ngin - Norfolk Genetic Information Network

19 March 2002


Pollination questions blowin' in the wind
High-tech growers say they'll take precautions, but foes are worried about contamination.
Des Moines Register Agribusiness Writer

Behind the promise of high-tech corn designed to yield pharmaceutical and industrial products lies a concern that pollen from the genetically engineered crop could drift to nearby fields and contaminate other crops.

"In any of these kinds of products, containment is always an issue," said Stephen Howell, director of the Plant Sciences Institute at Iowa State University in Ames.

Pollen drift two years ago was instrumental in spreading StarLink, a corn approved for animal but not human consumption. Massive recalls of corn-based food products and a drop in export sales resulted after it was discovered that StarLink had gotten into the human food chain.

Much of the StarLink problem resulted from poor handling of the actual crop, but experts also believe that pollen drift spread the corn beyond the fields where it was intentionally planted.

Scientists now worry that a similar situation with the new generation of pharmaceutical and industrial crops could have even more damaging results for corn sales and exports. Proponents say the so-called gene flow resulting from pollen drift can be controlled.

This spring, farmers throughout the Midwest will plant test plots of the new wave of so-called designer corn. One transgenic corn-protein product - trypsin, an industrial enzyme used to produce pharmaceuticals - will be grown commercially this year on hundreds of acres throughout the U.S. Corn Belt.

"This is not a StarLink," said Zivko Nikolov, vice president of process development and production for ProdiGene Inc., which developed the corn-based product.

"There was no control" in StarLink production, he said. By contrast, ProdiGene will "control every single step."

ProdiGene is a Texas biotech company, spun off from Pioneer Hi-Bred International Inc., that is being wooed by Iowans who want to build a processing plant in Ames that would extract protein from the new generation of high-tech corn.

Nikolov said ProdiGene has devised a step-by-step monitoring system for production of specialty corns. This year, the system will be employed as the company commercializes its trypsin-bearing corn.

Bill Horan, a Knierim farmer in the vanguard of so-called pharming, insists pollen from the new specialty corns can be contained.

He and his brother, Joe, grew "pharma" corn last year for a French biotech company, also being courted for the Ames project.

Like ProdiGene, the Horans worked closely with federal regulators to develop a system intended to prevent pollen drift, in cases employing methods that exceeded regulators" requirements.

Pollen drift can be cut by using physical barriers or biological barriers, preferably both, said Iowa State's Howell, who is a leader in the bid to build the $50 million protein extraction plant in Ames to process the specialty corn.

The Horans, for instance, use wide buffer areas around their fields. They also grow male sterile corn plants alongside rows of nontransgenic, commercial corn, which provides the pollen to fertilize the "pharma" corn. As added precautions, they detassel the corn, use farm equipment in those fields that is not used in fields of regular corn, and document closely every stage of production.

"This corn that we're producing goes nowhere near commodity channels," Bill Horan said.

"We are accountable for every step of the way. We're on the line for this."

Despite such assurances, skeptics persist. Their fears stem in part from corn's ability to pump out large amounts of pollen, coupled with the fact that it is the crop of choice for producing plant-based pharmaceutical and industrial products.

Corn plants are "basically just broadcasting piles of pollen out into the air and hoping it lands where it's needed," said John Nason, an assistant professor of botany at Iowa State who has studied gene flow.

With the growing season just around the corner, environmentalists, organic growers and even some proponents of the new class of engineered crops worry that drifting pollen could cause contamination.

They fear that grain intended for use in cereals, chips and dozens of other foods would end up containing ingredients for industrial products, or worse, pharmaceuticals. They also worry that pollen drift would contaminate so-called commodity corn destined for export, closing major foreign markets to U.S. grain.

They cite the StarLink experience. Planted on less than 1 percent of U.S. acreage in 2000, the grain was found in 10 percent of the crop harvested that year.

StarLink pollen, carried by the wind, insects, birds or other animals, contaminated fields of conventional corn. Pollen drift didn't cause the StarLink problem, but it compounded it, experts say.

If pollen from the emerging class of biotech-based corn were to cause similar contamination, the results would be catastrophic, particularly for Iowa. The state produces about one-fifth of all U.S. corn.

"We cannot afford to jeopardize our commodity grain," said Larry Johnson, head of Iowa State's Center for Crops Utilization Research.

Concern about pollen drift appears to be growing.

* The Iowa Farm Bureau Federation has called for a formal review of regulations governing both field testing and commercial production of the high-tech crops.

* Several Midwestern states are collaborating on a study of pollen drift.

* The National Academy of Sciences has recommended closer regulatory scrutiny.

* A coalition of environmental and consumer groups - Genetically Engineered Food Alert - plans to call for a halt to open-field testing of the new class of transgenic crops to prevent contamination. The coalition contends too much is at stake to permit the production as long as field-to-field gene flow is a possibility.

Repercussions would be serious if pollen from the new class of corn contaminated other cross-pollinating plants.

Also at risk are the hopes of farm states seeking to capture the economic benefits of the breakthrough biotech-based crops. Iowa is positioning itself to capitalize on the crops" potential, and proponents are trying to lure public and private investment in the proposed protein extraction facility in Ames.

A perceived pollen drift problem could jeopardize those plans.

Farmers growing StarLink were to have surrounded fields with 660-foot buffer zones.

"I"m not a scientist, but I grew up on the plains of Minnesota where it's very windy," said David Moeller, a St. Paul attorney and expert in legal issues linked to transgenic crops, including pollen drift contamination. "Whether that was adequate or not is an open question."

"I don't want this shot down because people haven't thought about it. Let's solve this issue," Iowa State researcher Johnson said. "Another StarLink problem could have devastating effects."

See POLLEN, Page 3D

Corn uses grow

Corn designed to yield ingredients for industrial and consumer products, including pharmaceuticals, promises to transform agriculture and other industries.

* Drug manufacturers will shift raw material production from factories to fields.

* Industrial enzymes used in food and pharmaceutical production will be derived from corn instead of swine or bovine tissue.

* Solvents, lubricants, fuels and plastics previously made from petroleum also will come from the tall, green crop that each summer covers more than 12 million acres of Iowa farmground.

Some products already are on the market; dozens more are on the cusp of commercialization.

Pollination basics

Plants are pollinated in various ways.

* Soybeans self-pollinate, producing little pollen, compared to corn. Crops such as alfalfa and fruit-bearing trees rely on insects for pollination.

* Corn is a cross-pollinating crop that relies largely on the wind and gravity to carry pollen from tassels atop the plant onto silks below. Pollen forms a tube, carrying genetic material through the silks to the corn cob where kernels are formed.

* Wind pollination is random, requiring more pollen to accomplish fertilization. By some estimates, corn pollen can drift a long distance from the plant that produced it, resulting in contamination.

Worries grow over corn contamination

Register Agribusiness Writer

Pollen drift, a source of StarLink corn's contamination of the food chain two years ago, has resurfaced as an issue for biotech-based crops.

With spring planting just around the corner, concerns are mounting that corn designed to produce ingredients for industrial and pharmaceutical products could contaminate crops destined for the food chain.

Proponents contend corn pollen can be contained, but even they admit there are no guarantees.

What's more, gene flow from pollen drift is just part of the problem.

As happened with StarLink, contamination also can come from:

* Seeds for specialty crops inadvertently mixed with conventional corn.

* Kernels of so-called designer corn that end up in loads of conventional grain through lapses in harvesting, handling or storage.

* "Volunteer corn" grown from kernels left in a field after harvest.

Another possibility that has assumed added urgency since Sept. 11 is the intentional introduction of so-called pharma seed or crops into grain intended for food use.

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