UF Licenses New Mole Cricket Control To Biotech Firm

December 8, 2000

GAINESVILLE, Fla. — A tiny parasite imported from South America by University of Florida researchers will soon be available commercially to end a 30-year battle with mole crickets, one of the most troublesome agricultural pests in the Southeast.

Field tests show that the parasite — a worm-like organism known as the mole cricket nematode — will survive in the region’s climate and kill mole crickets on a long-term basis, said Grover Smart, professor of nematology with UF’s Institute of Food and Agricultural Sciences. The patented organism, expected to be available by fall 2001, will help farmers, home owners and golf course managers combat the pest.

The mole cricket, which causes about $94 million in damage to Florida turf and pastures each year, also affects ornamentals and other crops, he said. Damage to grasses and seedlings is caused by the insects feeding on roots and loosening the soil.

Smart said UF experiments with the parasite in North Florida already have caused a decline in local mole cricket populations.

“We just don’t see a lot of mole crickets any more in areas where we have tested the parasite,” Smart said. “As the nematode spreads, it provides highly effective mole cricket control or at least reduces damage to a level that is acceptable from an economic standpoint.”

Accidentally introduced to the United States from South America more than 75 years ago, mole crickets first became a nuisance to Florida vegetable growers in the 1930s, but were successfully controlled with arsenic baits and pesticides such as DDT. The pest became a serious problem in the 1970s when environmental concerns led to federal restrictions on DDT-type pesticides. Since then, other pesticides have been used with limited success, Smart said.

UF researchers first identified the mole cricket nematode in Brazil during the early 1980s. Smart then isolated a strain of the nematode to achieve almost 100 percent effectiveness against mole crickets in laboratory experiments with little or no threat to other U.S. insects. In 1990 he and UF nematologist K.B. Nguyen identified the nematode as a unique species, Steinernema scapterisci. UF holds three patents on use of the nematode for pest control.

Once the parasitic nematode enters the body of a mole cricket to mature and reproduce, it kills the cricket within 48 hours. Young nematodes emerge from the dead cricket about a week later to seek new hosts. Once infected, mole crickets can spread the nematode to new areas by flying, crawling or burrowing, Smart said.

“The mole cricket nematode is a good example of biological control, using natural predators to control pests without heavy reliance on chemical pesticides,” Smart said. “Other mole cricket predators live above ground, but our nematode dwells in the soil where mole crickets do most of their damage — that’s the real advantage of this parasite.”

MicroBio, a biotech firm owned by Becker Underwood, Inc. in Ames, Iowa, has obtained exclusive rights through UF’s Office of Technology Licensing to use the nematode in a commercial product. In late 2001, the company will market the organism under the Nematac S product name, said Graeme Gowling, MicroBio general manager.

The product will be marketed to turfgrass and sod farmers as well as home gardeners. Golf courses are expected to be major users, he said.

Gowling said MicroBio, the world’s largest commercial nematode producer, is working with a statewide mole cricket task force to help protect millions of acres of cattle pastureland in Florida. However, some ranchers are concerned about the product’s cost, which could be as high as $200 per acre.

“Ranchers who are operating under a tight economic situation just cannot afford to spend that much on mole cricket control,” said Herb Harbin, chairman of the agricultural research and education committee of the Florida Cattlemen’s Association in Kissimmee. “But we need something to control this pest — the mole cricket problem has been really bad in the last 10 to 15 years. Literally hundreds of thousands of acres of bahia grass pasture have been totally destroyed.”

Martin Adjei, assistant professor of agronomy at UF’s Range Cattle Research and Education Center in Ona, said cattle farmers could reduce costs by “strip treating” pastureland, applying the parasite to selected areas while leaving adjacent areas untreated.

“Our research shows that the mole crickets will spread the nematode around once a large number of them are infected,” Adjei said. “Now we want to determine how far apart the treated strips should be for effective control of the pest. For example, if we can reduce the treatment to one-eighth of the total area and let the nematodes spread, that may be a cost-effective way for cattle producers to use this product on millions of acres.”