After years of genetic sequencing, University of Florida researchers are beginning to harness the insects’ ability to churn wood into fuel. That ability involves a mixture of enzymes from symbiotic bacteria and other single-celled organisms living in termites’ guts, as well as enzymes from the termites themselves.

The team from UF’s Institute of Food and Agricultural Sciences spent two years dissecting and analyzing gene sequences of more than 2,500 worker termite guts. In total, they identified 6,555 genes from the termites and associated gut fauna involved in the digestive process.

As the researchers reported Oct. 15 in the online journal Biotechnology for Biofuels, they’ve begun to identify which of these genes encode for enzymes that could significantly improve the production of cellulosic ethanol, a fuel made from inedible plant material that the U.S. Department of Energy estimates could replace half of our gasoline if the production process could be made more cost effective.

“Termites are very unique creatures, and this research helps give the most complete picture of how their systems collaborate to, very efficiently, break down really tough biological compounds to release fermentable sugars,” said UF entomologist Mike Scharf, who leads the research.

The team has identified nearly 200 associated enzymes that help break down the problematic plant compound lignocellulose. This compound is the most costly barrier to wide-scale production of cellulosic ethanol because it must be broken down by intense heat or caustic chemicals.

Termites, however, are able to almost completely break down lignocellulose through simple digestion.

“The termite gut is a complicated and exotic package of biodiversity that manages these tasks with an efficiency that you really have to admire,” said Claudia Husseneder, a specialist in the molecular biology of termites at Louisiana State University who was not associated with UF’s research. “Mike’s work is on the cutting edge of understanding this system.”

In September, Scharf and the Savage, Maryland-based Chesapeake-PERL Inc., received a $750,000 grant from the U.S. Department of Energy to help develop his work into a product that can be used to help manufacture cellulosic ethanol.

Termites and their associated single-cell symbiotic organisms probably won’t have much to do with the processes that result from the work-except for their genes, of course. Scharf said that enzyme-producing genes will be transferred to a more controllable creature.

This has commonly meant that the genes would be transferred into genetically modified fungi or bacteria. However, Scharf said the genes would likely be transferred into other insects, such as caterpillars, to produce the enzymes on an industrial scale.

“Insects have played an important role in how this planet functions for millions of years,” Scharf said. “They still have a lot they can teach us. There are still many ways we can learn to benefit from Earth’s six-legged inhabitants.”

Contacts:
Writer: Stu Hutson, 352-273-3569, stu@ufl.edu
Source: Mike Scharf, 352-273-3954, mescharf@ufl.edu

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GAINESVILLE, Fla. — A century and a half ago, the nation was in the midst of unparalleled change and turmoil. The Industrial Revolution had morphed American life at its most fundamental levels, and the Civil War had reduced the U.S. political system to tatters.

With that setting, on July 2, 1862, President Abraham Lincoln signed what was dubbed the Land Grant Act. The act created funding for a nationwide higher education system-creating a network of colleges rooted in the promise of advancing the country’s agrarian industries. The effort would not only help reunite a shattered nation, it would bolster that union’s new position of world leadership.

Today’s world may seem very different. But from the view afforded by his position in the U.S. House of Representatives, Adam Putnam sees this as a time when the land-grant mission is just as important.

On Nov. 9, Putnam will share that perspective in a lecture entitled “Green-Lighting the 21st Century Land-Grant Mission,” on the University of Florida campus. As part of the York Distinguished Lecturer series, the presentation is free and open to the public.

“Whether you’re looking at the state of Florida, the nation or the world as a whole, we’re going through radical changes that demand responsible action,” said Putnam, who has represented Florida’s 12th congressional district since 2001. “Energy, the environment, water concerns, obesity, starvation-even nutrition, aging and other fundamental health issues-these are global challenges with solutions that will come from our land-grant system.”

Putnam has served on the committees on Agriculture, Budget, Government Reform, Rules and as the leader of the subcommittee on Technology, Information Policy, Intergovernmental Relations and Census.

His time in the house, however, is also marked by a strong support of agriculture that reflects the needs of his constituency. Florida’s 12th district, positioned along the I-4 corridor in central Florida, includes cattle ranches, citrus groves, small towns as well as rapidly changing communities near the metropolitan areas of Tampa and Orlando.

