1.Monsanto EU GM Maize Plans Undermined by Damning US Report
2.Is This Sustainable Agriculture? Resistance to Engineered Bt Corn on the Rise

EXTRACT: "Current practices, including genetic engineering, have been pushing us toward greater simplification of our cropping systemsthe 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." – Doug Gurian-Sherman (item 2)
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1.Monsanto EU GM Maize Plans Undermined by Damning US Report
GM Freeze, 7 Dec 2011
http://www.gmfreeze.org/news-releases/173/

*Resistance in maize pest reported in four states

A review by the US Environmental Protection Agency (US EPA) [1] describes Monsanto’s insect resistance monitoring strategy for Bt maize in the US Midwest as “inadequate and likely to miss early resistance events”. It also highlights how the crop itself may be causing the problem and how a failure to enforce mitigation measures, like refuges and rotations, is making it worse.

The review confirms that in Iowa and Illinois a major pest of maize, the western corn rootworm, has developed resistance to the toxic Cry3Bb1 protein present in Monsanto’s MON863 and MON88017 Bt maizes. It goes on to report “severe efficacy issues for Monsanto’s Cry3Bb1 trait” in Minnesota and Nebraska.

Monsanto has applied for authorization to grow MON88017 in the European Union. GM Freeze published a review of insect resistance in Bt crops earlier this year [2] and is releasing today a critique of the European Food Safety Authority’s support for approval of EU cultivation of MON88017. [3]

The EPA findings are not a surprise. Laboratory breeding experiments with western corn root worm have demonstrated that, “Resistance evolved after just three generations of selection on Cry3B maize."

Monsanto's approach to monitoring the problem comes in for severe US EPA criticism because of:

*Sampling insects too far from damaged crops.
*Adopting too high a damage threshold before further action is taken.
*Failure to sample for resistant adults from problem fields.
*Failure to take follow up samples in the next season if adults were not sampled.

The US EPA review suggests the breakdown in effectiveness of GM maize is caused by a number of factors including:

*Bt plants producing too low a dose of toxin to kill pests, and hence fostering resistance developing in those that survive.
*Farmers failing to plant non-GM crops refuges to ensure sufficient non-resistant adults are present to mate with resistant individuals, preventing the recessive resistance from becoming dominant in the population.
*Continuous cultivation of the same Bt maize on the same land for several years without rotation.

The US EPA also presents data showing the amount of toxin needed to kill the western corn root worm in problem areas has increased by as much as one hundred times.

The Agency warns that merely resorting to other GM maize varieties using several Bt toxins may not provide a lasting solution:

"If Cry3Bb1 resistance has indeed developed (ie, 'confirmed resistance’), a 5% refuge for pyramids (ie, SmartStax expressing Cry3Bb1 and Cry34/35 targeting corn rootworm) will be substantially less durable and could ultimately compromise the second unrelated toxin used to control the pest (ie, in this case Cry34/35)."

So far US farmers have responded to the crop losses caused by the outbreak of the insect resistance in Bt maize by using additional pesticides to "bomb" adult beetles, adopting other GM varieties with different Bt toxins present, or a combination of approaches. This increases the number of biotech companies involved, but may not be effective and increases the environmental burden of industrial agriculture.

Commenting Pete Riley of GM Freeze said:

"Monsanto's approach to monitoring resistance in this major pest of maize has rightly been heavily criticized by the US EPA.

"Predictably all Monsanto and the US EPA can suggest is more pesticides and more GM. It seems likely that these will also breakdown then what?

"What's happening to Bt crops in the US Midwest underlines that GM is not a panacea and it is not sustainable. There is an urgent need for scientists and farmers to develop new systems of agronomy based on agroecology, which we know is an system effective over time.

"Europe's precautionary approach to GM crops is proving very wise as time passes and more and more problems with GM come to the fore. Now is no time to change."

Calls to: Pete Riley 07903 341065
Notes

[1] US EPA, Office of Chemical Safety and Pollution Prevention, 2011. Updated Biocides and Pollution Prevention Division Review of Unexpected Cry3Bb1 Corn Rootworm Damage (doc ID EPA-HQ-OPP-2011-0922-0003 – pdf also available from GM Freeze upon request)

2. See GM Freeze Insect Resistance to Bt Toxins in GM Insect Resistant Crops

3. See GM Freeze Papering Over the Cracks: EFSA's opinion on cultivation GM MON88017 maize in Europe Mitigation is not enough
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2.Is This Sustainable Agriculture? Resistance to Engineered Bt Corn on the Rise
Doug Gurian-Sherman, senior scientist, Food and Environment
Union of Concerned Scientists, December 5 2011
http://blog.ucsusa.org/is-this-sustainable-agriculture-resistance-to-engineered-bt-corn-on-the-rise

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 Cry34/35so-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 problemtoo 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 systemsthe 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.

About the author: Doug Gurian-Sherman is a widely-cited expert on biotechnology and sustainable agriculture. He holds a Ph.D. in plant pathology.