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2-Plants: Agronomic problems with transgenic crops: a summary

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TITLE:  Agronomic problems with transgenic crops: a summary
DATE:   May 25, 1999

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The 'fact' that GM crops are good news in terms of food
production (in quantative terms at least) is constantly repeated
in the media and elsewhere. It appears an entirely sensible
assumption given the apparent enthusiasm of so many farmers for
growing them. The reality, as independent research increasingly
demonstrates, is very different (eg see

Recently we posted an important article ( "The EmperorŒs
Transgenic New Clothes") by UK land agent Mark Grifiths> which detailed the agronomic problems,
particularly as regards yield, with transgenic crops and
explained how these problems are being successfully hidden in the
US. As the article was quite long, we thought we would provide a
simple summary which also draws on additional evidence (available
on the Farming News page of the ngin website). Any inaccuracies
are, of course, entirely are own (see Mark's original article on
the ngin website: .

Agronomic problems with transgenic crops: a summary

* Millions of acres of transgenic crops are already being
  planted, with US farmers in the vanguard. The independent
  evidence currently available, however, does not seem to support
  the much advertised claim that transgenic varieties are
  improving crop performance or boosting farmers' incomes.

* Some notable agronomic failures have occurred, perhaps most
  spectacularly the crop failure of thousands of acres of
  genetically modified (GM) cotton in Mississippi in 1997.

* Management problems have included the US Environmental
  Protection Agency's insistence that crops modified with the
  insect-resistant Bt toxin be planted only on part of a farmer’s
  corn or cotton acreage because of concern about a build up of
  pest resistance.

* Other agronomic failures have been more subtle and US famers
  appear largely unaware of their prevalence.

* This is probably because transgenic varieties are bypassing
  traditional independent testing procedures, making it difficult
  for farmers to obtain unbiased advice and information on their
  performance relative to unmodified varieties, leaving the
  biotechnology companies free to proclaim thieir virtues.

* Traditionally when companies in the US introduce a new variety,
  Extension crop specialists (university scientists who advise
  farmers) field test the new variety for at least 3 to 5 years.

* With GM crops, the companies are going directly to the farmers
  with contracts, and the Extension crop specialist is being

* This means the vast majority of GM performance data is held by
  the biotechnology companies. When data is released it is
  usually in the form of summaries where unreleased raw data has
  been analysed and interpreted by the companies themselves and
  not by independent agronomists.

* Where independent scientists undertake such work and the
  results are published, it is not always made clear whether
  particular crops are transgenic or otherwise, as the
  agronomists are not always provided with this information by
  the companies.

* However, research publicised in 1998 by the University of
  Arkansas and Cyanamid appeared to show reduced profit levels
  and lower yields for GM soya and cotton compared with
  unmodified varieties. According to Cyanamid, trials on nearly
  300 test sites across the US showed that high performing non
  modified varieties produced yields up to 20% more than
  transgenic soya in 1997.

* Cyanamid is a commercially interested party, but it is
  possible to track down some independent data on comparative
  yields and this appears broadly supportive of the Cyanamid

* The University of Purdue (1997) found trangenic soya varieties
  yielded on average between 12% and 20% less than
  unmodified varieties grown at the same locations.

* In listings published by the University of Arkansas (based on
  the 1998 harvest), the top performing Soya varieties in terms
  of yield were almost invariably non-modified varieties.

* A University of Wisconsin study (1999) of soya yields at 21
  trial locations across 9 Northern US states, found lower yields
  from GM soya compared with non-GM varieties in the 1998 harvest
  at all but 4 of the trial locations (see attached chart).
  Details of this research can be viewed via

* Independent trials with GM crops in the UK show the same
  pattern. Trials run by UK's National Institute of Agricultural
  Botany (NIAB) in 1997 and 1998 showed yields from GM winter
  oilseed rape and sugar beet were between 5-8% less than high
  yielding conventional varieties.
  reported Farmers Weekly (UK), 4th December 1998

* Not surprisingly a number of US agronomists are quietly
  advising farmers that if they are considering changing from
  traditional varieties for economic reasons they need to
  approach the question of the performance of transgenic
  varieties with great care.

* This loss of yield with GM crops needs to be seen in the
  context of the increased costs that the technology imposes. For
  example, with Roundup Ready soya farmers have to pay the extra
  "technology charge" to use the GM crop in the first place and
  on top of this, as Charles Benbrook has pointed out, farmers
  are finding they need to apply 2-3 applications (not just one
  as Monsanto advertises) of Roundup - expensive! Benbrook says 2
  or 3 other herbicides may also need to be applied. All of
  whichmakes "for the most expensive soybean seed-plus-weed
  management system in modern history"
  Synthesis/Regeneration 19, Spring 1999 p. 15

* However, biotechnology companies are in a position to obscure
  the agronomic realities. As they continue to puchase
  traditional seed houses, they are increasingly in a position to
  phase out existing non-modified varieties, irrespective of
  their merits, or slow their development.

* Biotechnology giant Novartis has already threatened to withdraw
  the supply of non-GM sugar beet seed to the Republic of Ireland
  in the face of resistance to the development of GM varieties,
  warning that: "Given the importance of Novartis on the Irish
  market, this would have serious implications for the Irish
  sugar beet industry." For more on this see

* The fundamental question is: given the extent of uncertainties
  about the marketability, environmental safety and human health
  risks of GM crops, are the risks involved worth taking for what
  appear to be marginal or non-existent benefits?

* Additionally, in the light of the actual evidence, what are we
  to make of the biotech industry's claims that the rapid
  introduction of this technology is a necessity in order to
  'feed the world'?

For more information see the Farming News page on the ngin

For detailed information and great links on the poor agronomic
performance of GM crops visit:


-| Hartmut Meyer
-| Co-ordinator
-| The European NGO Network on Genetic Engineering
-| Reinhaeuser Landstr. 51
-| D - 37083 Goettingen
-| Germany
-| phone: #49-551-7700027
-| fax  : #49-551-7701672
-| email:

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