Biotech Can Feed World
by Alex and Dennis Avery
The journal Science editorialized on May 23rd that the world is becoming
too
dependent on Roundup-Ready biotech crops. It claimed agriculture had
become
as dependent on glyphosate for weed control as human medicine had become
on
antibiotics. The journal predicted: "There is going to be an epidemic of
glyphosate-resistant weeds."
In the very same issue, however, the University of Nebraska reported
that it
has developed crop tolerance for the herbicide dicamba, adding a new
genetically engineered weed control option to our arsenal. This will
permit
continued expansion of sustainable, low-erosion, high-yield farming
during
the next 40 years of surging world crop demand.
"We can now spray dicamba [a phenoxy herbicide] on a number of different
[crop] plants and have no visible symptoms at all," says Nebraska
molecular
biologist Donald Weeks. He found that dicamba-resistant soybeans could
withstand five times the typical field application of the herbicide.
Dicamba
features a low toxicity-about one-third as high in mice as the organic
pesticide pyrethrum-and low soil persistence.
Giving up herbicides and low-till would lead to more soil erosion,
driving
lower yields and eventually ruining much of the world's cropland.
Conservation tillage has cut soil erosion in crop fields by up to 90
percent
through low-till and no-till farming. Both use herbicides to kill weeds,
rather than relying on traditional plowing. Organic, which bans low
till, is
not a solution. It takes nearly twice as much land to produce a ton of
food
because the fields must produce their own nitrogen as well as the food.
Until now, only the tolerance for the Roundup has been bioengineered
into
crop plants. Roundup kills all weed types, and that's a big reason why
glyphosate-tolerant crops are now being planted on more then 220 million
acres per year, worldwide. They've been the fastest-spreading farm
technology in history.
Nebraska's new dicamba resistance effectively ends the mini-panic over
glyphosate, however. Now, the industry has two effective all-weed
herbicides
that can be bred into crops and rotated-or even stacked in the same
seeds-to
prevent any major resistance. In addition, farmers can also utilize
Bayer's
Liberty-Link, a non-biotech breeding intervention that relies on
gluphosinate and a different mode of action than glyphosate. There are
also
sprayed-on weed killers such as atrazine, which offer low costs and low
environmental impacts, but without the reduced pesticide sprayings of
the
herbicide-tolerant plants.
Even more important, Nebraska's success in finding a disarming gene for
dicamba raises hopes that other disarming genes can be found to provide
tolerance for still more herbicides, thanks to the world's genetic
diversity.
Dicamba tolerance is also a body blow to activist claims that
genetically
engineered crops should be banned. Weeks' creation works through the
plants'
chloroplasts, which means the modified crops can't spread resistance
through
pollen carried by wind or insects. Over time, this will even disarm the
activist claim that biotech crops threaten the plantings of nearby
organic
farmers.
It looks like biotech crops will be with us for the long haul-helping
humanity feed a peak human population of perhaps 9 billion people
without
taking more cropland away from nature.
Dennis Avery is a senior fellow for Hudson Institute in Washington,
D.C.
and is the Director for Center for Global Food Issues. He was formerly a senior analyst for the
Department of State.
Alex Avery is the Director of Research at the
Hudson Institute's Center for Global Food Issues. Readers may write
them at
Post Office Box 202, Churchville, VA 24421.
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