Sunday, July 06, 2008

Seeds of discord, winds of change

kw: book reviews, nonfiction, biology, genetic engineering

Contrasting statements:
  1. From the Statement of Policy of the FDA, "Ultimately, it is the food producer who is responsible for assuring safety."
  2. From Monsanto's director of corporate communications, "Monsanto should not have to vouchsafe the safety of biotech food. Our interest is in selling as much of it as possible. Assuring its safety is the FDA's job."

Dr. Richard Strohman of U. Berkeley has written, "DNA is most definitely not the secret of life...the idea that there is a direct relationship between a single gene and a single trait is completely erroneous...[this is] the myth of genetic determinism."

This myth underlies the entire biotechnology industry today. In Uncertain Peril: Genetic Engineering and the Future of Seeds, Claire Hope Cummings chronicles how the misapplication of genetic ideas is undermining the foundation of the world's farming enterprises. Her charges against the biotech industry are as numerous as they are large. In whatever measure they are correct, they foretell a greater threat to the sustenance of civilization than any other effect of human activities.

Did you know that tomatoes and potatoes, being related and being members of the Nightshade family, are potentially quite poisonous? A large salad of tomato greens can stop your heart. Yet the fruit is nutritious and quite safe to eat! How can this be? The fact is, many, many plants produce various pesticides as they struggle to grow to maturity without being eaten down to the roots, yet their food parts contain no trace of these pesticides. So why are such critters as the Tomato Hornworm able to eat the leaves without harm? In the perpetual arms race that is evolution, this worm is one critter that has evolved a way to inactivate the Nightshade toxin in its food.

In the perpetual struggle of science to imitate nature, and it is hoped, do her one better, biotechnologists have sought to take potent natural pesticides such as the toxic proteins of B. thuringiensis and cause their expression in food plants. These plants then grow with less need for the application of chemical pesticides. Getting them to produce their own "BT toxin" has been seen as a simple matter of getting the right gene from the BT bacterium into the genome of the plant you want to grow. But there is a catch, a big one.

The scatter-shot methods being used to get novel genes into the genomes of crop plants seldom work, but when they do, they work too well. "BT corn" (BT maize), for example, expresses the BT toxin proteins in equal amounts in all its cells, even though the pests that BT affects mainly attack the roots, and the leaves a bit less. They don't attack the kernels much at all, leaving that to a different array of pests that aren't bothered by BT! The problem comes when we find that many people are harmed by BT residues.

Many farmers rely on sprays of BT organisms, the natural bacteria. These effectively kill pests, and the toxins can be washed right off the kernels after harvest. People can't avoid ingesting BT toxin if it was produced right inside the cells of the kernels.

So why haven't folks done the extra work to get the BT genes into a section of the genome that is "turned off" in the kernels? There is a nice, convenient stretch of DNA that contains the plant's natural pesticide-making genes, which are switched off in the seed cells.

Such precision of placement is quite out of the question with "modern" technology. Simply developing the methods that would allow it is prohibitively costly. Oh, it will get done anyway, but slowly, almost as a side effect of other studies. But this is only one instance, and in this case, the relevant target is pretty well known. For most plants, they'll also have to do more science to figure out exactly where to put new genes, to take advantage of such natural switching mechanisms.

All this digression is my own, an introduction to the troubles we are getting ourselves into by creating GMO's, Genetically Modified Organisms. And this is just one of those troubles. Ms Cummings outlines several areas of peril, but the greatest is the loss of seed diversity.

Industrial processes rely on control, and control requires uniformity. Industrial agriculture, which is now almost universal in the West, controls its markets by controlling seed varieties. Each seed company boasts of its "broad line" of varieties, and such lines do seem broad: ten or twenty varieties of a particular species. But contrast that with the contents of seed banks, that have existed or do exist today, with their tens of thousands of natural varieties per species.

For example, around the world there are more than five thousand varieties of rice being grown, and most of this diversity is in the hands of small planters who share seed among themselves, continually seeking the best variety for their combination of soil type and climate. Because all the grains are wind-pollinated, rice growers know that their own fields will produce best if they and their neighbors all grow good, strong varieties. It is thus in their interest to give the seeds of better varieties to any of their fellows who are having trouble with their harvests, in hopes that the winds will carry a good mix of the strongest rice varieties, to the benefit of them all.

Contrast this with the grower who buys seeds of only one variety for a million-acre planting, a variety that is a sterile hybrid, so that he cannot even keep back a part of the harvest for planting the following year. Not only that, he must sign a contract not to try to do so, in order to get these special seeds at all!

The dirty secret behind the bumper crops that super-seeds produce is that their harvest will utterly fail without constant, costly application of fertilizers and "crop protection" chemicals. The upshot is this: the small farmer using traditional seeds may have a lower yield per acre, but the cost to produce it was much less.

The risk of large monocrops is not just that a new pest will arise to decimate the entire season's crop. It is that a huge number of non-patented varieties is ignored, many are no longer planted, and many go extinct.

This is a tiny tip of the iceberg. Author Cummings sees hope, in spite of the perils. Increasing numbers of farmers, seeing the hypocrisy in the two statements I began with above, are rejecting the industrial model of agriculture. One promising trend is illustrated by Wes Jackson of the Land Institute in Salina, KS. He has sought to produce a plot of ground that will "produce like a farm field but act like a prairie". A healthy bit of prairie, say a meter square, contains dozens or even hundreds of species. It has the wherewithal to respond effectively to the vagaries of almost any year's weather.

I remember reading, years ago, of the efforts at Malabar Farm in Ohio, Louis Bromfield's experimental farm at which he sought to rebuild the topsoil. He was a particular advocate of multi-cropping, though in his book Malabar Farm he primarily illustrated the idea with a duo-crop of alfalfa and corn. Organic farmers are busily working at ways to extend this idea, taking advantage of natural synergies that abound around us.

Here is a question for you: Why is the ground kept so clear in an orchard? I lived across the street from fruit orchards as a boy. I remember the farmer saying that the right kind of undergrowth made the trees healthier, rather than "robbing" them of water or nutrients. But the ground was kept clear for the convenience of farm workers and harvesters. A pity.

There are many good ideas in Uncertain Peril, and lots of hope. May the hopes outstrip the perils, for our future rests upon them.

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