In fact, Putnam was born in the 12th district and was active in 4-H as well as his family’s citrus and cattle operation. He credits 4-H as being extraordinarily influential to his life and career, and touts the organization as one of the most inspirational elements of the land-grant system.

“It seems like we’re always faced with a barrage of bad news about the next generation,” he said. “But 4-H stands out as a bright spot. It not only reconnects young people to the land, it gives them a head start in science and technology in a way no other program can.”

After graduating from the University of Florida with a degree in food and resource economics, he went on to serve in the Florida House of Representatives from 1996 to 2000.

As a representative on both a state and national level, he’s witnessed a strong urbanization trend. These changes, he says, will require a strong understanding of natural resources and an agricultural community that is given the best tools available to feed a population that is growing and diversifying.

“We also have to think about how we interact on a global level-no state or country is an island,” he said. “The developing world and even other industrialized nations are struggling with new ways to power their cities and feed their populations.”

Research on renewable fuel sources, secure food sources and environmentally sound policies create a better future for us all, he said.

The lecture will be held in the Presidents Room of Emerson Alumni Hall at 2 p.m. Parking is available in the O’Connell Center lot. The York Distinguished Lecturer Series is made possible through a gift to UF’s Institute of Food and Agricultural Sciences from E.T. and Vam York.

For more information about the series, please visit http://yorklecture.ifas.ufl.edu.

Contact:
Stu Hutson, 352-273-3569, stu@ufl.edu

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GAINESVILLE, Fla. — Sugar Belle-a bold mandarin orange hybrid that ripens in time for the winter holiday market-will be the first University of Florida-created citrus variety intended for commercial production.

The mandarin hybrid-a mix of the sweet Clementine and the colorful, bell-shaped Minneola-has a rich taste and strong aroma, said UF Institute of Food and Agricultural Sciences plant breeder Fred Gmitter.

The new sweet-tart fruit may be best described as a mandarin with a tangy punch.

“Many old-timers in citrus have said this is the best-tasting citrus they’ve ever had,” Gmitter said.

The fruit, which has a patent pending and is also known as LB8-9, has been in the works since 1985.

Mark McLellan, IFAS’ dean for research, said he believes the time that went into breeding this variety will be worthwhile.

“Sugar Belle is positioned in a unique market window, and its flavor characteristics are expected to make this variety a consumer favorite,” he said. “We’re very excited to offer it on behalf of the university.”

Recently, Florida Foundation Seed Producers Inc., a direct support organization of UF, awarded an exclusive U.S. license to the New Varieties Development and Management Corporation.

Funded by the Florida Citrus Commission, the not-for-profit corporation was set up in 2005
to help assure Florida growers access to new patented citrus varieties, manage new varieties and direct resources to citrus breeding research.

The corporation was granted the exclusive license for the fruit through the university’s Invitation to Negotiate process, designed to benefit everyone from IFAS to citrus growers.

“It’s becoming more common for grower-backed organizations to help monitor the markets for growers and ensure that everyone has a chance to be successful,” said John Beuttenmuller, the intellectual property and licensing director for Florida Foundation Seed Producers, which led the ITN process.

In that process, a company is selected to deliver new cultivars to the public. In return, the company pays royalties back to the Florida Foundation Seed Producers and the Florida Agricultural Experiment Station, to be reinvested in breeding and development programs.

Sugar Belle is a unique variety, said the corporation’s executive director, Peter Chaires. He believes it will make a big splash in the $52 million specialty citrus market.

Chaires describes its flavor almost like one would describe a fine wine.

“It has a flavor that takes it to the top of the show wherever it goes. It’s got a very, very deep flavor,” he said. “I don’t want to say it’s rich, but it’s a very deep, complex flavor.”

Despite strong ties to the citrus industry, UF has never before released a citrus cultivar developed solely by its scientists-likely because citrus breeding is an excruciatingly slow endeavor. The average time for new citrus-from creation to its commercial release-can be up to 20 years.

And in this case, what became the UF’s inaugural citrus variety could just as easily have been plowed under.

Gmitter, who arrived at UF’s Citrus Research and Education Center in Lake Alfred as an assistant professor in 1985, was a young plant breeder desperate for citrus trees to work with. After locating a small tract of trees left by a retired professor, Gmitter went for a look.

