The weed resistance crisis in American GMO agriculture
The purchase of genetically engineered (GE) seeds requires a signed legal contract with a licensed seller. The contract specifies all crop management practices and requires the farmer to purchase herbicides (i.e., Roundup or Glufosinate) sold only by this same seed company.
Years ago, biotechnology seed producers increased crop plant tolerance to Roundup by changing the source of the genetically engineered gene from a plant to a bacterium. This means farmers can apply even higher concentrations of Roundup without killing the crop and the seed companies can sell more of this chemical product.
According to the U.S. Department of Agriculture, U.S. farmers now use more than 180 million pounds of Glyphosate (active Roundup ingredient) every year. This is up from 15 million pounds when genetically engineered seeds were first introduced.
Unfortunately, spraying repeatedly at the highest herbicide dose tolerated by crops doesn't always destroy all the weeds. The president of the Arkansas Association of Conservation Districts recently stated, "Resistant weeds are the single largest threat to production agriculture that we have ever seen." Other farmers complain that the weed problem puts their management system back to where it was 20 years ago, i.e., prior to the genetically engineered organism.
Farmers say because they are paying a premium price for current versions of genetically engineered seeds plus an additional technology fee, they are obligated to make use of that herbicide and spray, spray, spray to get rid of weeds that adversely affect crop yields. Hence the phrase, "Roundup is the agricultural heroin." Farmers are hooked on its use.
The genetic engineering seed industry has responded to the resistant weed crisis with two unrelated strategies. First, because the weed resistance problem in some U.S. locations is so severe, some GE seed companies are exploring new applications of "gene silencing strategies." Strategies include RNA interference which involve silencing certain genes that contribute to weed and insect resistance. The genes to be silenced are hoped to exist only within the pests and not within beneficial life forms. EPA has just remarked that such new molecular strategies bring challenging and new regulatory issues.
Secondly we can say this next crop season will bring genetically engineered soy and corn and perhaps cotton and other plant species resistant to various combinations of Roundup, Glufosinate, 2,4-D, Dicamba, isoxaflutole, thifensulfuron, and more. It's no wonder that some scientists say we are in the herbicide treadmill state of GE crop management. I would also say we are in the molecular biology treadmill as well, trying to adapt newer and newer environmentally unproven technologies to solve a never-ending natural response to unnatural agricultural practices.
Bringing back 2,4-D also forces us to remember it is a known poison that causes serious health problems linked to lowered sperm counts, liver disease and Parkinson's disease. Laboratory animal studies also show that 2,4-D adversely affects hormonal, reproductive, neurological and immune systems. It is widely believed that most of these health problems arise through a contaminant in 2,4-D called dioxins. Industry tells us that technology has all but eliminated that contaminate. However, a recent report indicated extremely high concentrations of dioxin were detected in a batch of 2,4-D exported from China. Also, 2,4-D (and Dicamba) come in formulations that are notorious for their volatility which means an ability to drift long distances (up to 100 miles) and can destroy highly sensitive crops growing within our county, including grapes. Herbicide drift into local farms may also destroy their organic certification status.
Government regulators report that Isoxaflutole is a probable human carcinogen. It is also of environmental concern due to its rapid movement into surface and groundwater supplies. Its use is restricted in three Midwestern farm states and federal regulations previously restricted its use to just 5 percent of the corn crop in any single year.
Now we learn that the USDA. has just approved Isoxaflutole with unrestricted applications to the new resistant soybean variety being sold by Bayer and planted on millions of U.S. acres. Since Roundup-resistant sugar beets are currently being grown in our county, the question arises as to not whether, but when this seed company will also join the herbicide and molecular biology treadmill, experimenting with sugar beets resistant to these new types of poisons.
Will Jackson County organic family farm operations have to cease operating because of pesticide drift concerns and cross-pollination? Are the tiny vineyards in my neighborhood also at risk from 2,4-D overspray?
Ramon J. Seidler, Ph.D., is a professor of microbiology and a retired senior scientist and team leader for the Environmental Protection Agency's biosafety program.