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Agroecology
-- An alternative to herbicides and genetics
by
Rebecca Roberts
November 20, 2000
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The
Green Revolution in agriculture, which began in the 1940's and hit
full swing in the 1960's, employed specific techniques: focusing
on a few key crops, and heavy use of pesticides and chemical fertilizers.
Those techniques successfully averted mass starvation a generation
ago. But now, green revolution practices are threatening the food
supply for future generations. One of the promises of genetically
modified food is that it helps minimize the need for pesticides
and fertilizers, and may help reduce the threat to future food supplies.
But opponents of GM food say that solution poses more problems than
it solves. In the third installment of our series on genetically
modified food, Rebecca Roberts visited a farm where an alternative
is being tested..
***
It's
an unlikely place for a farm -- this vacant lot at a busy intersection
just off the highway east of San Francisco. And it's unusual looking,
too -- no neat rows of uniform vegetables, but several different
plants all mixed in together. Colorful flowers sprout up between
the vegetables. Clover covers the ground. But there's method in
this madness -- and it's the method of Chilean born Miguel Altieri,
a professor of environmental science at the University of California
at Berkeley.
Altieri:
So what we do here, we're doing experiments where we're mixing the
cauliflowers, for example, with fava beans. And fava bean is an
important plant because the fava bean is legume that fixes nitrogen.
So therefore by fixing nitrogen they can connect with the roots
of the broccoli and therefore do a transfer of nitrogen into the
plant and you don't have to use a chemical fertilizer.
It's
called agroecology -- and it's not new; in fact, it's been used
by small farmers for centuries. The premise is that every challenge
in agriculture can be met with a natural, organic solution, instead
of fertilizer, pesticides, or the new kid on the block, genetic
modification. Does your cauliflower need fertilizer to get nitrogen?
Plant it next to fava beans, which trap nitrogen. Is your tomato
crop plagued by aphids? Surround it with cosmos flowers, which attract
hoverflies, whose larvae feed on aphids. Plagued by low yields because
of weeds? Plant clover before your intended crop. There won't be
any room for weeds to grow. But agroecology is hardly a simple approach.
Even Altieri's half-acre plot needs careful and constant attention
from a group of dedicated graduate students.
Altieri:
These systems are a little bit more complicated to manage, they're
more information intensive, and you have to take care of a lot of
the management requirements of the crops. So they're much more information
intensive, rather than input intensive. And many farmers don't have
time for this sort of thing, so they go the easy route, which is
just plant one thing and spray according to instructions and then
you don't have to worry about anything.
You
have to worry about a lot in agroecology, and that may be what keeps
it from being a practical alternative to the promise of genetically
modified seed. For agroecology to work, farmers need accurate information
about the impact of planting one crop next to another. With GM seed,
you simply buy it and plant it. Richard Manning, author of "Food's
Frontier, the Next Green Revolution", describes how local biologists
in India developed a genetically modified chickpea, a major source
of protein in the subcontinent.
Manning:
The biggest problem, the reason that the average Indian has about
a third of protein he ought to have is that there's an insect that
attacks their chickpeas. So these three middle aged women, figured
out a way to take a gene from windbean, that confers a natural resistance
to that insect. And they put it into that, and then they distribute
the seed free to the people in their country. And that will increase
the protein content and decrease reliance on insecticides. I really
can't find a downside to that.
Manning
considers himself an environmentalist, and began the research on
his book expecting to disagree with GM food as a solution to the
negative aspects of the green revolution. But the more he studied
it, he says, the more he began to see GM as a practical alternative.
Manning:
Agriculture is probably the greatest environmental damage that we
do on the planet. And that's been true for ten thousand years. We've
done incredible damage with green revolution technologies like chemical
fertilizers, like pesticides, like irrigation. And so in that context,
if we can view some limited public interest genetic engineering
as a way to take the hard edge off those other technologies, then
I think it's appropriate.
Miguel
Altieri disagrees. Not only do genetically modified crops pose unforeseen
environmental threats, he says, but over time GM can squelch any
alternative farming methods.
Altieri:
On the one side you have contamination with pollen for organic farmers,
which is a problem. But then the other problem is that when the
insects are exposed to that toxin become resistant, then those resistant
insects will move to organic farmers fields, and organic farmers
will not be able to control them.
The
growing use of GM seed is obvious even at Miguel Altieri's experimental
farm. He shares his land with a genetically modified corn project
funded by biotech giant Novartis. Last year, anti-GM protesters
destroyed the corn crop, but left Altieri's agroecology experiments
untouched. This year, the high tech corn crop is protected by guards
and security cameras. Altieri worries that the pollen from the GM
corn may contaminate his experiments. But on a larger scale, he's
concerned that in the rush to embrace new technologies, traditional
farming techniques will be lost.
Altieri:
Unfortunately today I think that modern scientists look at traditional
farmers as ignorant and people that don't have much idea. I think
that that attitude is very wrong. Because the key to developing
sustainable farming systems for the third world lies in the indigenous
systems that unfortunately modernity is destroying. And we need
to rescue that knowledge very very quickly before it's lost.
And
that's what Altieri is trying to do. He has no illusions that he's
going to transform modern agriculture as we know it -- instead he
works with non-governmental organizations to teach his techniques
to struggling farmers in the developing world. His current project
is in the Dominican Republic, where he's sharing techniques for
controlling soil erosion during hurricane season. For the World,
I'm Rebecca Roberts.
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