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DNA . Hot Science . Gallery of Genetic Modifications
Tomatoes Genetically Modified Tomatoes
Bt Corn
Golden Rice
Roundup Ready SoyBeans
Roundup Ready Soybeans
Roundup Ready Soybeans

Roundup Ready Soybeans have been engineered by the Monsanto Corporation to contain an in-plant tolerance to the Roundup WeatherMAX herbicide. This allows farmers to spray their crops with weed killers without worrying about hurting the crops themselves. Monsanto claims their Roundup Ready Soybean System "expands yield potential for more than a $19.00 per acre advantage" and is a great boon to farmers.

Proponents of genetic engineering feel such soybeans may be advantageous for the environment as well, arguing that herbicide-resistant plants -- as well as crops like Bt corn that produce their own insecticides -- will reduce the use of artificial pesticides. Yet critics point to USDA data showing that, while the number of herbicide treatments on soybeans resistant to glyphosate (the active ingredient in Roundup herbicides) has decreased, the total amount of glyphosate used may actually have increased. (Critics have also suggested that Bt corn has had little impact on the overall use of corn insecticides, as farmers do not usually use insecticides to control corn borers). Moreover, there are concerns that these crops, both those engineered to produce pesticides and those engineered to withstand weed killers, may result in strains of super bugs and super weeds that evolve a resistance to the plants' genetic modifications.

Another related issue concerns the seeds of herbicide-resistant soybeans. Traditionally, each year at harvest time farmers save a portion of the seeds from their crops for the next season. Yet, growers using genetically engineered seeds must sign a contract agreeing not to save and reuse any of the engineered seeds. Proponents state that no one forces farmers to choose genetically engineered crops, but critics suggest that growers increasingly have little other choice: Roundup Ready soybeans account for around three quarters of soybean seed sales. Court decisions -- Monsanto v. McFarling, decided by the U.S. Court of Appeals for the Federal Circuit in 2002 and Monsanto v. Trantham, a federal district court case decided in 2001 -- have supported Monsanto's right to prevent farmers from saving the patented seeds.