© World Food Program / Richard Lee
Is plant breeding really so essential, or is this just the whining of Luddite researchers who fear change, even beneficial change? We asked some folks who know the field, but also have roots in genetic engineering, and they affirmed that genetic engineers would be stymied without conventional breeding.
Joel Cohen, a visiting researcher at the International Food Policy Research Institute, told us,. "It's absolutely key that you are able to do it. There's no way any biotech crop can be released without being made stable and useful with conventional plant breeding technology. ...Not just so it expresses the gene well, but so it does so in a genetic context that makes the whole crop viable."
We heard much the same song from Ronald Phillips, a professor of plant genetics and director of the Center for Microbial and Plant Genomics at the University of Minnesota. "I'm very supportive of traditional, conventional methods, they're tried and proven."
So far, we've used "conventional breeding" to mean the opposite of "genetic engineering." But the two fields are merging somewhat, says Phillips, who has worked in both. Genetic engineering, he says, is "an enhancement" of the ability to move genes pioneered by conventional breeders. "It has the potential to bring in genes that are unique and to speed up the development of new varieties."
Straining with strains
Here's his point. Say a strain of native-cultivated corn from Peru resists a viral disease, but is poorly suited to commercial production. A conventional breeder who wanted to use that gene would cross it with a high-yielding variety. But half the genes in the first generation -- including many for unwanted characteristics like small kernels -- would come from the Peruvian strain.
And from there, many years of work would be required, says Phillips, "to recover all the good features, plus the one you're interested in moving." The result is that breeders may simply shun the troublesome but promising Peruvian strain.
But the techniques of genetic engineering, Phillips says, "should allow us to move a gene, or a set of genes, without having to move the whole set." And if the transfer occurred within the species, the crop might encounter less public resistance than today's GM crops.
Urge to merge
However, a recent CIMMYT study of marker-assisted selection concluded that, "for many practical applications the economics ... are still being worked out on a case-by-case basis." If the desired traits are obvious early on, the study concluded, markers might simply raise costs and complexity over conventional breeding.
Coors, a corn breeder who specializes in the use of the whole plant for silage, wonders about the increased food production that was supposed to come from genetic engineering. He notes that the peak in global per-capita grain production occurred when genetic engineering began siphoning talent from traditional breeding programs. It could be a coincidence, he admits, but it may be worth exploring, since per-capita grain production is probably the single most important data point in predicting our future ability to feed ourselves.
But is it too soon to judge genetic engineering by this exacting standard? GM foods are new, and are encountering widespread resistance, both in Europe, and, as the present standoff in Zambia indicates, far beyond.
Another piece of the explanation comes from commercial decisions by Monsanto and the other firms that ushered the transformed seeds to market. They chose traits they thought would interest U.S. farmers, not international ones. To date, virtually all GM seeds sold in the United States have the ability either to resist herbicides or make their own pesticides. These are not traits that will improve nutrition or necessarily grow more food.
Cottoning to GM crops
He points to the Chinese experience with transgenic cotton (although it's not a food crop, it's one of the few GM crops being widely planted overseas). GM cotton, transformed to kill insects, is booming in China, even on farms smaller than one hectare in area. "Response by China's poor farmers to the introduction of Bt [Bacillus thuringiensis, a natural pesticide] cotton eliminates any doubt that GM crops can play a role in poor countries," wrote the authors of a new survey (see "Plant Biotechnology in China" in the bibliography).
Plantings soared from 2,000 hectares in 1997 to 700,000 hectares in 2000, equal to 20 percent of the national cotton crop. Although the GM crops required only 19 percent as much pesticide, reducing costs by $762 per hectare, they slightly outyielded conventional crops. Five percent of farmers using the transformed cotton - compared to 22 percent of farmers growing the conventional cotton - reported health symptoms characteristic of pesticide poisoning.
To Cohen, this shows the potential of genetic engineering for third-world agriculture. "You are seeing positive benefits. We are making farming safer, more economic for producers and containing the cost for urban people."
At this point, he says, it's premature to argue about impacts on food production, but thinks biotechnology has potential to "provide food in a safer, better manner."
Still, Cohen, like all the other experts we spoke to, insists that plant breeders play a central role no matter how the genes are moved around. "It's amazing how little understanding there is. People don't appreciate what it takes to get a variety out, that single individuals have contributed varieties that have been out there for decades, and what a great accomplishment this is. We need to maintain a breeding capacity: diseases change, insects change, drought problems arise, and if we have no capacity for breeding, we have no defense."
© David Tenenbaum
A prop for property?
Nowadays, especially after a December, 2001 decision by the U.S. Supreme Court, "All crops and species are basically fair game for this," says Tracy. Buyers of Monsanto's GM corn, soybean and cotton, for example, cannot save seeds, and breeders cannot remove genes.
All this is a departure, says Tracy. "Plant variety protection ... allowed farmers to save seed, as has been happening for millennia, and allowed the new variety to be used for plant breeding." These provisions were significant - and wise, Tracy says. "That form of protection was developed by plant breeders, and they wanted to make the genes available to everyone."
Many plant breeders worry that the interest in genetic engineering, and the shift in power away from farmers, universities, and plant breeders, are making it tougher to pursue the technology that has enabled people to feed themselves since the dawn of civilization.
"I view it as a food security issue," says Tracy. "Where are the genes, the germplasm for future crop improvement? Who owns the genes and who has access to them? Traditionally, the public sector controlled them, and in general plant breeding was done for the public good."
As interest among funders and students alike has shifted toward genetic engineering, so has power. Today, says Tracy, "for many important species, the elite genetic material is controlled by private companies, and their goals are frequently not the same goals as our goals."
©2002, University of Wisconsin, Board of Regents.