How To Fight Super Pests? Build Superbugs
William Pentland
Forbes, 18 November 2008

*USDA paves way for growing predators in the lab to fight threats to agriculture.

The Asian Citrix Psyllid is a brown insect that spreads the most devastating citrus disease in the world. Just ask Florida's orange growing industry.

A native of the border regions of Pakistan and India, the parasite, which infects citrus plants with a so-called "greening disease," probably appeared by accident in the southeastern U.S. less than a decade ago. The bug has no natural enemies in its new home and requires far deadlier pesticides to kill it than other insects do. As a result, they've infested much of Florida and decimated the state's orange juice industry.

Until now, growers poured on pesticides and hoped for the best. But now a controversial solution may be at hand: creating predators in the lab.

In October, the U.S. Department of Agriculture's Animal and Plant Health Inspection Service, one of three federal agencies responsible for oversight of genetically modified organisms, said it would soon give the green light for transgenic insects designed to combat the spread of invasive species like the Asian Citrix Psyllid.

The agency released a draft regulation, the most comprehensive overhaul of genetically modified organism (GMO) regulations since 1987, to "respond to emerging trends in biotechnology." It provides the vague parameters that applicants must meet to commercialize genetically engineered (GE) bio-control organisms.

Though it's likely to change before becoming law, the proposal puts in place new permitting procedures for the interstate movement and environmental release of non-vertebrae transgenic animals, promising to usher in a new era. "There are relatively few examples today of genetically engineered biological control organisms, but these may become more common in the future," according to the report.

More than 6,500 invasive species have established themselves in the U.S., disrupting natural habitats, decimating the population of many native species and wreaking havoc on the economy. By at least one estimate, invasive species cost the U.S. roughly $130 billion in losses annually. Mark Hoddle, a professor of entomology at the University of California, Riverside, says the GE insects promise to be a safe, effective way of halting the problem.

"Almost all biological control processes use natural enemies that are highly screened for post-specificity, meaning they feed exclusively on the pests you want to eradicate," says Hoddle. "Genetic engineering allows you to enhance this trait significantly so that the engineered insects eat the desired species and then starve themselves to death."

Bill Freese, a science policy adviser at the Center for Food Safety, a Washington D.C.-based nonprofit, isn't convinced. "The stringency of the rules needs to be much higher than the vague, unclear standards in the [Department of Agriculture] regulation," he says. "This is all experimental stuff and there is a high risk of unintended consequences."

One victim, ironically, could be the booming market for pesticides and herbicides, though many companies like Monsanto and Cargill that developed the pesticides are best positioned to develop the engineered bugs that will replace them.

There is no shortage of applications for using this brand of biological control, especially if regulators ramp up restrictions on pesticide and herbicide as many believe they will in order to protect water supplies and combat a number of environmental problems linked with overuse of pesticides.

In Florida, some citrus growers may shut down operations until they find a more effective way of eradicating the pests. Others have simply poured on heavier and heavier concentrations of chemicals.

Florida's orange growers aren't the only farmers facing pest problems that didn't exist a few years ago. California has waged a decade-long war against the Glassy-Winged Sharpshooter, a half-inch long brown fly, which infects grapes with a rotting disease that has cost the state's wine-growers millions of dollars in losses. Then there's Kudzu sweeping across the American south, along with a host of other threats.

"Everything has a risk, but these risks can be quantified," says Hoddle. "And in many cases, the risk is one most people would accept given the costs of doing nothing."