“I went out in early November of my first year … This one tree had beautiful, bright orange fruit. The best citrus I’d ever eaten in my life,” Gmitter said. Those trees were used to create his new cultivar.

UF officials hope Sugar Belle will be as lucky when it comes to reaching consumers-which could be as early as this year, in some markets.

The fruit matures early, so it should be a good fit for the December holiday market, Chaires said. It can be grown in a manner to produce low-seeded fruit. And with his organization keeping tabs on how the fruit fares in groves and the economics of the citrus market, he believes the new fruit has the potential to be a big hit.

“Every time we’ve tested it with different groups, it’s been wildly popular,” he said.Contacts:

Writer: Mickie Anderson, 352-273-3566, mickiea@ufl.edu

Sources: Fred Gmitter, 863-956-1151, ext. 1301, fgmitter@ufl.edu
Mark McLellan, 352-392-1784, mrm1@ufl.edu
John Beuttenmuller, 352-392-9446, beutt@ffsp.net
Peter Chaires, 407-302-3510, pchaires@flpackers.org

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GAINESVILLE, Fla. — Dissecting owl pellets and reconstructing animal skeletons inside can be a gruesomely great educational experience for youngsters - so much so, that demand for owl pellets has spawned a cottage industry.

In Florida, one of the main suppliers is Richard Raid, a professor with the University of Florida’s Institute of Food and Agricultural Sciences.

Owls can’t chew, so they rip prey apart with their beaks and swallow it in big chunks. The pellets are blobs of undigested fur and bones the birds regurgitate after a meal.

Raid gathers 3,000 to 5,000 pellets each year from farms in the Everglades Agricultural Area. He leads workshops at schools, clubs and museums where he shows children how to carefully pick apart the pellets, identify the creatures inside, and arrange the bones into complete skeletons.

The experience may sound cringe-inducing, but it teaches children about biology and predator-prey relationships, says Raid, a plant pathologist at UF’s Everglades Research and Education Center in Belle Glade.

“I have an expression: With kids, if cute is good, gross is better,” he said. “The more unpleasant you can make something, the more it interests them.”

Raid says teachers often tell him his workshop was the most memorable lesson of the year.

“That’s gratifying,” he said.

But becoming a pellet magnate wasn’t something Raid set out to do. Instead, it developed from another project he’s pursued for more than a decade.

Raid helps farmers in the Everglades Agricultural Area install owl nesting boxes, because the birds provide low-cost, sustainable rodent control. The pests, particularly cotton rats and marsh rabbits, cause up to $30 million in damage each year to the area’s 700,000 acres of sugar cane, rice and vegetable crops.

A nesting pair of barn owls can eat 1,000 rodents per year. The area now has hundreds of nesting boxes and some of the highest barn-owl concentrations in the country, Raid says.

Along the way, he realized there was a demand for owl pellets, so Raid started gathering and sterilizing them and giving them to local teachers. These days his supply goes partly to educators. The rest are sold to biological supply dealers who pay about 50 cents per pellet, money Raid uses to support the program.

Nationwide, owl pellet gathering is worth perhaps $2 million to $3 million per year, but it’s growing at 25 to 30 percent annually, says Chris Anderson, owner of Owl Brand Discovery Kits in Portland, Ore.

Anderson’s company, founded in 1996, employs 12 full-time gatherers and ships at least a quarter million owl pellets each year, he said. They gather owl pellets from about 1,000 sites in Western states, mainly on private land.

“It’s very relationship driven,” Anderson said. “You’re asking to poke around someone’s property.”

And the job presents some unique challenges.

“I’ve had floors fall out from underneath me in old, abandoned houses,” he said. “I’ve been dive-bombed by owls.”

As raptors go, barn owls are fairly docile, Raid says, usually preferring to flee when people approach their nests. But he adds, “I’ve had a talon or two come in contact with me.”

The pellets are usually retrieved from nesting boxes, or places owls roost, such as old barns and pump houses. A barn owl can expel two or three pellets each day. The best time for gathering is in the spring and fall, because there’s little rain and pellets stay intact long enough to dry out. Here, fresh is not best, Raid says. Pellets less than 24 hours old are messy.

