Issue Date: January 12, 2004
BIOTECH WHEAT'S INTENSE DEBATE
In December 2002, Monsanto petitioned the U.S. Department of Agriculture to allow commercialized production of its herbicide-tolerant, genetically engineered wheat variety--Roundup Ready spring wheat. Although USDA has not said Monsanto can go ahead with its product, the petition alone has sparked an intense debate among growers, food processors, agronomists, and environmental activists.
Wheat is the first major genetically engineered food crop to be commercialized. The other important biotech crops--cotton, corn, and soybeans--are used primarily for fiber or animal feed. For this reason, the prospect of biotech wheat has been subjected to a great deal of scrutiny.
Some wheat farmers fear that if Roundup Ready wheat is commercialized, significant export markets will be lost. Several wheat-importing countries say they will not buy any U.S. wheat if biotech varieties are grown. At least 37 countries require labeling of crops that have detectable transgenic content above certain thresholds. USDA estimates that the cost of establishing a dual-marketing system for wheat would be about 70 cents per bushel, which would make biotech wheat less competitive in global markets.
Large food processors, such as Kraft Foods, worry that if Roundup Ready wheat is approved in the U.S. but not in the European Union (EU), the company may have to produce separate lines of wheat products--one kind of Oreo cookies made with biotech wheat and another made with conventional wheat, for example.
When wheat fields are planted with a different crop the following year, volunteer wheat is a major weed, and Roundup (glyphosate) is usually used to kill it. Carol Mallory-Smith, professor of weed science at Oregon State University, is concerned that volunteer Roundup Ready wheat would be a particularly troublesome weed to eradicate because it can't be killed with glyphosate, a broad-spectrum cheap herbicide that is widely used on fields where conservation tillage--planting without plowing--is practiced.
To discuss these issues, the Washington, D.C.-based Center for Science in the Public Interest convened a forum in mid-December. Interestingly, there was general agreement among the speakers that Roundup Ready wheat will be safe to eat. There was also consensus that other varieties of biotech wheat now under development, such as allergen-free wheat, could eventually offer benefits to consumers. The concerns raised were mostly about the effects of biotech wheat on export markets, on food processors, on farm income, and on how the biotech wheat would affect the weeds and diseases that farmers must contend with.
IN THE U.S., wheat is the third largest crop, with an annual value of about $6 billion. The U.S. is the world's largest wheat exporter, selling about half its production abroad. However, wheat growers already face stiff competition from Canada, the EU, Australia, and Argentina. "U.S. farmers have suffered a declining global market share for nearly 20 years," said Michael Rodemeyer, executive director of the Pew Initiative on Food & Biotechnology.
"Biotechnology may well offer a way to increase production efficiency to help make U.S. farmers more cost competitive," Rodemeyer said. "But given the global controversy over genetically engineered foods, biotechnology presents market risks for wheat growers as well," he said. Many countries that now import U.S. wheat may decide not to accept any out of fear that it may contain low levels of transgenic wheat, he warned.
Gary R. Blumenthal, president of World Perspectives, a global food and agriculture market analysis consulting firm, noted that U.S. wheat exports have fallen 50% in the past 20 years, and if that trend continues, the U.S. may become a net importer of wheat within 10 years. He noted that the wheat industry is making investments that will allow it to segregate biotech wheat from conventional varieties. Already, exporters have developed a way to segregate higher value products, such as food-grade soybeans going to Japan, he said.
Jerry Steiner, Monsanto's executive vice president for commercial acceptance, said Roundup Ready technology has significantly increased farmers' profitability "by giving them a simpler and better weed control system than otherwise was available." He also claimed the technology has reduced the amount of herbicides used on crops.
In addition, Steiner said, Roundup Ready technology has increased the acreage devoted to conservation tillage. This allows the stubble from the previous year's crop to be left in the field, reducing erosion and providing wildlife habitat, he observed. Field trials show that yields can be increased 5 to 15% with Roundup Ready wheat, he said.
Monsanto has pledged not to commercialize Roundup Ready wheat until it identifies buyers and until grain segregation systems are in place to separate biotech wheat from conventional varieties, Steiner said. It won't be trying to sell the wheat until regulatory authorities have accepted it in both the U.S. and Canada. The company is working on many varieties of biotech wheat, such as drought-tolerant wheat, that could be very useful to farmers and consumers, he said.
