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RR Crops to Raise the White Flag?
GM Freeze, 19 October 2011
http://www.gmfreeze.org/news-releases/169/
*Superweed spreading "exponentially" in GM cotton - Monsanto tells farmers they
are on their own
Herbicide resistant weeds are winning the pesticide "arms race" in US Roundup
Ready crops, and Monsanto has no intention of shouldering responsibility for
rising weed control costs, according to a new briefing by GM Freeze published
today. [1]
The briefing reports that in the 2010/11 season so far, two new weed species
have become resitant to glyphosate (the active ingredient in Monsanto's
herbicide Roundup used on RR soya maize and cotton), bringing the global total
to 21.
Infestations of superweeds now cover 4.5 million hectares in the US alone. The
noxious weed Palmer Amaranth is spreading "exponentially" in RR cotton according
to Robert Nichols of Cotton Incorporated [2], and once it has reached a certain
size it can only be controlled by hand pulling.
GM Freeze also reports that Monsanto's warranty [3] on the weedkiller does not
cover the failure of the product to control weeds that are now resistant to it:
"Growers must be aware of and proactively manage for glyphosate-resistant weeds
in planning their weed control program. When a weed is known to be resistant to
glyphosate, then a resistant population of that weed is by definition no longer
controlled with labelled rates of glyphosate. Roundup agricultural herbicide
warranties will not cover the failure to control glyphosate-resistant weed
populations."
The severity of glyphosate resistance has forced Monsanto to sign agreements
with other pesticide companies to provide other herbicides to be used in
combination with Roundup. The new approach includes [3]:
*Weedkillers that act in the soil to kill off resistant weeds as soon as they
germinate.
*Roundup and 2,4-D mixtures to burn off weeds in stubble after harvest.
*"Stacked" GM herbicide tolerance genes in seeds to allow spraying with both
Roundup and Dicamba to try to kill resistant weeds in the growing crop. [4]
Dicamba and 2,4-D have been approved for many years, but their overall safety
for people and the environment has been challenged. [5]
RR crops were once marketed as a cheap and simple way to manage weeds in cotton,
soya and maize. Now the rise in glyphosate resistance is cited by at least one
investment adviser in its recommendation to sell Monanto shares.
One US soyabean farmer said recently, "Just spraying Roundup was so easy...There
is no ease anymore."
Other biotech companies, such as Dow and Bayer, are rushing to get their GM
herbicide tolerant crops, using different weedkillers, onto the market to rotate
with them with RR crops to try to prevent or slow the development of weed
resistance.
However growing the same crops with several different herbicide tolerances runs
the risk that the wrong weedkiller could be used and kill the crops as well as
the weeds. To ensure the correct herbicide is used on the right crop, Bayer
suggest marking glyphosate resistant crops with white flags, and others with
green and red flags.
The new industry approaches to controlling weeds in soya, maize and cotton mean
that dependence on glyphosate looks set to continue despite mounting scientific
evidence about its safety for farmers, people, wildlife, the soil and water
supplies. [6]
Commenting Pete Riley of GM Freeze said:
"There is clear evidence that resistant weeds are rampant and winning in RR
crops, and the white flag has been raised on glyphosate!
"The biotech industry seems intent on using more and more chemicals in untested
cocktails to try to control superweeds. The days of cheap and simple weed
control in GM crops are long gone. All farmers are being offered now is more
weedkillers to combine with Roundup or hand pulling. It is clear that Monsanto
has no intention of shouldering any responsibility for the extra costs of the
current weed crisis in their GM crops, and farmers are now paying the price.
"UK farmers should take careful note of what it happening in the US and reflect
on the fact that we would be in a similar position if public opposition to GM
crops had not slowed their introduction. Thankfully we have labels on food to
help us avoid GM, unlike the US where they reject GM but can't always tell what
they are eating.
"What we need in is a different approach to weed control, one we know will work
over time based on longer rotations, crop breaks and crop diversity to avoid
weeds becoming a major problem."
ENDs
Calls to: Pete Riley 07903 341 065
Notes
[1] See GM Freeze briefing Weed Resistance in RR Crops - An update (summary
available)
[2] Nichol R, 2011. "Pigweed Resistance: How much? To what? And where?",
presentation to the Pig Posium organised by the University of Arkansas. See
www.youtube.com/watch?v=T2wTlzixSG8
[3] Monsanto (undated), "Glyphosate Resistant Weed Biotypes". Available at
www.monsanto.com/weedmanagement/Pages/Glyphosate-ResistantWeedBiotypes.aspx
[4] Stacked GM crops contained several GM traits either for different herbicide
tolerant or insect resistance traits. Stacked herbicide tolerant gens enable
mixtures of two or more herbicide to be applied without killing the crop or for
herbicide use to be rotated.
[5] Herbicides are approved individually based on evidence submitted by
companies. Approvals to spray mixtures are based on the individual assessment,
not on data on the toxicology of the whole mixture. Dicamba and 2,4-D are
similar chemicals and were first approved in 1967 and 1940s respectively. Their
approval on safety for health and the environment grounds has been challenged.
See for Dicamba www.pesticide.org/get-the-facts/pesticide-factsheets/factsheets/dicamba
and for 2,4-D http://www.pesticide.org/get-the-facts/pesticide-factsheets/factsheets/24d-factsheet
[6] See GM Freeze/Greenpeace International briefing Herbicide Tolerance and GM
Crops - Why the world should be ready to round up glyphosate
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