Genetically-Manipulated Crops Prove to Have Reduced Yields According to Independent Research
Monsanto Investing News web page.
For years, biotechnology companies and government beaurocrats have been
telling farmers and others that genetically-manipulated crops can increase
crop yields. Independent research now shows that not only is this not true,
but crop yields from many genetically-manipulated crops is worse than that
of normal crops.
- 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
- 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).
- 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.
- 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.
- 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.
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].
For more information see the Farming News page on the ngin website:
For detailed information and great links on the poor agronomic
performance of GM crops visit: