Is This Sustainable Agriculture? Resistance to Engineered Bt Corn on the Rise

, former senior scientist, Food and Environment | December 5, 2011, 10:16 am EDT
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EPA has responded to reports of resistance by one of the worst insect pests of corn, called rootworm. In the past, about a billion dollars’ worth of chemical insecticides per year were used to control this pest  in the U.S.

Starting in 2009, according to EPA monitoring records, possible increases in resistance to the Bt toxin Cry3B were noted. In at least one case, Monsanto appears not to have done needed follow-up studies to determine resistance to its gene.

As I reported earlier, recent research has found strong evidence of Cry3B Bt-resistant rootworms, which is causing failure to control the pest on some farms. One important implication of this is that more chemical insecticides may be used to control the resistant rootworms.

Entomologist Aaron Gassmann (left) of Iowa State University identified rootworms resistant to Bt. Photo by Stephen Ausmus, USDA.

The good news is that the agency is recommending remedial action, maybe for the first time for GE crops, to address the problem. EPA recommends that farmers that experience failure of Bt corn use other means to kill rootworms, rather than exacerbating the resistance problem by continuing to use Bt corn. EPA also recommends beefed-up monitoring of farm fields to better detect resistance.

Unfortunately, EPA’s response may be a case of too little too late. More aggressive action is needed if this problem is to be corralled.

What EPA should do

When EPA was originally considering approving corn containing Cry3B, scientists recommended that only 50 percent of corn acres on a farm contain the Bt gene. This “refuge strategy” was to prevent or delay resistance by increasing the probability that rare resistant insects mated with non-resistant individuals from the non-Bt parts of the farm. The resulting offspring would not be resistant.

EPA instead sided with industry and a minority of scientists and went with a 20 percent refuge, which probably has contributed to the current problem.

EPA should require a larger refuge to delay this problem in areas where resistance has not yet emerged.

EPA should also withdraw the still-smaller five percent refuge for corn that contains two Bts to control rootworm— Cry3B and Cry34/35—so-called “SmartStax”. Where resistance to one Bt already exists, the likelihood of resistance developing to the second Bt is greatly increased.

Widespread loss of both Bts would likely result in greatly expanded use of chemical insecticides.

In discussion with Bruce Tabashnik, entomologist with the University of Arizona and a widely acknowledged expert on Bt, he said that there  is currently enough data on rootworm resistance to Cry3B to substantially raise concerns about the use of a five percent refuge for corn containing Cry3B and a second toxin that targets rootworms.

Third, EPA’s focus on remedial action by individual farmers is not likely to prevent the spread of resistance. It is highly likely that the problem is more widespread than has been officially reported. And although rootworm beetles do not move as far as many other insects, they will certainly not stay on individual farms. So EPA needs to consider a regional approach for controlling the spread of resistant insects.

EPA should also convene a Scientific Advisory Panel (SAP) to get more formal input on what to do.

The “root” of the problem—too much corn

The resistant rootworm issue is really just a symptom of a much bigger and more fundamental problem: Midwestern U.S. agriculture is not sustainable. This is because good agroecological practices like alternating, or rotating, crops are not widely practiced due to the drive for shortsighted gains in efficiency.

Crop rotation and other practices greatly reduce pest problems, and rootworm in particular would not even be a big problem if diverse crop rotations were used. But growing demand for ethanol from corn has increased corn acres, pushing more corn-on-corn and fewer corn-soy rotations (let alone more robust rotations that include multiple crops).

Current practices, including genetic engineering, have been pushing us toward greater simplification of our cropping systems—the opposite of diverse, biologically-sound agriculture.

Until we embrace a truly sustainable agriculture, the types of remediation recommended by EPA will merely be a band-aid on a severely wounded patient.

Posted in: Food and Agriculture

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  • Anthony Samsel

    I am very active in voicing my concerns over GMO’s with Senators, Congressman and Government officials. Here is an article I wrote published by the Organic Consumers Association concerning GMO’s and World Food Day.

    Here is a letter I sent to USDA expressing concern and opinion with Genetically Engineered Sugar Beets.:

    As a Scientist and also a retired owner of a commercial vegetable farm operation in the Northeast, I strongly disagree with the draft Environmental Impact Statement (EIS) for RoundUp Ready Sugar Beets, which seeks full deregulation.

    It is apparent that members of the Agency do not possess an understanding of Agriculture, pollination and sustainability of natural biologic systems. Neither do they posses an understanding of the adverse health effects of Genetically Engineered Food and the threat these foods pose to human, animals and diverse ecosystems systems. Historically, decisions involving genetic engineering ignore the ‘ Precautionary Principle’.