“For those I definitely wear gloves,” he said. “They’re the consistency of a big wad of chewing tobacco that’s just been spit out.”

Contacts:

Writer: Tom Nordlie, 352-273-3567, tnordlie@ufl.edu

Sources: Richard Raid, 561-993-1564, rnraid@ufl.edu
Chris Anderson, 503-913-2816, Chris@obdk.edu
Caption:
In this file photo released by the University of Florida’s Institute of Food and Agricultural Sciences, Richard Raid rousts a barn owl from its nesting box on a South Florida farm. Raid, a professor at the Everglades Research and Education Center in Belle Glade, encourages farmers to install nesting boxes in their fields because owls provide natural rodent control. He also gathers and distributes owl pellets, a popular item for youngsters to examine in science classes. (AP photo/University of Florida/IFAS/Eric Zamora)

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The oyster lover’s axiom of edibility — that this shellfish is safest to eat in any month with an “r” in it — may soon become somewhat of a culinary anachronism, thanks to a new food-safety test developed with help from the University of Florida.

Oysters are typically considered safest to eat in cooler months (September through April) because the shellfish-infecting bacteria in the genus Vibrio flourish best in warm temperatures.

Even in the “r” months, slurping an oyster opens some people to infection from these bacteria, which can cause fever, nausea, abdominal pain, diarrhea and has even led to finger amputation when it’s given a chance to penetrate a cut or skin lesion.

However, a new quick and inexpensive diagnostic test developed by DuPont Qualicon and refined by UF’s Institute of Food and Agricultural Sciences could make weeding out pathogen-loaded oysters much more practical and efficient. Oysters are a $14 million industry in the Sunshine State, according to the Department of Agriculture and Consumer Services.

The test is based on a technology dubbed “quantitative polymerase chain reaction,” or QPCR diagnostics. Given a small sampling of oyster, shrimp or ahi tuna, the system tracks genetic material found in three harmful species of Vibrio by amplifying their DNA into large amounts that are easily detected.

This is the first time this technology could be used in detecting pathogens in seafood on an industrial scale.
So, after initially developing the basic lab-bench test, DuPont turned to UF to prepare it for commercial use and regulatory approval.

“Whether you have raw oysters or if you’re trying to validate some sort of treatment method, the old way of testing these bacteria in oysters just isn’t very practical because it’s pricy and takes about a week,” said Anita Wright, a UF food science professor whose Florida Sea Grant work is validating and expanding applications of the new test for seafood processing and research purposes.

This USDA-funded research evaluates treatments such as freezing, high pressure, irradiation, or mild heating, and is funded by the Florida Gulf Coast Oyster Industry Council.

Wright will present findings from her work at the Oct. 17-23 biennial meeting of the Interstate Shellfish Sanitation Conference, followed by a workshop to demonstrate the methodology.

The ISSC is a shellfish regulatory cooperation that will determine if the test is reliable enough to be used industrywide. If approved, the test could be an especially big boon for oyster harvesters in the Gulf of Mexico, the source of a third of all U.S. oysters.

Warmer water temperatures and factors such as pollution make Vibrio species a major concern for Gulf-harvested shellfish. Forty percent or more of Gulf oysters carry these pathogens in the “non-r” months, according to the FDA.

�
Contacts:
Writer: Stu Hutson, 352-273-3569, stu@ufl.edu

Source: Anita Wright, 352-392-1991 ext. 311, acw@ufl.edu

Caption:

In this photo released from the University of Florida’s Institute of Food and Agricultural Sciences, food-science researcher Anita Wright demonstrates how shellfish samples are entered into a new test that can quickly and cheaply detect several strains of Vibrio, a bacteria that commonly contaminates oysters during warmer months - Tuesday, Oct. 13, 2009. The test, which Wright helped refine with researchers from DuPont Qualicon, could be a major boon to oyster harvesters in the Gulf of Mexico. The Gulf is the source of a third of all U.S. oysters, but the Food and Drug Administration estimates that forty percent of these shellfish carry Vibrio bacteria in warmer months. (AP photo/University of Florida/IFAS/Tyler Jones)

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The Caribbean spiny lobster is one of Florida’s top commercial seafood species, with an annual $27 million harvest — but a recently discovered virus is killing the crustaceans and threatening the industry.

