The Visalia-based California Citrus Research Board on Friday enlisted the help of master gardeners, homeowners, landscape managers and growers in the San Diego area to search for a deadly insect that could devastate the state's citrus industry.
Ted Batkin, who heads the board, called the pest a "huge threat" to the $1.3 billion California citrus industry, 80% of which is in the central San Joaquin Valley.Interviewed by phone from San Diego, he said recent discovery of an established breeding population of the Asian citrus psyllid in Mexico "stirred us into a whole different mode."On Thursday, leaders of the citrus industry and top scientists from the Valley traveled to San Diego to give briefings on the pest. It is the only known transmitter of a bacteria that results in "greening," officially called by its Chinese name, huanglongbing.That disease may have destroyed as many as 65,000 acres of citrus in Florida. It has not been detected in California.The disease can lie dormant for two years, said Bob Blakely, director of grower operations for California Citrus Mutual in Exeter. That means it can be transmitted throughout a grove by "a domino effect" before damage begins to show, he said.Not only does it turn fruit bitter, it kills the tree. Blakely said greening is much worse than citrus canker, which also has plagued Florida growers but has not been found in California. Canker can be treated, greening cannot. Asked if the threat is similar to that posed by the glassy-winged sharpshooter insect pest that can spread Pierce's Disease in a vineyard, Batkin said there is an analogy -- with one notable difference."There are things you can do to combat Pierce's Disease," he said. "There's no cure for this. Once the bacteria is spread in a tree, it's a goner."The research board, working with government agencies and others, has what it calls a "sentinel tree" program it is putting into place, starting in San Diego. To help bait and trap the bug, it involves pruning trees to encourage new growth the psyllids favor. Normally, this time of year there would not otherwise be new growth.The board, funded by state growers, also will set up labs in Riverside and Tulare counties to expedite testing for the disease on suspect trees.Blakely said a task force has been preparing a plan to respond to any infestation for more than a year. The state's industry hopes to avoid the kind of delay that occurred in Florida, where there was not an immediate response because it was thought the deadly bacteria was not present. The disease needs two things: the bacteria to be present in a tree and the pest to spread it."If the bacteria is in this state, this pest will find it," Batkin said. "We have not found it, but we suspect it is there."Blakely said one source could be ornamental nursery plants, notably orange jasmine, that could harbor the bacteria. Batkin said it's most likely the insect pest could be found in an urban setting. There have been previous finds of the psyllid at airports in San Francisco and Los Angeles.He said it's highly likely the psyllid is in California, due to the Tijuana infestation, because it can be carried by winds and can fly about 3 miles "on its own."