Ronald J. Triani, senior director of scientific relations for Kraft Foods of North America, warned developers of biotech crops "to make sure that the benefits you are thinking about when you are creating crops for agriculture are benefits that are going to be perceived positively by our consumers. Biotech wheat with real [consumer] benefits would go a long way toward ensuring market success," he said. Kraft has not yet decided whether to use biotech wheat after it is approved, he said.
Gregory Jaffe, director of the project on biotechnology at the Center for Science in the Public Interest, noted that the "U.S. does not have a mandatory preapproval process for biotech crops. Consumers are going to look at wheat differently, and they are going to want to be extra certain that that wheat is safe," he said. Some in the food industry have said that the Food & Drug Administration's approval process for genetically engineered foods isn't sufficient, he observed. Consumers also want to see that Roundup Ready wheat is safe for the environment, he said.
Mallory-Smith raised another issue. She noted that genes from Roundup Ready wheat can move into weeds. In many situations, transfer of genes from biotech crops to weeds does not create problems, she explained. But transfer of the gene for Roundup resistance to weeds could be troublesome because "we use Roundup in so many other areas besides production fields," she said.
Even without gene transfer, increased use of Roundup will select for Roundup-resistant weeds, just as, over time, DDT use increases populations of DDT-resistant insects, Mallory-Smith said. As a consequence, another herbicide will eventually have to be used on Roundup Ready wheat. So the question becomes: "Do you actually increase herbicide use once you create herbicide-resistant weeds?" she asked.
W. Daren Coppock, chief executive officer of the National Association of Wheat Growers, pointed out that a biotech variety could be the greatest product in the world, but if the customer doesn't buy it, "it is not worth anything to us or to the people who make products from it.
"Varieties in wheat last about seven years before disease complexes and insects catch up with them," he said. Biotechnology is an important tool in creating new varieties that will be less vulnerable to diseases and insects, he added.
Scientists not present at the forum have also voiced concerns about the use of Roundup Ready wheat. One concern is that if glyphosate is used extensively on wheat, it may raise the levels of Fusarium fungi in the soil. There is clear evidence that levels of this fungi have increased on fields where Roundup Ready soybeans and canola are grown, says Charles M. Benbrook, an agriculture consultant in Sandpoint, Idaho, who was formerly director of the National Academy of Sciences' Board on Agriculture. Where Roundup Ready soybeans are grown, the levels of the fungus always spike and build up over time, he explains. Increasing Fusarium levels in the soil could make the fungus--the number one disease problem in wheat--even more prevalent, he says.
ANOTHER CONCERN, Benbrook observes, is that glyphosate, which in the past has not shown up in groundwater, may do so if it is used even more extensively. In some areas of Denmark and France, where large amounts of glyphosate have been used, it has altered the soil microbial community, leading to a change in glyphosate's metabolic breakdown pathway, he explains. There, glyphosate degrades to a stable metabolite that is detected in groundwater. To avoid this problem, Denmark has phased out most agricultural uses of glyphosate. (Monsanto disputes these claims, saying glyphosate has not been detected at levels above the drinking water threshold.)
Benbrook agrees with Mallory-Smith that commercialization of Roundup Ready wheat may eventually lead to increased use of herbicides on wheat. Using USDA data, Benbrook analyzed pesticide use on corn, soybeans, and cotton during the first three years of biotech commercialization--1996–98--and for the years 2001–03. During the earlier period, total pesticide use in biotech corn, soy, and cotton was 25 million lb less than in conventional varieties. But in the 2001–03 period, total pesticide use was 73 million lb more than it would have been if no biotech crops had been grown. Altogether, some 550 million acres were planted with genetically engineered crops from 1996 to 2003. Biotech cotton and corn still require less pesticide per acre than conventional cotton, but genetically engineered corn and soy require more, Benbrook says. The primary reason for the increase in pesticide use is that weeds have become resistant to glyphosate, he explains.
In the face of these issues, wheat growers and major processors have not yet decided whether to grow Roundup Ready wheat or purchase it once it is approved. A sister organization, the American Soybean Association, effectively killed at least two varieties of transgenic soybeans that were approved in the U.S. because they were not approved in Europe. It advised its members not to grow the crops, out of fears that export markets for U.S. soybeans would be hurt. Coppock said the decision has not been made whether to try to foster or kill Roundup Ready wheat once it is approved.
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