Now, scientists with the University of Florida and several other institutions have been awarded a three-year, $1.4 million National Science Foundation grant to research transmission of the virus, known as PaV1.

The research should answer many lingering questions about the spread and geographic distribution of the pathogen, and could lead to management strategies and new methods for identifying infected lobsters, said Don Behringer, an assistant professor with UF’s Institute of Food and Agricultural Sciences.

One of the main issues to be investigated: whether the virus is dispersed long distances by lobster larvae, which float hundreds of miles during their first months. Infected spiny lobsters have been found in far-flung places, including the Florida Keys and parts of Mexico, Belize and St. Croix.
“This project will give us insight into how pathogens are spread in the marine environment,” said Behringer, a co-discoverer of the virus. “Anything we can do to understand how the disease spreads, and how we might limit its spread, has implications for management of the disease.”

If the study confirms that PaV1 is spread by lobster larvae, that would have implications for other species and other diseases, because many marine animals go through a free-floating larval stage, said Mark Butler, a professor with Old Dominion University in Norfolk, Va.

During the project, researchers will examine possible forms of virus transmission, the virus’ effects on lobsters, and factors influencing local disease outbreaks, Butler said. They will also hold workshops for fishermen and resource managers in Florida and the Caribbean.

The virus was discovered in 1999 by Behringer, Butler and Jeffrey Shields with the Virginia Institute of Marine Science. Many of the early findings regarding PaV1 epidemiology came while the team was working at the Keys Marine Laboratory located on Long Key. This work showed that the disease primarily kills juvenile spiny lobsters, though some become infected without apparent harm.

The PaV1 virus attacks blood cells and tissues, causing lobsters to become listless and solitary, Behringer said. Most eventually die from metabolic depletion, a condition characterized by loss of energy.

Beginning with the 2000-2001 lobster season, harvest declined approximately 30 percent from previous harvest years and has yet to rebound, said John Hunt, a longtime lobster biologist and program manager with the Florida Fish and Wildlife Conservation Commission.

Hunt said he believes the virus is a likely cause of the reduction.

Florida produces more than 90 percent of the nation’s spiny lobster; in 2007 the harvest was about 3.8 million pounds, with a dockside value of $27 million, according to the Florida Department of Agriculture and Consumer Services. Recreational lobster diving is also a significant tourist industry.

The Caribbean spiny lobster is found in the Gulf of Mexico, Caribbean Sea and western Atlantic Ocean, from Bermuda to Brazil, Behringer said.

In the United States, spiny lobster represents less than 10 percent of national lobster production, with Maine lobster accounting for 90 percent or more, according to the U.S. Department of Agriculture. Worldwide, Maine and spiny lobster each represent about one-third of the total harvest.

The research team includes faculty and students from UF, Old Dominion, the University of Miami and the Virginia Institute of Marine Science.

Behringer, Butler and other members of the research team are researching methods for managing PaV1, with funding from the Florida Sea Grant program.

Contacts:
Writer: Tom Nordlie, 352-273-3569, tnordlie@ufl.edu
Sources: Don Behringer, 352-273-3634, behringer@ufl.edu
Mark Butler, 757-683-3609, mbutler@odu.edu

Caption:
In this file photo released by the University of Florida’s Institute of Food and Agricultural Sciences, researcher Don Behringer, right, trains student intern Michael Dickson to identify Caribbean spiny lobsters infected with the virus PaV1, at a laboratory on Long Key. Behringer is part of a research team that was just awarded a $1.4 million grant to study transmission of the virus, which often kills infected lobsters. In 2007, Florida’s spiny lobster harvest was worth about $27 million. (UF/IFAS photo by Ian Maguire)

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GAINESVILLE, Fla. — Good news for your utility bills and the environment: New University of Florida research shows that landscape shrubs need much less water to establish healthy roots than you might expect.

“We finally have our irrigation recommendations for establishing shrubs backed up with science. We need less irrigation than many people think,” said Ed Gilman, a UF Institute of Food and Agricultural Sciences environmental horticulture professor who led the research study.

The six-year study’s objective was to determine how best to irrigate shrubs during “establishment” — the 20- to 28-week period when shrubs’ roots grow until the plant can survive without irrigation.

