Monsanto's superweeds & superbugs
Marcia Ishii-Eiteman
Ground Truth, 8 September 2011
http://www.panna.org/blog/monsantos-superweeds-superbugs
The ecological, economic and agronomic disaster accompanying herbicide-tolerant
transgenic crops is by now well known: over 10 million acres of superweeds
resistant to Monsanto's weedkiller, RoundUp; farm machinery breaking on
RoundUp-resistant pigweed thick as a baseball bat; Monsanto paying farmers to
spray their fields with competitors' herbicides; a new generation of transgenic
crops in the pipeline engineered to withstand older even more dangerous
chemicals like 2,4-D.
Last week brought more bad news for Monsanto: the same phenomenon is also
occurring in insect pest populations that are developing resistance to
transgenic "Bt corn" in the Midwest. The Wall Street Journal recently reported
Iowa State University's findings that the corn rootworm is for the first time
proving resistant to the insecticidal toxin, Bt, in transgenic corn in Iowa.
Four days later, Business Week reported Bt corn plants in northwestern Illinois
toppling over after root damage caused by the same insect, apparently as
impervious as its Iowa cousins to the engineered Bt toxin. Likewise, insect
resistance to transgenic Bt crops in India (where dramatic crop failures
resulted) and South Africa has been reported.
http://indiatoday.intoday.in/story/Bt+cotton+has+failed+admits+Monsanto/1/86939.html
http://www.bioone.org/doi/abs/10.1603/EN09220
This is a classic case of the pesticide treadmill. A pesticide application
(whether sprayed the old-fashioned way or applied through a crop plant
engineered to contain that toxin in its cells) typically kills many - but not
all - of the targeted pests. Of those that survive, some will pass on their
genetic traits of pesticide resistance to their offspring, gradually leading to
a more and more resistant population. Farmers get trapped on this treadmill as
they are forced to use more - and increasingly toxic - chemicals to control pest
populations that continue to develop resistance to each new type or class of
pesticides.
http://panna.org/issues/pesticides-101-primer#2
Ecological unravelling
The fundamental unsustainability of chemically-depedendent ag doesn't end with
the emergence of superbugs. By eliminating one pest (even if only temporarily),
Bt crops increase their vulnerability to other "secondary" pests that can
quickly fill the ecological niche and become serious pests in their own right.
In the Makathini Flats of South Africa, farmers have resorted to using large
amounts of acutely toxic organophosphates to control secondary pests that have
emerged (aphids, jassids, thrips and true bugs). In China, Bt cotton has not
only provided a safe haven but also become a source of mirid bugs that then
infest other crops such as grapes, peaches, pears and apples.
Organic farmers have used the naturally occurring form of Bt (a soil bacterium)
successfully for over 40 years as part of organic pest management. Because it
breaks down in sunlight, selection pressure is low and insects have been slow to
evolve resistance to it. Until now. The impending loss of Bt as an effective
tool of the organic farmer adds insult to an already injurious system.
It's called 'planned obsolescence'
The worst part about the latest GE fiasco is that it all could have been
prevented. As early as 1993, scientists were warning about the inevitable rise
of superweeds and superbugs. Ten years later, EPA sought scientific advice on
how to manage the likely emergence of insect resistance to Bt crops. The Center
for Food Safety's Bill Freese describes how a majority of the scientists
consulted by EPA at the time urged the EPA to require farmers to set aside a
refuge of non-GE corn, comprising 50% of the total crop acreage, in order to
slow the development of Bt resistance.
http://online.wsj.com/article/SB10001424053111904009304576532742267732046.html#articleTabs%3Dcomments
But that would have halved Monsanto's seed sales! So EPA quietly sided instead
with the only three dissenting voices in the group, going along with Monsanto's
recommendation for a much smaller 20% refuge.
http://www.nature.com/nature/journal/v422/n6927/full/422005a.html
From industry's perspective, the emergence of pesticide resistance, secondary
pests and failure of first generation GE crops is actually good business;
farmers will have to keep coming back for stronger poisons and more expensive
products. There's an industry term for this: planned obsolescence.
Fortunately, as Doug Gurian-Sherman of the Union of Concerned Scientists reminds
us, plenty of non-GE solutions to corn rootworm exist. These solutions lie in
agroecological practices such as long crop rotations, biological control and
good soil management.
http://blog.ucsusa.org/engineered-pest-problems
It's not too late for us to get off the pesticide/GE treadmill; but we will have
to give our public agencies a big shove to get them moving in the right
direction.
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