New Monsanto-Dow ‘Stacked Resistance’ GE Crops: Big Mistake or Bad Idea?

'poison' signOver the past twenty years, Monsanto’s Roundup Ready glyphosate resistant GE crops have come to dominate the agricultural scene in the US. Predictably, Roundup Ready ‘superweeds‘ have evolved similar resistance, resulting in ever-increasing herbicide application and escalating use of unsustainable farming practices.

The biotechnology industry’s proposed solution? GM crops with combined resistance to glyphosate AND an Agent Orange ingredient called 2,4-D — so now we can have even MORE herbicide use and even TOUGHER intractable weeds! Yay!

What could possibly go wrong?

Quick Review: Roundup, the Poison We Can’t Get Enough Of

Monsanto’s Roundup Ready GE crops are resistant to the herbicide glyphosate. Due to this resistance, growers can douse fields with high levels of Roundup glyphosate-based herbicide, killing everything not engineered with the gene for glyphosate resistance. In theory, this was supposed to increase yields and reduce herbicide use.


What’s actually happened — unshockingly, to anyone familiar with basic principles of biology or natural selection — is that weeds have evolved to adapt to their Roundup-drenched environment, and have developed independently what Monsanto spent years and billions on inventing and marketing: Roundup resistance.

Growers now committed to Roundup Ready products have had to continually escalate herbicide application, to keep yields at moderately acceptable levels. Unfortunately glyphosate, like most pesticides and herbicides, doesn’t usually stay where it’s put. It gets bored, and goes out on the town — or rather, into the groundwater, air, and ecosystem.

For this and other reasons, a recent report released by the Union of Concerned scientists gave Monsanto a stern talking-to about what the term ‘sustainable agriculture’ actually means, and why what they’re doing isn’t it.

In terms of health effects, glyphosate has been shown to cause a number of problems; and Roundup is even more toxic than glyphosate, because of the other ingredients it’s mixed with for optimal killing action. Toxicity highlights include birth defects, miscarriages, and endocrine disruption. Research also suggests that glyphosate/ Roundup may also be linked to non-Hodgkin’s lymphoma and multiple myeloma.

Unsurprisingly Roundup/ glycophosate wreaks havoc on beneficial insects, amphibians, and birds who are foolish enough to try to exist in their natural habitats, anywhere near Roundup Ready fields.

Thank You Sir, May I Have Another?

Dow Agrosciences has engineered a strain of corn resistant to an herbicide called 2,4-D, currently under USDA review for deregulation.

Developed in the 1940’s, 2,4-D has been shown to double the incidence of birth defects in children of pesticide applicators. It is  suspected to increase incidence of non-Hodgkins lymphoma. 2,4-D is also reported to negatively effect endocrine and immune function, and to impair respiratory and central nervous system function. According to one toxicity summary, at high levels of exposure 2,4-D acts as a central nervous system depressant that can cause severe health problems:

[High rates of exposure to 2,4-D] can cause stiffness of arms and legs, incoordination, lethargy, anorexia, stupor, and coma (EPA, 2007). It is also a respiratory system irritant that can cause prolonged difficulty breathing, coughing, burning, dizziness, and temporary loss of muscle coordination (EXOTOXNET, 1996). Other symptoms of 2,4-D poisoning include irritation, inflammation, itching, and headache (CDC NIOSH, 2005). The primary target organs of the chemical are the eye, thyroid, kidney, adrenals, ovaries, and testes (EPA RED Decision, 2005).

Long-term animal studies of 2,4-D’s chronic exposure have shown effects on the blood, liver, and kidneys (EPA, 2007). Studies have also revealed slight chronic symptoms including a reduction in weight and changes in blood chemistry (NPTN).

It is observed to be a developmental toxicant. Some observed effects are increased gestation length, skeletal abnormalities, and effects on the thyroid and gonads (EPA RED FACTS, 2005).

Unsurprisingly, 2,4-D is also toxic to birds, bees, and fish.

The Punch Line (Don’t Laugh, They’re Serious!)

So how can we save the agricultural world from resistant weeds and escalating herbicide use, caused by Roundup Ready GE crops?

According to a petition recently submitted to the USDA, Monsanto and Dow have had the brilliant idea to team up and engineer corn with Roundup resistance AND 2,4-D resistance. Ta-da!

Isn’t it great?! Now growers will be able douse vast fields of the same crop with the same TWO very toxic herbicides over and over every season, instead of just unlimited amounts of ONE very toxic herbicide over and over every season. Certainly this practice would never ever ever result in multi-resistant weeds, which would then require even MORE genetic tinkering and MORE poisons on food crops, escalating indefinitely with unlimited potential for negative health and environmental impacts.

Ha! Weeds evolving herbicide resistance: what kind of environmentalist wacko would even suggest it?!