    Horizontal Gene Transfer and recombination of Transgenic DNA is inherently designed to jump into Genomes sometimes through virus or Bacterial Plasmids. This fact makes Transgenic DNA different and more dangerous than naturally occurring DNA. Agrobacterium tumefaciens and Cauliflower Mosaic Virus (CaMV) are two major vectors for transferring DNA creating transgenic plants. Agrobacterium not only transfers its genes to plant cells it can also accept genes from plant cells by a process known as retrotransfer. Agrobacterium has a known ability to attach and Genetically change several Human cell lines making it a major concern in the spread and creation of new pathogens resistant to drugs and antibiotics.

    Genetically Engineered plant crops are not only grown outdoors in unprotected environments for food, they are grown to produce Biofuels, Botanical drug factories for Pharmaceutical drugs, Botanical Weapons factories for production of Bacteriological Weapons, Antigens and more.

    The Biotech Industry is systematically destroying Biodiversity as we know it. Increasingly popular within the industry is the use of Genetic Engineering to produce vaccines and pharmaceuticals in plants. The use of food crops including vegetables and grains for their production represents a real and present danger to all forms of life. Genetically Engineered Rice and Barley are popular choices with a danger now of vaccine and pharmaceutical drug laced Beer from cross pollination and or product distribution error.

    The EIS acknowledges the threat of contamination to organic seed and food crops is real compromising the livelihood, genetic integrity, and faith of the organic label. The EIS further requires USDA to reject Monsanto’s petition seeking a determination of non-regulated status. Monsanto and other Corporations engaged in the Genetic Engineering of Plants, Fish, Animals, Birds, molds, bacteria and other life forms, in my opinion are Terrorist Organizations and as such should be pursued to the full extent of the law for their threat to the Health and National Security of the United States of America and other Nations of the World. They are creating a food monopoly based on a Genetically Engineered, gene corrupted food supply from which there will be no return.

    1. Sugar beets, the latest Genetically Engineered crop seeking approval are wind pollinated crossing with related vegetable species. Bees and other pollinating insects will additionally carry and also ingest Genetically Engineered pollen corrupting plants themselves and honey in the process.

    The species in the EIS (Beta vulgaris) is a vegetable crop species which is wind pollinated. Although insect pollination occurs in beets, wind accounts for most pollination. Beets are self-incompatible, where each plant must have pollen from a different individual to produce viable seed.

    Table beets and swiss chard varieties have many flowers per plant, producing large amounts of pollen. Compatible pollinating crops within the Beta vulgaris species include table beets, chard, and sugar beets, all are sexually compatible. Pollination between any of these crops will occur and result in viable offspring producing viable seed.

    Research has demonstrated that beet pollen can travel over 12 miles. However, violent storms can carry pollen hundreds to thousands of miles. There is no distance that completely isolates two cross-pollinating crops 100 percent of the time, particularly in highly concentrated seed production areas like the Willamette Valley.

    2. Contamination is inevitable, only a matter of time.

    Once contamination occurs, farmers cannot detect the presence of a transgenic trait without testing, neither can they remove foreign DNA from the crop. Contaminated seed that is planted unknowingly, will spread unwanted Genetically Engineered Genes.

    Contaminated seed may be used as stock for subsequent seed crops. Contaminated seed in the hands of farmers or gardeners scattered geographically, can cause wider distribution of Transgenic contamination.

    Contamination also spreads through unintentional flowering when crops encounter stress — called “bolting” — releasing pollen to other susceptible populations.

    Seed crops from this species grown during the first year of the biennial cycle can flower prematurely. Excessive cold temperatures can also produce pollen early from plots that are not normally considered a contamination risk.

    Escaped seed from sugar beets growing in roadside ditches and other areas not under cultivation will spread Transgenic traits further increasing contamination events.

    Human error is inevitable, mistakes with the physical mixing of roots in breeding programs spreads genetic traits to other seed lots.

    3. Unwanted spread of GE traits threatens markets and livelihoods

    Maintaining the genetic purity and proper isolation distances with these crops in an outdoor unprotected environment is difficult as it is impossible. Genetically Engineered Food is outright rejected by various markets. Cross-pollination between a GE crop and a non-GE crop of the botanically related species inadvertently causes problems. Contaminated seed is not acceptable because:

    Contaminated seed cannot be sold into countries that do not allow GE crops or products.

    The contaminated seed does not comply with USDA standards for organic certification, which does not permit GE content in organic seed. It can therefore not be sold as organically certified seed in the US nor to any international organic seed market that adheres to the standards established by the International Foundation of Organic Agricultural Movements.

