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MailTribune.com
  • In support of genetically engineered crops

  • A working definition of organic produce: It ain't gene-engineered, it ain't sprayed with pesticides, and it must be pure of breed, not occasionally miscegenated with gene-engineered pollen.
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  • A working definition of organic produce: It ain't gene-engineered, it ain't sprayed with pesticides, and it must be pure of breed, not occasionally miscegenated with gene-engineered pollen.
    Once there were but four ways to weed crops: flooding, burning, tilling and removing individual weeds by hand, hoe, or trowel. Today, a fifth way to weed crops uses gene-engineered crop resistance to biodegradable herbicides such as Roundup.
    The long-grass great prairies of the Midwest have long been replaced with stands of corn and soybeans and have recently been untouched by a deep plow. During the 1960s and '70s, this black-dirt topsoil, the thickest in the world at 2 to 7 feet, was washing away at the rate of half an inch per year from plowing and spring runoff. Now this entire swath of black dirt land sees no plow, erosion is almost insignificant, the spring runoff into streams is rather clear, and the white fish have returned. The muddy Mississippi is no longer so muddy and dredging of the Mississippi delta is less onerous. So this new weeding method is one of the greenest technologies to come along in a century.
    Insect and disease resistance genes are supplanting the previous intensive use of pesticides. Many of you have purchased spores of the soil bacterium Bacillus thuringiensis to spray on your flowers and vegetables to kill leaf-munching insects.
    Hey! This is very green, and you can even drink or aspirate the spore solution with no effect. Now, the genes from B. thuringiensis are in most corn seeds — Bt-corn — making ear worms no longer a pest. And Bt-cotton, Bt-peanuts and Bt-potatoes are reducing pesticide use in other areas of the U.S. Very green!
    American chestnuts aren't roasting on an open fire anymore because of the chestnut blight fungus. However, a rust resistance gene from wheat was introduced into a chestnut cell's genome and the cloned and propagated trees are rust-resistant. They will soon be planted over old strip mines along the East Coast.
    Monsanto's DroughtGard corn will next year be planted in the Midwest to reduce the need for irrigation, providing more water for fish, aquifers and urban areas. And the list goes on, with each introduction making for more food, more and cleaner runoff, less pesticides — more "green."
    Admittedly, if farmer A plows and plants a field of organic popcorn near Urbana, Ill., some seeds will come up as engineered from his neighbor's airborne pollen and won't pop. But these no-pops are no more frequent than what previously came up from his neighbor's nonengineered corn pollen. However, his neighbors no longer have earworms to infect Farmer A's earworm-sensitive maize, so this situation is like most of the children in a school being immunized so infrequent cheaters don't get the disease.
    A story and philosophy: Plants don't have feet so they can't run from herbivores. But they can make spines, thorns and toxins to protect themselves. Generally, these toxins, often alkaloids, are bitter tasting and bred out for human consumption, making tasty vegetables herbivore-sensitive and more pesticide dependent.
    Once upon a time, an organic commune found a celery strain that was naturally resistant to herbivorous insects and planted it without pesticides in a big field for organic sale. But the pickers got severe rashes on their forearms. Well, it turns out that celery's major protective toxin is psoralin, a tasteless natural pesticide whose levels were highly elevated in this organic celery strain.
    Psoralin binds to DNA and, in the presence of light, covalently cross-links both adjacent bases and opposite bases. It is a potent clastogen (chromosome breaks) and mutagen. So in this case, organic meant you were really getting screwed.
    Bruce Ames invented the Ames test for mutagens and found that while 50 percent of all chemically synthesized small molecules were positive for mutagenicity, so also were 50 percent of all "natural" organic small chemicals, those extracted from plants. Admittedly, one of the major distinctions between these two classes of small molecules was higher biodegradation rates for natural molecules.
    In summary, Midwest farmers are feeding the world using green techniques while the Jackson County farmers are trying to supply local farmers' markets with higher quality but labor-intensive "organic" produce using old-fashioned brown techniques, all the while snubbing the county's Food Stamp recipients who can't afford labor-intensive produce and seem to lack a county lobby.
    Gerald Holmquist, Ph.D., is a retired molecular biologist who has published multiple articles on plant genetics in scientific journals. He lives in Shady Cove.
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