The online debate at The Economist Magazine continues. Dont forget to vote.

My rebuttal is here:

I agree with Charles Benbrook that “Bt crops have helped reduce insect feeding damage and lessened the need for toxic, broad-spectrum insecticides, and as a result, helped build populations of beneficial insects and promote above-ground biodiversity, two key sustainable farm-management goals.”

I also wholeheartedly agree with his statements that “Multiple-tactic systems composed of ‘many little hammers’ offer the best hope for sustained progress” and “Biotechnology can help create new hammers and harden existing ones”.

However, he incorrectly implies that GE crops are not being used as part of multiple-tactic systems today.

Bt crops are one of the few examples where a mandatory crop diversity strategy has been implemented. Global pest monitoring data suggest that this approach has helped to sustain the efficacy of Bt crops against most pests for more than a decade. For example, in Arizona, where an integrated pest management programme for Bt cotton is in effect, growers reduced insecticide use by 70% and saved more than $200 million.

Mr Benbrook describes an unlikely hypothetical scenario in which farmers can no longer rely on safe and cheap Bt insecticide sprays because Bt-resistant insects from cotton and corn “routinely overwinter in fruit and vegetable crops”. This has not occurred yet despite more than a decade of use of Bt crops on a cumulative total of more than 200m ha worldwide.

Moreover, while some pests of corn and cotton have evolved resistance to Bt toxins in GE crops, the first cases of insect resistance to Bt toxins occurred in response to spraying Bt insecticides on conventional vegetable crops–an approach favoured by organic farmers, who are not allowed to use transgenics. To help delay resistance, many newer varieties of Bt crops produce two or more Bt toxins with different modes of action.

The bottom line is that strategies for managing pest resistance are needed whether farmers use GE crops or conventional crops.

Contrary to Mr Benbrook’s assertion, Bt crops do promote self-reliance. Although farmers must buy the seed, this is the norm in any non-subsistence farming system where hybrid seed is used (organic and conventional). The advantage is that they do not need to buy and spray insecticides.

Mr Benbrook and I agree that overuse of a single herbicide can lead to the evolution of weeds that are resistant to that herbicide, which is problematic for farmers. Grower decisions to use repeated applications of particular herbicides have led to the evolution of resistant weeds. It is clear that herbicide tolerant (HT) crops need to be managed better for sustainability, rotating them with other crops or weed control methods. But this is also true of herbicide resistance traits developed through selective breeding or mutagenesis.

Mr Benbrook’s argument neglects an important aspect of HT crops that are resistant to the herbicide glyphosate (aka Roundup). Glyphosate (a class IV herbicide) has displaced much more toxic herbicides (classes I, II and III). In Argentina, HT soyabean farmers were able to reduce their use of toxicity class II and III herbicides by 83-100%. In North Carolina, the pesticide leaching was 25% lower in HT cotton fields compared with that of conventional cotton. Thus the main problem with weed resistance in HT fields is that it forces farmers to go back to the more harmful compounds that were in use before the widespread adoption of HT crops.

To mitigate the evolution of weed resistance, the newest HT varieties will have tolerance to more than one herbicide, which will allow easier herbicide rotation or mixing, and, in theory, help to improve the durability of herbicide effectiveness. Implementation of a mandatory crop diversity strategy would also greatly reduce weed resistance. These are also multi-tactic strategies.

Mr Benbrook’s account also does not consider other benefits of HT crops to sustainable agriculture. HT crops have been associated with an increased use of conservation tillage, in particular no-till methods, that can improve water quality and reduce soil erosion. That farmers who use GE crops are more likely to practice conservation tillage suggests the two technologies are complementary.

In Argentina and the United States, the use of HT soyabeans was associated with a 25-58% decrease in the number of tillage operations. Such reduced tillage practices correlate with a significant reduction in greenhouse gas emissions, which, in 2005, was equivalent to removing 4m cars from the roads.

Finally, by limiting the scope of his discussion to only two traits, Mr Benbrook overlooks the benefits of other GE crops on the market. For example, in the early 1990s, Hawaii’s papaya industry was facing disaster because of the deadly papaya ringspot virus (plants, like people, are susceptible to viral infection). The introduction of GE papaya resistant to the disease rescued the state’s papaya industry. Today, 80-90% of Hawaiian papaya is genetically engineered, and there is still no conventional or organic method to control the ringspot virus.

In many regions, the use of biotech seeds allows successful organic production, an important marketing niche, by reducing disease spread, while enabling the remaining 97% of agriculture to become more sustainable by reducing insecticide use. This is true for organic farmers growing cotton in Arizona and papaya in Hawaii as well as for other growers of non-GE seed. Cumulative benefits over 14 years are an estimated $3.2 billion for maize growers in Illinois, Minnesota, and Wisconsin, with more than $2.4 billion of this total accruing to non-Bt maize growers. Comparable estimates for Iowa and Nebraska are $3.6 billion in total, with $1.9 billion for non-Bt maize growers.

Mr Benbrook’s opening statement fails to address the dozens of other useful traits in the pipeline, including nitrogen use efficiency, provitamin A-enriched rice and drought tolerance.

Fourteen years of extensive field studies have demonstrated that genetically engineered crops are tools that, when integrated with optimal management practices, help make farms more sustainable. The vast benefits accrued to farmers, the environment and consumers explain the widespread popularity of the technology in many regions of the world.

Comments

  1. #1 CFD strategies
    November 11, 2010

    Research and test shows that biotechnology have paved way to new kinds of crops. They are high yield and pest resistant. I must say that the effect of biotechnology in our crops are not yet resolved. There is still a long road to take pertaining to it. What we can be comfortable today is that little by little we are solving the problem of our crops sustainability.