What I especially like is how we home gardeners won’t be bothered by all those pesky beneficial insects like bees, butterflies, and ladybugs, since there will be TWICE as much poison around to kill them off. I’m also super excited about how the constant escalation of poisoning our ecosystem guarantees a complete avoidance of anything resembling sustainable agriculture in America, in the foreseeable future. Because, I mean, who’d want that?!


Congratulations, Dow and Monsanto! You have shown the world how to fail at sustainable agriculture, ecology, evolutionary biology, and common sense — all in one fell swoop.

No Steps Up and Two Steps Back

An article recently published in the journal BioScience explores the issue of acquired glyphosate resistance, related to proposed combined-resistance traits in GE food crops.

Authors conclude that ‘stacked resistance’ is likely to simply produce multi-resistant weeds, with continued escalation of herbicide and neglect of agroecological strategies that could provide lasting success in weed management. In other words, at best it’s a high-damage short-term fix, actively undermining development of more sustainable agricultural practices for long-term solutions.

Squeaky Wheels: Report for Duty!

If you’ve watched the USDA’s bad-joke-like nonregulation of GE crops to date, their likely response won’t surprise you. According to reports,

The USDA, for its part, is buying what Dow is selling. Its Draft Environmental Assessment(PDF) offers no critique of Dow’s claims, and recommends that the product be deregulated. The agency is currently seeking public comment on the matter; the comment period ends February 27. Doug Gurian-Sherman, a senior scientist with the Union of Concerned Scientists, told me that when the USDA brings a GMO product to the comment stage after having recommended deregulation, it “almost always” green-lights the product. “The only times I’ve seen the USDA hold off at this stage is when there’s a lot of public pushback,” Gurian-Sherman says.

Ok, public: you heard the man. Push back! Because with stacked resistance to Roundup and 2,4-D, Monsanto and Dow have come up with the very opposite of a good idea.

Image credit: Creative Commons photo by mivanov.


6 thoughts on “New Monsanto-Dow ‘Stacked Resistance’ GE Crops: Big Mistake or Bad Idea?”

  1. Its not that ridiculous really. What produces resistance is more over-reliance than over-use. Let’s just say a weed has a 1/10 chance of having a mutation for glyphosate resistance, and a 1/5 chance of developing a mutation for 2,4-D resistance (the real odds are much lower obviously). If you use both, the chance of resistance to both occurring in the same plant (making one truly resistant to your mix) is the product of the likelihood of the individual events, 10%*20%=2%. For that reason there have been calls for stacked resistance for years. It’s just statistics.

    2,4-D is already used in other crops too I believe, and herbicide resistance is bred into crops conventionally. I wonder why those go unprotested.

    1. The problem is that the push for this continued and indeed expanded reliance on GM agricultural technology is not driven by anything other than the bottom line of companies like Monsanto. This push is then so powerful and dangerous because the duties of those public agencies charged with protecting the food supply and ending hunger have been compromised by conflicts of interest and cash flows. If the public were better informed about the reality of what these corporations are doing and the failure of their institutions to check them the protest would be much greater than we’ve seen so far.

      1. Agreed… Incidentally, Monsanto’s patent on Roundup Ready technology expires in 2014. What a wild coincidence that now they’re sure stacked resistance (a new patent) will solve all the world’s farming problems– that (btw) they themselves created, with Roundup Ready technology! Reality check: *whose* problems will be solved by this shift?! (hint: starts with ‘M’, rhymes with Ron Scranto)

        Yeeeaaaahhhh…. I’m just not buyin’ it (in any sense of the term) as a solution to anything, for anyone but the same folks who created the problem in the first place.

  2. I think one big problem with this one is that it’s *guaranteed* to be massively over-implemented, just like RR crops.

    You’re right, it’s just statistics — but your analysis is oversimplified and incomplete. Each successive generation of weeds in a Roundup-2,4-D resistant corn field is more likely to exhibit resistance to the substances in question than the one before. You speak as though the chance of resistance emergence is a fixed property, and with any population of living things that’s just not how it works. It’s not a static probability ratio, in other words: natural selection ups the odds of resistant traits developing with each passing season, because of living populations’ ability to adapt to environmental pressures.

    Realistically, massive implementation of combined resistance Roundup/ 2,4-D crops (and let’s be honest, that’s what we’re talking about — there’s WAY too much R&D spending to recoup for any other scenario! and too much trouble with RR resistant weeds, from similar strategies already implemented) places the emergence of doubly resistant weeds somewhere on the scale between ‘very likely’ and ‘inevitable’ — just like the glycophosate resistance we’re seeing now, which was initially statistically unlikely.

    Conventional breeding for herbicide resistance doesn’t seem to be gearing up for the same scale of implementation as the brave new multi-resistant GE crops proposed for development. And it’s just the one 2,4-D resistant trait you’re referring to, correct? So in at least two important ways, that’s not really in the same category with the idea under discussion, in terms of generating increased herbicide use or unintended environmental consequences. So, that could be why.

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