Now that the Asian citrus psyllid has been discovered in Louisiana, Louisiana State University AgCenter agents learned what to search for to help stop it.

Agents from the citrus-growing regions of the state attended a training session in July to learn how to identify the pest and how to deal with calls from concerned citrus growers.

In addition to classroom training, the agents learned to identify the pest on citrus trees in Jefferson Parish.

Natalie Hummel, LSU AgCenter entomologist in Baton Rouge, says the pest is known to transmit greening disease, which could cause significant damage to state's citrus industry.

"We are trying to be proactive in the control of this disease since we seem to have caught it in its early stage of infection," she says.

The first infected tree in the state—a lime—was discovered in a backyard in New Orleans in Orleans Parish in June. It was destroyed.

Since that first infestation was discovered, the Louisiana Department of Agriculture and Forestry and the U.S. Department of Agriculture have begun to survey citrus trees from New Orleans to Calcasieu Parish to determine the extent of the problem.

A quarantine has been placed on citrus trees moving out of the affected areas of the state.

Bobby Fletcher, the LSU AgCenter's area horticulture agent in Terrebonne Parish, says the pest has been found in a wide area of southern Louisiana.

Asian citrus psyllid has been in Jefferson, Lafourche, Orleans, Plaquemines, St. Charles and Terrebonne parishes, he says.

One of the challenges in battling greening is the latent period between when a plant is infected and when it starts to show symptoms, says Don Ferrin, LSU AgCenter plant pathologist. It's possible that a tree could be infected with greening disease and not show any signs for six months to two years.

"For this reason, we feel that getting our people aware of what to look for just puts us that much further ahead in trying to slow down this pest and the disease," he says.

Hummel says the insect was first identified in Florida citrus in 1998, and greening disease first appeared there in 2000. At the time, Florida officials realized the insect and greening disease were widespread across the state.

Texas is the only other state with the insect at this time, but greening disease has not been found there, she says.

Hummel, who has been working intensely in the search for this pest, says the plan is "to get out there in our commercial areas with an aggressive plan so we can keep the pest populations low to hopefully prevent widespread occurrence of the greening disease."

The disease has no treatment, so the only thing growers can do if they find the disease is to remove the diseased trees, says Dale Pollet, LSU AgCenter entomologist. And once a tree is infected with greening, it can act as a disease reservoir for psyllids.

"The nymph can get infected and will continue to carry the disease through adulthood," he says. "You can have up to 30 generations of this pest per year."

Greening is harmless to humans, but it causes a quick decline in tree health, eventually killing it. The disease gets its name from one of its classic symptoms—fruit remain green and never color up.

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