Genetically modified crops shrink farming’s pesticide footprint

Image: Genetically modified insect protected cotton on the left, next to a closely related conventional cotton variety on the right which is showing the damage from heavy insect feeding pressure. Greg Kauter, Courtesy of Australian Cotton Growers Research Association Inc, Narrabri, NSW.

There is a concise summary of the benefits of modern agriculture at The Conversation, by University of Melbourne scientists Richard Roush, and David Tribe:.

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Recent news reports claim one in ten Australians believe the world will end on December 21, 2012, based largely on internet gossip about the meaning of ancient stone carvings from the Mayans of Central America. Such is the disturbing power of frightening myths to influence human belief.

No wonder modern apocalyptic mythology about agriculture, sinister stories about pesticides and assertions that genetic engineering of crops break a biological taboo find a very receptive audience, especially among those who don’t ever go to a modern farm.

In truth, there’s a lot to feel good about in the way modern agriculture is shaping up to the big challenges of the present – reducing carbon emissions, preventing soil erosion and minimising any environmental damage by herbicides and pesticides.

Helping the environment

One of the most significant crop management improvements in recent times has been the increasingly common practice of sowing seeds by direct drilling them into the stubble of the previous season’s crop. This approach forgoes a massive amount of soil tillage with the plough. Such minimum-tillage or no-tillage farming means that much less diesel oil is used in tractors and carbon levels can buildup in the soil rather than be released to the atmosphere.

It’s been estimated that the carbon emission savings from introduction of genetically engineered crops that encourage no-till farming are equivalent to removing 19.4 bn kilogram of carbon dioxide from the atmosphere worldwide. This is equal to the carbon emissions savings from removing 8.6 million cars from the road for one year.

Minimal tillage farming also has several other benefits, such as better moisture retention in the soil and reduction in soil erosion.

Modern crop genetic engineering has provided farmers with much better crop variety options for use in no-till farming. One of these is crops that are tolerant of the herbicide glyphosate. This is the most widely used types of GM crop. Glyphosate-tolerant crops include soya beans, canola, cotton and maize. Glyphosate has much lower environmental impact than chemicals such atrazine, which it replaces. Unlike atrazine, which is banned in the European Union, glyphosate is relatively rapidly degraded in the soil and does not easily leach into water run-off to river basins.

(…) Hopefully, readers will realise that most of the sinister prophesies circulating about  crop genetic engineering are as useful as the current myth that Mayan hieroglyphics say the world will end in December.

The authors were careful to head off the usual “corporate shill” comments by their complete transparency:

Richard Roush receives research funding from the Grains Research and Development Corporation.

Rick Roush has advised the US EPA on resistance management issues twice in the last 4 years. The US EPA requires a formal disclosure review process to identify any possible conflicts of interest, which Rick has passed. Rick does not work for, consult for, own shares in or receive funding from any private company that would benefit from this article, and has no relevant affiliations.

David Tribe does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article except the University of Melbourne, where he is paid for teaching research and community outreach by a standard salary arrangement with the University. He has no relevant affiliations that might entail a conflict of interest in scientific analysis.