Losing Bt

The discovery and development of microbial pesticides like Bt, or Bacillus thuringiensis, was big news twenty years ago. These have proved remarkably effective over the intervening decades and have become a near essential component of many organic gardeners’ pest control programs. Yet it is likely that we will be losing some of these valuable biological tool in the next ten years—maybe even sooner.

Genetic engineers for the multinational agricultural chemical companies (tagged “Big MACCs” by one tongue-in-cheek trade journalist) have found a way to insert a gene they isolated from the Bt bacteria (and then patented), into two major American field crops—corn and cotton—so that the plant tissues themselves contain the toxin produced by the Bt organism. This makes every bite a pest takes poisonous and gives near perfect control of pests in the field, but it also means that resistance to the Bt toxin, previously unheard of, is starting to develop.

Why? Organic gardeners, who use only as much spray as will do the job, and only in the immediate area of a pest outbreak, can be sure that any pests which survive will mate with those who were not exposed, and thus their offspring—following the laws of genetics—are less to develop a resistance to Bt. But in order to earn back the enormous investment the Big MACCs have made in the biotechnology to implant the Bt gene into their crops, they have covered the landscape with millions of acres of patented “Bt-enabled” crops (up to 90 percent of planted acreage of corn and cotton), every cell of which will contain the toxin. And this enormous evolutionary pressure on the pest species can be expected to induce  resistance within as little as three to five years.

Company researchers have a plan however: they insist that farmers plant, say, 4 percent of their land to non-Bt crops (so there will be at least some unexposed mating partners), with the result that resistance can be put off long enough for alternatives to be developed. Their second plan: isolate slightly different versions of the Bt toxin and alternate them so that the pests don’t develop resistance quite so quickly. Of course this also means — like with the “tail-fin wars” of Detroit in the late 1950′s and early 1960′s, that there will always be new product to sell.

In the meantime, of course, organic growers will be relegated to collateral damage as our best long-term, sustainable control for vegetable garden pests will be ruined, and we will all be made dependent on the chemists’ newest products.

The most galling part of the whole scam is that when we want to protect land from development to preserve biological diversity, the “Wise Use” movement insists that this represents a “taking” of property rights (read: development rights, or logging or mining rights) and that the landowners affected should be compensated. But where are they when private companies want to “take” the livelihood from organic farmers and gardeners by privatizing and then destroying our best means of controlling damaging pests? What about compensation for the “taking” represented by the privatization of the gene pool and other creations of nature?

ShepherdLosing Bt

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