    4. GE sugar beets put chard and table beet seed at risk as well as humans and animals fed the beets and beet sugar.

    The integrity of organic seed and food crop products are at risk. The quality of organic seed is dependent on genetic purity, being free of GE contamination. Of particularly concern for table beets and chard are Botanical relatives to sugar beets capable of cross pollination. Washington and Oregon account for 80 percent of US chard and table beet seed production, and 50 percent of world chard and table seed production. This valley is home to a high value specialty seed trade with buyers with a worldwide market particularly in the Pacific Rim and European Union will reject contaminated seed. Companies are already looking to produce seed elsewhere, in different US regions and abroad, because of contamination concerns.

    5. Organic farmers shoulder the burden of protecting the integrity of organic seed

    The burden of protecting the integrity of organic seeds, agricultural products, and markets is solely on the shoulders of organic farmers. This is an imbalanced and unfair burden.

    Contamination by Genetic Engineering is inevitable, farmers have no recourse to recoup damages because the question of who is liable has not been determined. They are left with the economic and agronomic costs of detecting and eradicating GE material; losing the genetic integrity of seed on which they rely; taking measures to avoid future contamination; and selling contaminated products into the conventional markets and losing organically produced products.

    As a Scientist and retired Agribusinessman, there is no room for compromise, USDA must reject Monsanto’s petition for deregulation. Readers are encouraged to contact Secretary of Agriculture, Tom Vilsac by letter or email at the USDA and President Obama at the White House to voice your concern.

    Anthony Samsel is a Scientist and member of the Union of Concerned Scientists, The Collaborative on Health and the Environment and former consultant to Arthur D. Little, Inc. Cambridge, MA, environmental consultant on many EPA and Army Corps of Engineers environmental projects and impact statements and the author of “The Guide To Water Cleanup Materials & Methods”.

    • Anthony Samsel

      Comment removed by moderator.

      • Anthony Samsel

        Monsanto and BASF have been collaborating on New lines of GM plants which are resistant to different herbicides like Banvel (Dicamba) the next Roundup. Knowing that Roundup could be forced off of the market and also developing GM plants resistant to a wider variety of herbicides due to herbicide resistance of emerging super weeds the fight will continue with dire consequence.
        Starvation and World Famine are also possible outcomes from the GMO business. Glyphosate chelating damage goes further not just with Super Weeds but Super Bacteria resistant to antibiotics threatening poultry, sheep, cattle, pigs and animals that live in the wild.
        It is now known that Roundup and many other brands of glyphosphate ARE ENDOCRINE DISRUPTORS AND CAUSE CHROMOSOME DAMAGE. In 2009 this study showed endocrine disruption at sub-agricultural use doses.…/19539684
        This study showed genetic chromosome damage, aberrations and induction of…/PMC2809416
        Recently, a new Genetically Engineered virus was created in the lab which has the potential to kill up to half the world’s population. The virus, an H5N1 bird flu strain is more contagious than the human seasonal flu that kills tens of thousands of people every year. This could likely cause many more fatalities if it escapes or is deliberately released.
        This virus was created by Ron Fouchier who, at the Erasmus Medical Centre in Rotterdam, Netherlands. His work was presented at the Influenza Conference in September 2011. Academics and bioterrorism experts are arguing whether this information should be patented or published and released. As a scientist who believes in Bio-ethics I must say this research should never have been done.

    • Know It When I See It

      Comment removed by moderator.

      [Jesus Christ, this is a pretty heavily censored website. Can’t risk any dissenting opinion diluting the UCS propaganda, now, can we?]

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  • danitza galvan

    Oh, I see. Pesticide companies and chemists feeding the masses, huh? Nothing but poetry otherwise? What part of unsustainable didn’t you get?

  • GreenJeans

    Brilliant! No corn, no pests, no problem.

    Brazil will feed us, right? Or, maybe China.

    We definitely need more poets and faux-scientists instructing us how to farm.

    • Andrew

      This article is not suggesting that we stop growing corn. There are hundreds of different types of corn (you’ve heard of blue corn, right? Well that’s just one of many). There are some types of corn that are resistant to this specific disease, but susceptible to other diseases (and vice versa). Planting multiple different types will keep the pests and diseases from adapting and evolving as quickly (it’s not faux-science; this has been happening naturally for thousands of years). The idea that one type of corn is “perfect” and we need no other types is what makes it easy for pests to adapt and wipe out our entire food supply. Then we really will have to worry about being fed by another country. There is no “perfect” model. The world thrives off of diversity. Listen to the poets; you might learn a thing or two.