ringing alarm bells. Because the fly often grows in "ornamental plants," like the hibiscus, Osborne and his team sent letters to ornamental plant growers last week, warning them of his findings. In the letter, the team begged growers not to start spraying plants willy-nilly unless they want more Q-strain bugs hanging around.
"Insecticide misuse in the United States could potentially result in silverleaf whitefly populations that cannot be controlled," the letter said. "It is important to remember that the Q-biotype whitefly is already resistant to a number of products commonly used."
Speaking to New Times, Osborne compared the new bugs to the antibiotic-resistant bacterial "superbugs" beginning to plague the medical community. "You could substitute 'whitefly' for 'bacteria,'" he said.
Palm Beach County farm owners are likely well aware of the whitefly already: In 2012, the Rugose spiraling whitefly descended upon the county and started wiping out crops left and right.
"We were thinking it was a Q; turned out to be just the B-biotype," Osborne said. "There were some really good consultants and pest control companies that were seeing a problem and called us. We sent whiteflies to the diagnostic lab, and it saved everybody’s bacon."
This time around, Osborne is far more worried. Though the Q-type bugs were eventually traced to a Boynton Beach hibiscus grower, the cat is now out of the proverbial greenhouse. To stop the fly's spread, there are only a few options. Most obviously, one can wait until effective chemicals are developed, but Osborne said there are a few species of bugs that naturally prey on the whitefly — a tiny wasp called Encarsia, which lays eggs inside the whitefly, and the Delphastus beetle.
"I just had 300 Encarsia delivered on Friday," he said. "We will prevail, but it's going to take some time."
In the meantime, he encourages anyone with a whitefly problem to stash the dead flies in a freezer overnight, and then send them to county pest control. For more information, check out the University of Florida's page on the Q-type whitefly.
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