A major study of genetically-modified crops has just been released by the US National Academy of Science’s National Research Council. The report is described as “the first comprehensive assessment of the impact of genetically modified crops on American farmers.”

Chief benefits cited related to diminished use of especially harmful herbicides, increased use of no-till farming (which curtails soil erosion and rainwater run-off), and farmer productivity.

However, downsides, especially looking to the future, were also noted, with the report saying “overuse” threatens gains.

As reported by the NY Times:

“The report found that the crops allowed farmers to either reduce chemical spraying or to use less harmful chemicals. The crops also had lower production costs, higher output or extra convenience, benefits that generally outweighed the higher costs of the engineered seeds.”

But, said the Times, the chairman of the report team “warned that farmers were jeopardizing the benefits by planting too many so-called Roundup Ready crops. These crops are genetically engineered to be impervious to the herbicide Roundup, allowing farmers to spray the chemical to kill weeds while leaving the crops unscathed.

“Overuse of this seductively simple approach to weed control is starting to backfire. Use of Roundup, or its generic equivalent, glyphosate, has skyrocketed to the point that weeds are rapidly becoming resistant to the chemical. That is rendering the technology less useful, requiring farmers to start using additional herbicides, some of them more toxic than glyphosate.”

More than 80 percent of the corn, soybean and cotton grown in the United States is genetically engineered. The crops tolerate Roundup, are resistant to insects, or both.

The Times article is comprehensive in reporting a full range of opinions about GE cropping. Well-worth a read.

The full report, as well as an executive summary and Powerpoint presentation, can be downloaded here.

Tom Belford

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  1. http://www.i-sis.org.uk/AfterMonsantoGMcropsmeltd
    One major impact of crops genetically modified (GM) for insect resistance is that the Bacillus thuringiensis (Bt) Cry toxins conferring insect resistance are specific for particular pests. After the Bt crops have been planted for several years, the target pest is usually diminished, leaving an ecological niche into which another insect pest species may invade. This has already happened with Bt cotton in India [1] (Mealy Bug Plagues Bt Cotton in India and Pakistan, SiS 45) and in the United Stated, where the tarnished plant bug has emerged as the major pest in the cotton belt [2] (GM Crops Facing Meltdown in the USA, SiS 46).

  2. Which will of course also happen with bacillus subtilis, that new found 'organic' orcharding bacteria that effervesces in the lungs, contaminates the waterways … mind you in that respect our councils can hide behind the international literature on those low socio-economic areas.

    When the Regional Council permitted the off site drift of toxic sprays (lime sulfur plus bacteria) on such a grand scale, they condemned the area to experiencing the worst health effects of any area in New Zealand … respiratory problems plus all those other ailments (cancers) that can be attributed to PM 2.5s, which of course they do not measure.

    Nice that there is no pesticide residue on the fruit, abominable that this is achieved by toxic aerosol that drifts offsite & can strip the paint off your car … & the soft tissue of your kids … eyes, throat, upper respiratory tract … just for starters.

    It is this issue that should be paramount, should be at the forefront of our local body elections … it is tantamount to a cavalier disregard for public health.

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