Roundup Ready Soybeans
Herbicide-tolerant crops are engineered to enable crops to withstand doses of herbicides that would otherwise kill them. These crops are generally developed by the manufacturers of the herbicide with the hope of increasing the sale of that herbicide. Roundup ReadyTM crops, for example, are produced by the Monsanto company, the producer of the herbicide Roundup, a billion-dollar product that generates about 40 percent of the company's annual revenue. The projected planting of perhaps 12 million acres of Roundup ReadyTM soybeans will substantially increase Monsanto's revenues as farmers switch from their current herbicide to Roundup.What do these crops mean for the environment? The environmental benefit Monsanto claims for Roundup ReadyTM soybeans is associated with the move away from popular herbicides like atrazine, whose active ingredients persist in the environment. Even granting that glyphosate is less toxic than atrazine and generally to be preferred to it, a switch from one herbicide to another does not result in an environmentally sound agriculture.
Glyphosate is highly toxic to plants and fish. Few who care about the environment welcome the annual dousing of 12 million acres of American farmland with such a chemical. In addition, many preparations of glyphosate are dissolved in so-called inert ingredients that can also be toxic. More fundamentally, it is highly unlikely that chemical companies that produce herbicide-tolerant plants will ever develop products that cut into their substantial herbicide revenues. Thus, to the extent that Roundup ReadyTM products are environmentally beneficial, this is likely to be the limit of progress in that direction. The bottom line: US agriculture remains shackled to intensive chemical use.
Moreover, use of glyphosate-tolerant soybeans poses environmental risks. Herbicide-tolerant crops can transfer their tolerance trait to nearby related plants and weeds. While there are no such relatives in the United States, they do exist in other parts of the world, where the resulting glyphosate-resistant weeds will make weed control much more difficult. In the United States, the use of glyphosate on millions of acres will intensify the selection pressure for resistance in weeds unrelated to soybeans. As weeds become resistant, farmers will have to use more glyphosate, accelerating the downward spiral toward the loss of glyphosate as a weed-control tool. In addition, the glyphosate-tolerant plants could have effects on soil ecology that have not been assessed.
Are there alternative approaches to weed control other than intensive, prophylactic herbicide use? Yes, there are new tillage methods, multiyear crop rotations, cover crops, and other techniques of biointensive weed management. Scientists also urge farmers to accept of levels of weeds that may give their fields a messy appearance but have no economic impacts.