  2. #2 dmab
    November 10, 2010

    richarddawkins.net/discussions/543672-inhertitance-of-acquired-behaviour-adaptions-and-brain-gene-expression-in-chickens

    atheists, we’re gonna cut off your heads…

    THE HIGH PRICE OF REVOLUTION
    youtube.com/user/xviolatex?feature=mhum

  3. #3 Ewan R
    November 10, 2010

    If this is true then we should see the honey-bee disaster reverse itself as more roundup is used.

    I don’t quite see how that follows given that afaik no link between herbicide use and colony collapse disorder has even been proposed let alone dispoven (as have proposd links to use of GMs)

    Personally I trust Monsanto about as much as I trust Exxon, and Exxon are funding anti-science climate-change denialism in their bad to stave off any attempt at introducing sustainability for the human race.

    Not sure what this has to do with the price of fish. I trust your opinion on the matter of GMOs as much as I trust Jeffrey Dahmer’s, and he was a serial killer! (does that make you one, or was the last comment just a bit of randomness added for flavor?)

  4. #4 Vince Whirlwind
    November 10, 2010

    Interesting article – I didn’t realise that the GM crops being made “roundup-ready” wasn’t just a cynical means of making farmers buy more pesticide but is rather a way to help farmers substitute for lower impact pesticides.

    If this is true then we should see the honey-bee disaster reverse itself as more roundup is used.

    I guess I will wait and see.

    Personally I trust Monsanto about as much as I trust Exxon, and Exxon are funding anti-science climate-change denialism in their bad to stave off any attempt at introducing sustainability for the human race.

  5. #5 elmlish
    November 9, 2010

    From what I’ve read, which admittedly isn’t nearly enough to be an expert, the field of biotechnology is a field that promises great things and scary disaster scenarios. Now most of those scary scenarios are unlikely and maybe even impossible, but the seemingly cavalier way gmo plants are put into out there into the great wide open with no way of assuring that the plants won’t adversely spread their doctored genes or somehow bollocks up the systems into which their inserted does worry me. I’m more than happy to have those fears assuaged by people more learned than I.
    It just feels analogous to doing research on diseases in the middle of a kindergarten with no safety protocols.

    The benefits you mentioned in the article are really fabulous things and I hope that we continue to get lucky and not roll a critical gmo fumble of any sort. Are my fears similar to those that believe CERN could produce a blackhole and destroy the planet? I hope so!

    Thanks for the article!

  6. #6 mad the swine
    November 9, 2010

    Three words: Deck chairs. Titanic.

    In a few hundred years, Norman Borlaug will be remembered as one of history’s greatest monsters. He created a paradigm that allowed agriculture – temporarily – to feed billions of more people, thus setting the state for human misery on an utterly unprecedented scale when the cheap oil and high technology propping up the ‘Green Revolution’ fails.

    GMO foods are the next generation of this profoundly flawed concept. Even if GMOs can be eaten without negative effects; even if GMOs are more productive than ordinary cultivars; even if GMOs can build beneficial insect populations, replace pesticides, reduce tillage, provide nutrients, and otherwise ‘benefit’ humanity: GMOs are not sustainable, because their existence is predicated on industrial agriculture and the resources of a technocratic society, itself based on cheap and accessible hydrocarbons, that cannot last more than a few generations.

    Please don’t pretend that biotechnology – or organic farming – can ‘feed the world’. Nothing can ‘feed the world’. The only question is whether Gaia’s parasite load will be reduced by deliberate, sensible population controls or by the laws of nature and Malthus. GMOs are a distraction. I refuse to vote on whether the deck chairs should be painted red or green.

  7. #7 Ewan R
    November 9, 2010

    GE crop can cause many bad things to our body.

    No, they can’t, unless you’re envisioning an instance in which you have 10 tonnes of GE crop dropped on your head – compared to their non-GE counterparts GE crops however this statement is entirely fictional.

    For example,we might be allegic to the new crop.

    There are no instances of allergenicity of any GM crop that I’m aware of. Again you’re working within a fictional framework of what GM crops do, which is obviously a useful framework to work from when your assertions have no basis in reality.

    Chemicals used in the modification can be toxic and cancerous, and it already has killed people in the past.

    Really? Which chemicals? To what extent are these chemicals present in the end product rather than in the lab generations away from the final field product – chemicals used during transformation or cloning really have no bearing whatsoever on the safety of the final crop product (unless you’re concerned about the presence of chemicals in homeopathic quantities)

    Using conventional crop can bring great loss of their crop because of insects, but at least it’s better for our body.

    How exactly is it better for out bodies?

    According to your post, farmers are making money more than ever, but I truly think that they will get less money in the futre

    Well… if you truly think it… gotta be true.

    yet more money with conventional crop because it seems like more and more people are perferring organic food

    Conventional != Organic in discussions about agriculture, conventional = high inputs such as pesticides and man-made fertilizer – anathema to purchasers of organic (should be moreso than GMOs, but generally not so much)

  8. #8 Hong-Gyu Lee
    November 9, 2010

    I’m highly against Bt and HT crops, but farmers got to do what they got to do. That’s the hard choice farmers have to make:grow GE crop or conventional crop. Either way, it’s risky and can lose money. GE crop can cause many bad things to our body. For example,we might be allegic to the new crop. Chemicals used in the modification can be toxic and cancerous, and it already has killed people in the past. Using conventional crop can bring great loss of their crop because of insects, but at least it’s better for our body. According to your post, farmers are making money more than ever, but I truly think that they will get less money in the futre, yet more money with conventional crop because it seems like more and more people are perferring organic food, and word is getting out in the media that GMO can be harmful.

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