As USDA eases Florida's canker limits, greening problem grows
by C. Baxter Carter | July 07, 2009
BONITA SPRINGS, FL -- After a decade of bad news, the beleaguered Florida citrus industry finally had cause for celebration at its annual conference held here June 24-26.
Research spearheaded by Tim Gottwald, a Florida-based plant pathologist with the U.S. Department of Agriculture's Agricultural Research Service, found that the virulent canker that has plagued Florida citrus for the past decade is not transmissible by blemished fruit, and the USDA has recommended the shipment of citrus from Florida groves be allowed to resume without restriction. The USDA published the proposed change June 30; there will be a 60-day comment period before it goes into effect.
The good news was delivered by Paul Hornby, Florida plant health director of the USDA's Animal & Plant Health Inspection Service, who said that the "risk of spreading citrus canker via fresh fruit is less than thought."
Dan Richey, chief executive officer of Riverfront Packing Co. and a former chairman of the Florida Citrus Commission added, "The science is irrefutable -- the risk is infinitesimal." He said that the "jungle" of canker-related regulations that had restricted shipments of fresh Florida citrus to other citrus-producing states and international markets since 2006 "turned the fresh industry into a juice industry." Before the quarantine, Florida shipped 1.5 million cartons of fresh citrus annually to Arizona, Texas and California.
The good news was tempered by reports that the Asian citrus psyllid, a tiny bug that spreads citrus greening via the lethal Huanglongbing bacteria, more commonly referred to as HLB, has been found in all 32 Florida citrus- producing counties, and the state industry has launched "our own Manhattan Project" to fight the disease, said Michael Sparks, executive vice president and CEO of Florida Citrus Mutual.
The canker virus first appeared in Florida in 1910; it was eradicated in 1933 before turning up again in 1986. In 1994, that outbreak was declared over, but just a year later, canker was found in Dade City. In 2006, the USDA declared the battle against canker unwinnable and left eradication efforts in the hands of Florida growers and shippers.
The new research shows that canker blemishes on fresh fruit are nothing more than "a cosmetic defect," Mr. Richey said.
Other citrus-producing states are leery of the regulatory change. "It's a 180- degree switch from what we were all led to believe" Joel Nelsen, president of California Citrus Mutual, told The Produce News. "There are 35,400 growers out here, and they overwhelmingly believe canker can be moved in a variety of manners, movement of fruit being one of them."
Mr. Nelsen said that CCM will establish an expert panel to review the proposal, which "basically indicates that as long as a commercial packinghouse continues to agree to do business the way they have, you can move fruit anyplace you want. If the science ... justifies that, they'll tell us, and we'll comment accordingly."
California Department of Agriculture spokesperson Steve Lyle said the rule would be reviewed and a comment possibly submitted.
G. John Caravetta, associate director of the Arizona Department of Agriculture, told The Produce News that the state "intends to review the APHIS proposal and supporting documentation thoroughly. We will engage our stakeholders and formulate a response once we have a thorough understanding of the science supporting the proposal [and] risk mitigation procedures."
Veronica Obregon, chief communications officer for the Texas Department of Agriculture, said that the state "is extremely concerned about changing the longstanding practice of prohibiting the movement of citrus from a canker- infected area into another citrus-producing area that is free of this destructive disease."
When it comes to HLB, the states are more in accord. Mr. Sparks said that the state industry has "established a great rapport" on the bacteria with Texas and California because "they've seen the devastation" the disease has caused in Florida. Currently, the only recourse for HLB is to remove infected trees. The Asian citrus psyllid first entered the United States in 1986 via the port of Miami, though the first HLB infection was not seen until 2005. The bacteria spreads rapidly, and infected trees die in two years or less.
Florida expects the results of aerial grove surveys being conducted this summer to show a dramatic reduction in acreage. Citrus production could dip below 140 million boxes (from a peak of 200 million) within three years. More than 100 HLB research projects are underway. Short-term efforts focus on management; long term, researchers are looking to develop an HLB- resistant crop. Mutual spokesperson Andrew Meadows said, "There are some trees in the field that show some resistant capabilities," but finding out why will take at least 12 to 18 months, and developing trees with the same traits could take 15 years.
"It's only a matter of time" before other citrus-producing states have to deal with the bacteria on the same scale as Florida, said Mutual President Fran Becker.
In California, discovery of HLB in Florida led to a state task force to address the threat. "As a result, when [Asian citrus psyllid] was found in Tijuana, Mexico, the state of California was able to immediately survey for the pest north of the Mexican border," said Mr. Lyle. "Rapid response with a local treatment program has effectively eliminated ACP wherever it has been found."
In Texas, a newly organized task force will provide guidelines on minimizing the psyllid population, protecting citrus nurseries, and developing a citrus greening management plan, Ms. Obregon said.