Healthy soil and sustainable growing

["TradingPostPaul" <tradingpost@riseup.net>]

Published on Thursday, July 27, 2006 by the Independent/UK
Farmers Use as Much Pesticide With GM Crops, US Study Finds
by Steve Connor
http://news.independent.co.uk/

One of the major arguments in favour of growing GM crops has been
undermined by a study showing that the benefits are short-lived because
farmers quickly resort to spraying their fields with harmful pesticides.

Supporters of genetically modified crops claim the technique saves money
and provides environmental benefits because farmers need to spray their
fields fewer times with chemicals.

However, a detailed survey of 481 cotton growers in China found that,
although they did use fewer pesticides in the first few years of adopting
GM plants, after seven years they had to use just as much pesticide as they
did with conventional crops.

The study found that after three years, the GM farmers had cut pesticide
use by 70 per cent and were earning over a third more than conventional
farmers.

But, by 2004, the GM cotton farmers were using just as much pesticide as
their conventional counterparts and were spending far more because GM
cotton seed is three times the price of conventional cotton seed.

The findings will undermine claims by the biotechnology industry that GM
technology can boost food production without necessarily damaging the
environment with pesticides.

Scientists from Cornell University in Ithaca, New York, carried out the
study which involved interviews with hundreds of Chinese farmers who had
switched to cotton that had been genetically modified with a gene for a
bacterial toxin.

The toxin - known as Bt - is secreted by the GM cotton plant and is highly
effective at stopping the growth of bollworm, a major pest of the crop that
can cause millions of pounds worth of damage.

Major cotton producers, the United States, China, India and Argentina,
quickly adopted Bt cotton after it was introduced in 1996 by Monsanto, the
American biotechnology company.

Today, more than a third of the global cultivation of cotton is accounted
for by Bt cotton, ranging from 42.8 million hectares in the United States
to 3.7 million hectares in China.

Before the introduction of the GM crop into China, farmers in the country
had to spray on average 20 times each growing season to control bollworm
but, with Bt cotton, the average number of treatments fell to below seven.

The amount of pesticide also fell by 43.3kg per hectare in 1999, which was
a decrease of about 71 per cent on previous years.

However, Professor Per Pinstrup-Andersen and his colleagues at Cornell
found that all those benefits have since been largely lost due to the rise
of other pests that were not considered a problem for cotton.

"Using a household survey from 2004, seven years after the initial
commercialisation of Bt cotton in China, we show that total pesticide
expenditure for Bt cotton farmers in China is nearly equal to that of their
conventional counterparts," the scientists say in their report.

"Bt farmers in 2004 on the average have to spray pesticide 18.22 times,
which is more than three times higher compared with 1999.

"Detailed information on pesticide expenditures reveals that, though Bt
farmers saved 46 per cent of bollworm pesticide relative to non-Bt farmers,
they spend 40 per cent more on pesticides designed to kill an emerging
secondary pest," they say.

Secondary pests, such as a type of leaf bug called mirids, are not normally
a problem in cotton fields because bollworm, and sprays against bollworm,
tend to keep them in check.

However, because Bt cotton is targeted mainly against bollworm, other pests
are able to exploit the relatively low use of pesticide that such fields
need.

"These results should send a very strong signal to researchers and
governments that they need to come up with remedial actions for the
Bt-cotton farmers, otherwise these farmers will stop using Bt cotton and
that would be very unfortunate," Professor Pinstrup-Andersen said.

© 2006 The Independent