Adult Diaprepes citrus weevil. Photo courtesy of U.S. Department of Agriculture/Agricultural Research Service. Click here for high-res image.
GAINESVILLE, Fla. — The Diaprepes citrus weevil is often more abundant in finely textured, poorly drained flatwoods soils than in the sandy soil varieties of Florida’s Central Ridge; perhaps that’s because sandy soils seem to host more species of nematodes that prey on insects.
Researchers with the University of Florida’s Institute of Food and Agricultural Science have taken those observations and turned them into a potential management technique, using “transplanted” soil and nematodes to grow flatwoods citrus. Their results appear in the January issue of the journal Biological Control.
In the study, researchers conducted experiments at a weevil-infested flatwoods citrus grove in Osceola County. They planted 50 trees in oversized holes filled with sand, and 50 trees in native soil, then introduced predatory nematodes to most of the trees. For the next four years, researchers monitored nematode and weevil populations and checked tree health.
The results showed there were more predatory nematodes of more species — and fewer weevils — in the root zones of trees planted in sandy soil. By the study’s end, 21 trees in native soil had died of weevil herbivory, compared with three trees in sandy soil. Surviving trees in sandy soil also had 60 percent greater trunk diameter and produced 85 percent more fruit than those in native soil.
GAINESVILLE, Fla. –– Tropicana Products Inc., a division of PepsiCo Inc., has pledged $1.5 million to endow a professorship specializing in innovative citrus research to strengthen the Florida citrus industry, the nation’s largest, University of Florida and Institute of Food and Agricultural Sciences officials and company representatives announced today.
The endowment, to be known as “The Tropicana Professorship for Florida Citrus Innovation,” will support teaching, research and outreach efforts dedicated to the future of the state’s citrus industry.
GAINESVILLE, Fla. — The quest to develop a grapefruit hybrid that will not interact with medication has taken a step forward, as researchers pinpoint compounds most responsible for the problem, a University of Florida citrus breeder says.
The data were published in the December 2012 issue of the journal Xenobiotica.
Scientists have been aware of the so-called “grapefruit juice effect” since 1989. Compounds in the fruit called furanocoumarins inhibit the action of an enzyme that breaks down certain medications in the human digestive system.
The phenomenon poses a health risk because it can produce unexpectedly high levels of these medications in a patient’s bloodstream. Doctors, pharmacists and prescription drug labels warn patients to avoid grapefruit and related products under these circumstances.
GAINESVILLE, Fla. — University of Florida researchers have created a mathematical model that shows how citrus greening is transmitted within an infected tree – an important step toward helping scientists understand the devastating disease.
The model, published this month by the journal Proceedings of the National Academy of Sciences, revealed that once a tree is infected, insecticides to control the pests that spread the disease may not be enough to halt the disease’s progression in the tree, and instead may only slow its spread within the tree.
Photo cutline at bottom. Click here for high-resolution image.
GAINESVILLE, Fla. — Jacqueline Burns, director of the University of Florida’s Citrus Research and Education Center, now has another hat to wear – she’s been named to lead UF’s Southwest Florida Research and Education Center in Immokalee.
Jack Payne, UF senior vice president for agriculture and natural resources, appointed Burns in early July. She will officially take the post Aug. 1.
“Dr. Burns has been doing an outstanding job at the Citrus REC, and I know she’ll bring the same passion and work ethic to Immokalee,” Payne said. “I want to thank her and express my full confidence that she will carry out her new responsibilities with distinction.”
Burns succeeds John Dunckelman, interim director of the Immokalee center since 2010. Dunckelman was hired in 2004 as associate director and will remain with the center as farm manager.
Click here for high resolution photo. Caption at bottom.
GAINESVILLE, Fla. — University of Florida researchers have discovered a natural compound to battle insect pests that plague gardeners and growers.
The compound boosts crops’ resistance to pest attacks on their roots by recruiting microscopic worms that kill the insects by eating them from the inside out.
Researchers, including members of UF’s Institute of Food and Agricultural Sciences, made the discovery by studying chemicals released by citrus roots when they are attacked by citrus root weevil larvae. Their results are published in the June 27 edition of the online journal PLoS ONE. (more …)
GAINESVILLE, Fla. — Since 2000, the University of Florida’s Plant Science Research and Education Unit in Citra has been “an idea place” where new crops and production techniques are tested.
Now, it’s a place where new ideas can be communicated to UF faculty, students and guests much more easily.
At a May 15 ceremony attended by several hundred guests, UF officials dedicated the unit’s new 12,000 square-foot conference center, the Frank Stronach Plant Science Center, named for the donor who funded the building project.
“Today, we gather to dedicate more than a building—it’s an idea place,” said Jack Payne, UF senior vice president for agriculture and natural resources.
That sentiment was echoed by several other speakers, including UF President Bernie Machen, who noted that many of the crop varieties developed by UF plant breeders get their first real-world field trials at the unit.
Though the 1,068-acre unit has always had plenty of room for cultivating plants, it’s only now that there’s enough teaching space, said Danny Colvin, the unit’s director.
Greening-infected citrus trees emit a fragrant chemical called methyl salicylate, said study author Lukasz Stelinski, an assistant professor with UF’s Institute of Food and Agricultural Sciences. Citrus trees release the same chemical, in the same amount, when under attack by the Asian citrus psyllid, the insect that transmits the bacterium.
When the pests encounter a faint whiff of methyl salicylate they interpret it to mean that other psyllids have found a good place to feed, and hurry to join the banquet. One experiment in the study showed that psyllids were more likely to land on infected citrus trees than healthy ones.
GAINESVILLE, Fla. — University of Florida researchers are working to speed up their ability to create new tangerine varieties by pinpointing the compounds that make them taste and smell the way they do.
In the last decade, Florida fresh citrus growers have lost valuable ground to producers in California and Spain who’ve enjoyed success with seedless Clementine varieties, such as the “California Cutie.” Grown in Florida, the same varieties have more seeds than consumers like.
But UF researchers at the Institute of Food and Agricultural Sciences believe their work is laying the foundation for Florida citrus producers to regain that lost ground. (more …)
Since 2006, the bacterial disease citrus greening has cost Florida’s economy an estimated $3.63 billion in lost revenues and 6,611 jobs by reducing orange juice production, according to a new study from the University of Florida’s Institute of Food and Agricultural Sciences.
The study is the first complete assessment of greening’s economic impact on Florida, said Jack Payne, UF senior vice president for agriculture and natural resources. He called the study an important step in the fight against greening, because it quantifies damages and could show legislators and funding agencies why the invasive disease is one of the state’s biggest challenges.
“This study shows plainly just how imperative it is that we find a cure for citrus greening,” Payne said. “We have dedicated a huge amount of IFAS resources toward that end, and we are very appreciative of the significant support our research is receiving from the citrus industry. Growers are the people most obviously impacted, but the study demonstrates that many other Floridians are hurt as well—when fewer oranges are harvested, there are fewer dollars circulating in our state’s economy.”
First detected in Florida in 2005, greening causes citrus trees to drop fruit prematurely and eventually kills the trees. The disease is caused by a bacterium, and was first described in 1919 in China. The bacterium is transmitted by an invasive insect, the Asian citrus psyllid.
The study compares actual harvests of oranges used to make juice with projected harvests that would have taken place if greening had never struck Florida groves; it covers the growing seasons from 2006-2007 through 2010-2011. During those five years, the disease caused substantial crop losses, said citrus economist Tom Spreen, a professor with the UF/IFAS food and resource economics department.