A disease devastating Florida's $9 billion citrus industry might be halted with a chemical used as a treatment for gout in humans, researchers in the state say.
Citrus greening disease, caused by a bacteria deposited on the trees by an insect called the Asian citrus psyllid, has affected almost 70 percent of Florida's citrus crop, they said, making finding a treatment a top priority.
"We're really hopeful," University of Florida researcher Graciela Lorca said, after the chemical slowed the progress of the citrus disease in 80 percent of trees in an experiment conducted at the university.
The researchers in the university's Institute of Food and Agricultural Sciences spent three years testing around 1,200 compounds, looking for one effective against the proteins that help the bacteria's survival in the trees, she said.
Three compounds were found to be effective, she said; hexestrol, phloreting, and especially benzbromarone, which is used in treating gout in humans.
"We are actually looking at how the bacteria is dying in the plant," Lorca said.
Tree shoots from an infected tree sprayed with benzbromarone saw an 80 percent reduction in the bacteria, the researchers said.
Citrus greening disease causes yellowing in the trees' tissues and leaves, leading to premature loss of leaves and eventually the death of the tree.
Previously the only treatment was removing the infected trees to keep the bacteria from spreading throughout a citrus grove.
The disease has cost Florida's economy $4.5 billion since 2006, the researchers said, with the loss of some 6,700 jobs due to decreased orange juice production.
"Every grower I know is just hanging by their fingernails, hoping and praying for a new discovery for treatment," Ellis Hunt Jr., whose family has grown citrus since 1922, said in a university press release.
The disease was also discovered in California citrus groves in 2012, and researchers in the state are also looking for ways to combat it.
Although tests have been encouraging, citrus industry experts have said they expect it will need 5 to 7 years before an active-ingredient treatment based on benzbromarone would be commercially available on a wide basis.
One of the main factors to determine before that would be if the chemical would have any effect on citrus fruit's taste, they said.
It would also require approval from the U.S. Department of Agriculture and the regulatory agencies in the affected states, they note.
The researchers have published their study results in the journal PLOS Pathogens.