The research examined irrigation frequency and volume on the quality, survival and growth rates of three-gallon, container-grown shrubs. Plants were examined in Fort Lauderdale, Balm, Apopka and Citra, locations that span three water management districts in Florida and have varied growing conditions.

Some of the state’s most popular ornamental shrubs were evaluated, including both native and non-native species, such as yaupon holly and gardenia.

“One of the results that we noted was that there are no differences between native and non-native species for amount of water required for establishment, “Gilman said. “This often surprises people, but it emphasizes that the Florida-friendly principle — right plant, right place — is worth following.”

Florida-friendly gardening means planting that accounts for site conditions, maintenance needs and local climate. Such landscapes may use both native and non-native plants, as long as the non-native plants aren’t an invasive species.

Regular irrigation in the months after planting helps shrubs remain healthy and attractive as they establish. But one eyebrow-raising study finding is that light, frequent watering is much more efficient and effective than applying large volumes less frequently.

North of Orlando, Gilman recommends using as little as 1 gallon of water per shrub, applied every eight days. In South Florida, he recommends every four days.

More frequent irrigation, such as every four days in North Florida and every two days in South Florida, does result in more vigorous plant growth. But applying more than 1 gallon per irrigation doesn’t increase survival or growth, he said.

“Results showed that applying large volumes of water cannot compensate for infrequent irrigation,” Gilman said. “This means that you should water more often, but with less water at each irrigation event. That helps the plants achieve proper establishment and, in turn, means less watering in the long run.”

Gardeners should maintain their irrigation schedule until shrubs survive on rainfall alone, once roots have grown to the edge of the foliage canopy, usually within 28 weeks of planting.

In long hot, dry spells, occasional irrigation may be needed after shrubs are established. Such weather can occur at any time in Florida, but is most likely in the spring and fall - April, May, October and sometimes November.

In the first year after planting, use 1 to 2 gallons of water when there is less than a quarter inch of rain within a two-week period. Drought-sensitive shrubs, such as holly fern and wild coffee, may need more frequent supplemental irrigation, while drought-tolerant shrubs, like Burford holly, may need very little.

The study can be found at http://hort.ifas.ufl.edu/irrigation. Or check out the fact sheet Establishing Shrubs in Florida Landscapes, http://edis.ifas.ufl.edu/EP391, for more information.

Several simple steps can help ensure your plants survive establishment:
· Consider planting at the start of the rainy season.
· Irrigate based on location, weather and desired plant vigor.
· Apply water directly to the rootball.
· Use low-volume irrigation. Don’t irrigate if a quarter-inch or more rain fell in the last 24 hours.
· After establishment, irrigate when there are signs of wilting, but before leaves begin to die.

Contacts

Writer: Emily Eubanks, 352-392-1831, eee@ufl.edu

Source: Ed Gilman, 352-262-9165, egilman@ufl.edu

Photo cutline

A new study by UF Institute of Food and Agricultural Sciences researcher Ed Gilman says gardeners who wish to establish healthy shrubs need far less water than they likely think. (Tyler Jones/IFAS)

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GAINESVILLE, Fla. — It’s bad enough that the Southeast is bedeviled by a tick that doesn’t mind taking up residence inside homes.

But now researchers say they believe the brown dog tick has developed resistance to the treatments most commonly used to fight it.

University of Florida researchers Phil Kaufman and Faith Oi will work with USDA tick expert Robert Miller to test the ticks’ resistance to permethrin, a chemical found in many pesticides and repellents, and fipronil, found in Frontline. Both are sold in pet stores.

A $171,000 grant from the USDA’s Southern Region Integrated Pest Management Center will support the researchers’ three-year study. When it ends, they hope to know the tick’s level of resistance to both chemicals and to have an array of materials aimed at teaching the public how best to guard against infestations and what to do if they face one.

The brown dog tick has been invading homes across the Southeast for years, Kaufman said, but its resistance to chemical foes seems to have been building the last five to eight years. This study will be the first to document the ticks’ resistance in the U.S.

“The challenge now is in people not being able to control or knock out the ticks with some of the pesticides,” he said. “And for controlling this particular tick, pesticides are almost essential.”

