Exposed: The
Great GM Crops Myth
By Geoffrey Lean
Published in The UK Independent
(April 20, 2008)
Genetic modification actually cuts the productivity of crops, an authoritative
new study shows, undermining repeated claims that a switch to the
controversial technology is needed to solve the growing world food
crisis.
 The study - carried out over the past three years at theUniversity
of Kansas in the US grain belt - has found that GM soya produces about
10 per cent less food than its conventional equivalent, contradicting
assertions by advocates of the technology that it increases yields.
Professor Barney Gordon, of the university’s department of agronomy,
said he started the research - reported in the journal Better Crops
- because many farmers who had changed over to the GM crop had “noticed
that yields are not as high as expected even under optimal conditions'.
He added: “People were asking the question ‘how come I
don’t get as high a yield as I used to?’'
He grew a Monsanto GM soybean and an almost identical conventional variety
in the same field. The modified crop produced only 70 bushels of grain
per acre, compared with 77 bushels from the non-GM one.
The GM crop - engineered to resist Monsanto's own weedkiller,
Roundup - recovered only when he added extra manganese, leading
to suggestions that the modification hindered the crop’s
take-up of the essential element from the soil. Even with the
addition it brought the GM soya's yield to equal that of the
conventional one, rather than surpassing it.
The new study confirms earlier research at the University of Nebraska,
which found that another Monsanto GM soya produced 6 per cent less
than its closest conventional relative, and 11 per cent less than
the best non-GM soya available.
The Nebraska study suggested that two factors are at work. First,
it takes time to modify a plant and, while this is being done,
better conventional ones are being developed. This is acknowledged
even by the fervently pro-GM US Department of Agriculture, which
has admitted that the time lag could lead to a “decrease'
in yields.
But the fact that GM crops did worse than their near-identical non-GM
counterparts suggest that a second factor is also at work, and that
the very process of modification depresses productivity. The new Kansas
study both confirms this and suggests how it is happening.
A similar situation seems to have happened with GM cotton in the US,
where the total US crop declined even as GM technology took over.
(See graphic above.)
Monsanto said yesterday that it was surprised by the extent of the decline
found by the Kansas study, but not by the fact that the yields had
dropped. It said that the soya had not been engineered to increase
yields, and that it was now developing one that would.
Critics doubt whether the company will achieve this, saying that it
requires more complex modification. And Lester Brown, president of
the Earth Policy Institute in Washington - and who was one of the
first to predict the current food crisis - said that the physiology
of plants was now reaching the limits of the productivity that could
be achieved.
A former champion crop grower himself, he drew the comparison with human
runners. Since Roger Bannister ran the first four-minute mile more
than 50 years ago, the best time has improved only modestly . 'Despite
all the advances in training, no one contemplates a three-minute mile.'
Last week the biggest study of its kind ever conducted - the International
Assessment of Agricultural Science and Technology for Development
- concluded that GM was not the answer to world hunger.
Professor Bob Watson, the director of the study and chief scientist
at the Department for Environment, Food and Rural Affairs, when asked
if GM could solve world hunger, said: “The simple answer is
no.' |
