Renee Lafitte walked recently through a field of sickly looking corn. "You can see how the leaves are starting to burn," she said, pointing to a stalk where the long green leaves were tipped with brown. "One of the things we're looking for and thinking about going forward is what we anticipate about climate change. We expect things to get worse."
Lafitte is a research fellow with Pioneer Hybrid, the giant seed division owned by DuPont. In this plot of land in Woodland, Calif., she is testing 200 new experimental traits that could help corn survive drought. Genetic improvements are credited with saving the corn and soybean crops during last summer's historic dry spell. Yields ended up being much better than expected.
So-called GMO seeds are used in the vast majority of corn and soybeans grown in this country — crops used to feed livestock which end up at the grocery store meat counter.
But the debate over the effects of tinkering with Mother Nature at a genetic level hasn't gone away in the 17 years since the first seeds were approved for commercial use. While efforts to label foods containing GMO products failed in California last fall, other states have taken up the issue. Anti-GMO activists have organized marches against seed giant Monsanto, and after unapproved Monsanto GMO wheat showed up on a farm in Oregon years after trials had been discontinued, wheat exports were suspended and farmers started filing lawsuits. (How the wheat got there is still being investigated, but Monsanto calls the circumstances "suspicious.")
"We have not done a very good job of talking about GMOs and how our food is grown," said Cathleen Enright of the Biotechnology Industry Organization, a group representing the major agricultural seed and chemical companies.
Scientists working on plant genetics are beginning to step away from their microscopes and speak out.
"It's time for a new, fresh conversation around the balancing act between the demand for food and the tools and technologies we use to meet that demand," said Robb Fraley, chief technology officer for Monsanto.
Seeds are a $10 billion business for Monsanto, and Fraley just won the World Food Prize for his pioneering work in creating the first soybean modified to withstand the pesticide RoundUp. RoundUp Ready soybeans dominate the market, and China just approved the use of Monsanto's latest version.
"We still kind of talk about this like it's brand new science," Fraley said. "The reality of it is these products have been used in the marketplace for almost 20 years. They have a complete track record of safety that's been affirmed by experience."
Not all genetic altering is the same. Some involves using a plant's own material, while some involves inserting DNA from a different plant, or even from an animal or microorganism. At a Syngenta lab in North Carolina, scientists are testing new modifications in corn, soybeans and sugar cane.
One new product that protects corn from root worm, the crop's top pest, is finally coming to market after 14 years of testing and regulatory hurdles. Agrisure Duracade puts DNA from soil bacteria into the roots of corn stalks to kill root worm. At the same time, the company is also developing a drought-tolerant strain of corn akin to traditional hybrid breeding.
"It is not a GM crop so much," said Michiel Van Lookeren Campagne, Syngenta's head of biotechnology. "We need to feed nine billion people on this world. We need to do this on less land."
GMO seeds may be good for the environment—using less land, less water, fewer pesticides—but are they safe for people?
"There is still not a single documented case of harm to any human or animal consumption," said Professor Alan McHughen, a plant geneticist at the University of California Riverside. He said a recent report indicating GMOs may lead to cancer in rats has been discredited by the scientific community.
"I encourage people to be skeptical, but these companies don't have to assure consumers that these products are safe," he said. "We have safety assessments coming from FDA, USDA, EPA, the National Academy of Sciences, the American Medical Association, the American Association for the Advancement of Science and every other professional medical and scientific society worldwide that said categorically these products are as safe as products of conventional plant breeding."
California farmer Ken Oneta grows GMO corn next to his conventionally grown tomatoes. "We still have to spray," he said, "but instead of using chemicals that were a little bit harsher on the environment, harsher on our people, we're able to use softer materials and safer stuff."
Oneta sells much of his corn to local dairy farmers, and if laws are passed forcing them to label their milk as including GMO products, they might stop buying his feed. "If this becomes unsellable, I'll probably have to go back" to conventional corn, he said.
"I, as a consumer, am much more worried about excessive use of pesticides, about excessive use of fresh water," said Pioneer's Renee Lafitte. "Those, to me, are greater environmental concerns and even health concerns around agriculture than are GMOs."
As weeds and pests evolve to become resistant to GMO seeds, Lafitte bemoans the lack of competition in the industry.
"When only very large companies can afford to go through the regulatory costs," she said. "That limits the options they can put on the table. So where is the next technology coming from? We know insect evolution and weed resistances will continue to happen. It's a part of biology."
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