BOSTON — Plant biologists have a message for crop pests. Their science is ready for takeoff in using genetic engineering to enhance crop plants' natural defenses. But the pests, in effect, have an answer. They developed biological resistance to cope with chemical pesticides. Now they can rely on human social resistance to genetic engineering to blunt the scientists' efforts.
What R. James Cook of the US Agricultural Research Service at Washington State University in Pullman calls "the current information explosion in the biological sciences" has brought pest management with genes, rather than chemicals, to a historic turning point. Plant breeders have used such management for a century. They developed pest-resistant crops by cross-breeding among related varieties or between a crop plant and wild relatives. This moved desirable genes into the crop plant. Now they can read the genetic blueprint for a plant's natural defenses directly in the plant's DNA. They now are learning how to manipulate the genetic instructions to make those defenses more formidable.
This is the new science of pest management using transgenes - that is, using transformed plant genes or even genes from unrelated species. It promises to extend the development of pest resistance as far beyond traditional breeding as modern breeding techniques have progressed beyond medieval agriculture.
Yet as Dr. Cook told a symposium during the meeting of the American Association for the Advancement of Science in Philadelphia in February, "[the] question of social acceptance of pest management with transgenes ... remains a deterrent to plant biotechnology...."
This seems irrational to many plant scientists. They cite statements by the National Academy of Sciences and by 11 scientific societies that insist there is no scientific difference between plants transformed by traditional methods and those transformed by transgene engineering. The issues of safety and acceptability should be decided on a plant by plant basis, not by the method that produced the new plant, these organizations say.
Nonscientists may not see it that way. As Sheldon Krimsky, environmental policy professor at Tufts University in Medford, Mass., recently pointed out, many people are uneasy about a vegetable that has received a fish gene to become more frost resistant. A plant's overall pest defenses can involve hundreds of genes. They deploy and control a highly complex system that botanists compare to a complicated series of password protected gates and subtle chemical countermeasures.
The public has reason to be suspicious of glib reassurances. Krimsky discussed US Department of Agriculture proposed guidelines that would allow food companies to call genetically engineered produce "organic" as long as growers used no chemical pesticides. This "clearly is not the way organic consumers view it," he says. He added that it can look as though "the USDA was trying to please a very aggressive agricultural industry."
Consider the development in USDA labs in Lubbock, Texas, of genetic techniques that prevent crops grown from commercial seed from producing viable seed themselves. As this technique is adopted industrially, it could mean that farmers would have to rely totally on seed companies. They couldn't grow their own seed. That would help seed companies protect patented varieties. But it would be especially tough on farmers in less developed countries who can't afford to buy new seed every year.
These examples feed public suspicions that the plant genetic engineers don't have the public good foremost in their thinking. The geneticists and their sponsors should treat advocates who represent public misgivings as partners rather than opponents.
Pest management is poised for major beneficial new developments. These will be needlessly delayed unless the geneticists and lay people are ready to walk into that promising future together.