Having one’s home infested with the brown dog tick is nothing short of miserable. While they’re not generally known for spreading disease to humans, they are often described as “predatory,” lying in wait for whatever organism will provide their next blood meal, whether it be dog - or human.

The ticks are small — about the size of a match head — before they get a blood meal and grow noticeably bigger. Before that, they’re tough to see, leaving homeowners to often miss the first signs of an infestation, especially when even tinier larvae and nymphs are present.

The first indication often comes when residents see ticks crawling up the walls or curtains.

“I always tell people it’s a minimum of a six-month ordeal and oftentimes, up to a year to clear an infestation,” Kaufman said. “One female tick can lay 5,000 eggs. And if you miss one tick, and she lays those eggs — you’re starting over.”

Part of the problem likely lies in pet owners’ good intentions, the researchers say. Pet owners don’t like the idea of pets with fleas or ticks, so they buy pesticides that come in handy one-month doses, and then treat for ticks and fleas whether they’re present or not.

That type of preventative spraying and dosing is typically reserved for pests that can kill us or our pets, Kaufman said, such as heartworm.

Under the tenets of Integrated Pest Management, researchers work to keep pesticides viable as long as possible by encouraging people not to overuse them, and to employ other techniques instead.

That means carefully monitoring one’s dog for any sign of ticks, shampooing the dog and physically removing ticks before they gain a foothold, vacuuming frequently and ensuring that hedges and underbrush where ticks can hide are kept cut back.

While the brown dog tick isn’t a major disease threat to humans, it falls into the same “creepy crawly” category as bedbugs or fleas, said Faith Oi, an assistant extension scientist with UF’s entomology and nematology department.

“They’re bloodsucking insects,” she said. “It’s a difficult problem once the populations get high because they’re very good at getting into cracks and crevices. If you know where to treat, that’s one thing, but if you don’t even know where they are, it gets more difficult, and then you have to keep going back and back and it’s a very long process to get a handle on.”

Contacts

Writer: Mickie Anderson, 352-273-3566, mickiea@ufl.edu

Sources: Phil Kaufman, 352-273-3975, pkaufman@ufl.edu

Faith Oi, foi@ufl.edu

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University of Florida entomology researcher Phil Kaufman and assistant extension scientist Faith Oi examine a blood-fed brown dog tick in a lab at the Gainesville, Fla. campus. The researchers and a USDA tick specialist have received a three-year grant to evaluate whether the species has become resistant to the pesticides most commonly used to fight it. (Tyler Jones/IFAS)

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GAINESVILLE, Fla. — A toxin produced by freshwater algae has garnered plenty of media coverage in recent years, but a new University of Florida study shows there’s little cause for concern about its presence in Florida lakes.

Researchers analyzed water taken from 187 lakes in 38 counties during a one-year period, and found that almost three-quarters of the samples had no detectable levels of the chemical microcystin. Only 7 percent of the samples exceeded the World Health Organization guidelines for drinking water, which is one microgram of microcystin per liter.

The results should reassure swimmers, boaters and anglers, said Dan Canfield, a professor with UF’s Institute of Food and Agricultural Sciences and an author of the study, published in the current issue of Lake and Reservoir Management.

“On a population basis for the state, it’s not a big issue,” Canfield said. “But if it’s a concern to you as an individual you can get a test kit for about $20 and use it to make a decision.”

The test kits, available online, are not as accurate as laboratory tests, but provide immediate results, he said. People with impaired immune systems or hypersensitivity to microcystin may want to exercise caution about lake use.

The chemical is produced by some blue-green algae species; it can damage the liver and has been implicated in human and animal illnesses.

In the study, the highest microcystin levels were found in lakes with the most abundant algae growth. A few samples from Lake Jessup in Seminole County and Lake Hunter in Polk County exceeded the WHO guidelines for recreational waters, 20 micrograms of microcystin per liter.

Microcystin levels can vary from one day to another, and from one part of a lake to another, said Dana Bigham, a UF graduate student and an author of the study. For these reasons, each lake was sampled six times during 2006, at two-month intervals, and water was taken from multiple locations.

Because the chemical is associated with algae blooms, lake users should avoid contact with large mats of floating algae, Bigham said.

