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- Psylla, citrus greening find raises red flags
- You've got pest-alert mail
- CD provides multimedia information on soil quality

Psylla, citrus greening find raises red flags

News that the Asian citrus psyllid has been confirmed in six locations in Tiajuana, Mexico, only 1.9 miles from the California border sent shock waves through the state's citrus industry. This comes a few weeks after the psyllid and the deadly citrus greening disease it spreads was confirmed in New Orleans.

"It's shocking," Joel Nelsen, president of the Exeter-based California Citrus Mutual, says about the finds in Mexico.

The insects were not discovered by the U.S. Department of Agriculture's Asian citrus psyllid trapping program, he says. Instead, they were picked up by a general pest trapping program.

"It's extremely disconcerting for it to be discovered so close to San Diego County, where there's ample enough host plants," Nelsen says. "It's created major activity on our part."

Nelsen says the industry is still waiting to hear from the USDA whether those psylla from Mexico carried the greening bacteria.

On Monday, the state's citrus greening industry task force will hold a conference call to evaluate its course of action, Nelsen says.

The California Department of Food and Agriculture is wrapping up its annual survey for the psyllid and greening and has not detected either pest, says Jay Van Rein, a department spokesman in Sacramento.

Inspectors annually survey about 25 percent of commercial citrus groves, as well as other high-risk areas, such as packinghouses and nurseries, where the pest might enter.

In light of the Tijuana finds, Van Rein says the state will tack additional psyllid traps onto its regular pest monitoring program.

New Orleans homeowner finds bug

The Louisiana Department of Agriculture and Forestry in Baton Rouge has an inquisitive New Orleans homeowner to thank for the discovery of the psyllid and citrus greening, says state entomologist Tad Hardy. She saw an unusual insect on her lime tree and looked it up on Google.

"Very quickly she got quite a bit of knowledge about the insect and the disease," Hardy says.

The homeowner then sent a couple of digital images of the pest to a local Louisiana State University AgCenter Extension agent, who identified it as an Asian citrus psyllid.

The state, working in conjunction with the USDA's Plant Protection and Quarantine division, collected samples of the pest and foliage shortly after Memorial Day.

The insect identification was confirmed by USDA's facility in Beltsville, Md., in late May, whereas the USDA confirmed the foliage was positive for citrus greening earlier this month.

On the lookout

The state and PPQ have conducted delimiting surveys within a 1-, 5- and 10-mile radius of the positive tree. In addition, they continue to survey neighboring parishes for the pest and disease.

So far, Asian citrus psyllid has been confirmed in Orleans Parish, where New Orleans sits, as well as Jefferson, Plaquemines and St. Charles parishes, Hardy says.

Of the nearly 90 foliage samples that have been sent to Beltsville, about half have come back negative for citrus greening. Hardy says results on the other samples are pending.

The only positive greening samples are from the homeowner's lime tree, he says.

The infected lime tree had been in the ground for about three years. Before that, it was in a pot. The homeowner originally received the tree as a gift.

The source of the disease and psyllid may never be known, Hardy says.

"At this point, we really don't know," he says. "We certainly don't know if it's the only problem or the start of a problem. We don't know if this is the epicenter of the population."

Greening and the psyllid elsewhere

Citrus greening, also known as huanglonging or HLB, is lethal to citrus, reducing yields and killing trees in a matter of years. The disease was first confirmed in the United States in Florida in September 2005, about seven years after the initial Florida discovery of the Asian citrus psyllid.

It spread to most of Florida's citrus-producing counties in a matter of months, and state agricultural officials have given up hope they can eradicate it or the Asian citrus psyllid.

Texas has had the Asian citrus psyllid since 2001, and 37 southern counties remain quarantined. But so far, agricultural officials have not detected citrus greening, says Julian Sauls, a professor and Extension horticulturalists at Texas AgriLife's research station in Weslaco.

"We hope that means that the psyllid that came here didn't have the greening bacterium in its system," Sauls says. "But that's not to say there's a tree somewhere in the state that doesn't have it. We still look every year from here up to Houston, because we don't need [greening]."

A cooperative approach

Members of Texas Citrus Mutual, Florida Citrus Mutual and California Citrus Mutual met recently by conference call and agreed to adopt Florida's citrus health response plan, Nelsen says.

They also agreed that more money needs to be allocated toward the fight. That includes funding for additional dog teams to detect possible contraband being brought into California and more inspections at the Arizona border. In addition, they want money put toward developing faster disease detection tests in California.

Members agreed that the Asian citrus psyllid is still confined within Texas, and they hope to seek a permanent psyllid eradication program in that state.

For more information about greening symptoms and the Asian citrus psyllid, visit http://edis.ifas.ufl.edu/PP133.

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