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Farmers have begun harvesting a vast crop of genetically modified cotton
that has allowed them to slash the heavy use of pesticides for which they
have long been been criticised, April 2005 by Daniel Lewis.
With NSW and Queensland farmers free for the first time last spring to
plant as much GM cotton as they liked after nine years of caution, about 80
per cent of the 300,000 hectares sown was genetically modified to resist
herbicides and fight the crop's enemy, the helicoverpa moth.
While cotton growers such as Bourke's Ian Cole would normally spray his crop
up to 18 times each growing season to kill off pest insects, this season he
only sprayed three times after choosing to grow a GM crop.
Those three sprays were targeted to attack sucking insects such as mites and
did not wipe out the "beneficials" - spiders, wasps and ladybirds - as the
powerful, broad-spectrum sprays for helicoverpa used to.
"I'm a big believer in technology being able to solve problems for us in
agriculture," Mr Cole said. "Technology has solved a huge problem for us in
Over the years, traditional pesticides had became stronger and were applied
more frequently as insects built immunity.
Helicoverpa moths lay their eggs into the boll, or fruit, of the cotton
plants and when the larvae hatch they eat the fruit.
GM pioneer Monsanto first won permission for Australian farmers to grow its
Ingard GM cotton in 1996.
Ingard contained a gene found in soil bacteria that enabled the cotton to
produce a protein that killed the grubs when they ate the plant.
But because there was a risk of the helicoverpa developing immunity to the
single-gene product, planting of Ingard was limited to 30 per cent.
Now Monsanto has replaced Ingard with Bollgard II, which uses two genes and
produces two deadly proteins. The chance of insects developing immunity to
Bollgard is "extremely small", according to Mark Buckingham, a Monsanto
Ingard enabled farmers to more than halve the amount of pesticide spraying
they needed to do and Bollgard requires 85 per cent less pesticide than
As an ongoing safeguard, farmers planting Bollgard must also plant a "refuge
crop" of pigeon pea.
The theory is that any moths that do develop an immunity to Bollgard would
mate with moths that have fed on the nearby pigeon pea and have not
developed immunity. Their offspring would also not have immunity.
Apart from carnations, cotton is still the only GM crop allowed to be
commercially grown in Australia because of strict government regulations and
strident opposition from environmental and consumer groups.
Mr Cole said that as well as being great for the environment and the
workplace safety of his staff, Bollgard saved farmers a lot of money because
they do not have to spray as much and can devote more time to other matters
such as improving water efficiency. Cotton's thirst for water is the
industry's other public relations problem.
Globally, the area planted with GM crops rose 20 per cent last year to 81
million hectares - 5 per cent of the Earth's cultivated crop land. More than
8 million farmers in 17 countries planted GM crops in 2004 and 90 per cent
were in developing countries. When commercial GM crops were first planted in
1996, there were 1.7 million hectares.
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