The primary danger would come from swallowing water containing microcystin, she said. Research indicates that the effects of microcystin vary between individuals, depending on their sensitivity and the amount ingested. Exposure to the toxin can cause symptoms ranging from upset stomach to severe liver damage.

Microcystin was identified in the early 1980s, Bigham said. Scientists have determined that numerous blue-green algae species can produce it, though its cause is unknown.

The chemical has received media attention, particularly in the Midwest, where it’s associated with summer algae blooms. In Florida, the chemical can be produced virtually year-round, she said. The study indicated the highest microcystin levels occurred in September through December.

Contacts

Writer: Tom Nordlie, 352-273-3567, tnordlie@ufl.edu  

Sources: Dana Bigham, 352-273-3653, dlbigham@ufl.edu

Dan Canfield, 352-273-3620, decan@ufl.edu

Photo cutline

In this photo released by the University of Florida’s Institute of Food and Agricultural Sciences, graduate student Dana Bigham demonstrates water sampling at Lake Alice on the UF campus — Thursday, Sept. 17, 2009. Bigham is part of a research team that checked almost 200 Florida lakes for microcystin, a toxin produced by some algae species. Almost three-quarters of the samples showed no detectable microcystin. (AP photo/University of Florida/IFAS/Tyler Jones)

Caption at bottom. Click here for high resolution image

Multimedia available: http://news.ufl.edu/2009/09/17/eden-multimedia/

GAINESVILLE, Fla. — When scientists discuss Everglades restoration, one phrase pops up again and again — “getting the water right.”

It refers to the importance of water depth — making sure the proper areas are dry or marshy or submerged. For decades, experts had to take their own water-depth measurements or get data from multiple agencies.

In March 2005, things got easier. A modeling system called the Everglades Depth Estimation Network, or EDEN, went online. Developed by the U.S. Geological Survey working with the University of Florida and Florida Atlantic University, the system provides daily estimates of water depth and other information for most of the Everglades.

Now, a UF study verifies that EDEN’s estimates are accurate.

As reported in the current issue of Ecohydrology, researchers with UF, FAU, the University of Connecticut and the South Florida Natural Resources Center took water-depth measurements at 24 locations and compared them with EDEN’s estimates. Most estimates matched the measurements within 2 inches.

Frank Mazzotti, an associate professor with UF’s Institute of Food and Agricultural Sciences, says now that the system has been verified, he hopes it will gain popularity with scientists who assess the progress of Everglades restoration efforts, which aim to restore natural water flow throughout the region and support populations of indigenous animals and plants.

“We’ve never had a tool like this,” said Mazzotti, one of the study authors. “The idea is to make it freely available.”

Already, experts with UF and other Florida institutions have used EDEN to investigate populations of wading birds, invasive plants, fish and amphibians.

The system uses more than 200 monitoring stations throughout the Everglades that measure water depth. That information, along with geographic data, is then interpreted by computer software. The system generates water-depth estimates for the entire freshwater portion of the greater Everglades, broken down into quadrants measuring about 1,300 feet by 1,300 feet.

Mazzotti says he’s thrilled to have EDEN available, and is using it in a study that correlates alligators’ body condition with water levels.

The system will receive upgrades in the near future to provide better modeling of topography below the water and better water surface estimates, said Pamela Telis, project team leader for the U.S. Geological Survey.

The system is the brainchild of Aaron Higer, a longtime USGS program manager and current UF employee, who first envisioned the idea in the 1960s.

The system is found at http://sofia.usgs.gov/eden/.

Contacts

Writer: Tom Nordlie, 352-392-2411, ext. 282, tnordlie@ufl.edu

Sources: Frank Mazzotti, 954-577-6338, fjma@ufl.edu
Pamela Telis, 904-232-2602, patelis@usgs.gov

Caption: In this photo released by the University of Florida’s Institute of Food and Agricultural Sciences, spatial ecologist Ikuko Fujisaki visits one of the more than 200 monitoring stations used in the Everglades Depth Information Network, or EDEN - Thursday, Sept. 10, 2009. The stations provide information that is available to scientists online, to aid research on organisms in the Everglades and the progress of restoration efforts. Fujisaki, with UF’s Fort Lauderdale Research and Education Center, was part of the project team that developed EDEN. (University of Florida/IFAS/Tyler Jones)