-
> Roundup-resistant weeds are cropping up
> The herbicide is so popular that it
> may not be as effective as it was initially.
> By PHILIP BRASHER
> Register Washington Bureau
> 01/10/2003
>
>
>
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> Washington, D.C. - Few inventions have
> altered agriculture recently as much as Roundup
> weedkiller, but now scientists are concerned that
> farmers are using the herbicide so heavily it is
> losing its effectiveness against some of the world's
> peskiest weeds.
>
> "It's going to happen. It's inevitable,"
> said Bob Hartzler, a weed scientist at Iowa State
> University.
>
> Known generically as glyphosate, Roundup
> is powerful yet environmentally benign. It has led
> to the widespread adoption of soil-saving techniques
> that reduce land erosion and combat global warming.
> Even home gardeners are likely to have a version of
> Roundup in their garage arsenal.
>
> Roundup has been around for nearly 30
> years but exploded in popularity in the late 1990s
> with the development of genetically engineered
> soybeans, cotton and other crops that are immune to
> the herbicide. That change means farmers can spray
> their fields with the relatively cheap weedkiller
> whenever it's needed with no fear it will harm the
> crops.
>
> Roundup-immune soybeans now account for
> 75 percent of all the soybeans planted nationwide
> and in Iowa. Some 33 million pounds of glyphosate
> were sprayed on soybean crops alone in 2001, a
> five-fold increase from 1995, according to the U.S.
> Department of Agriculture.
>
> Scientists are finding Roundup-resistant
> weeds in a variety of states, from Iowa to Delaware.
> Scientists are so concerned that some 200 showed up
> for a symposium on the issue last month in St.
> Louis.
>
> Monsanto Co., which invented both
> Roundup and the Roundup-immune crops, has applied to
> the Environmental Protection Agency to alter Roundup
> labels to add special instructions for farmers in
> areas with resistant weeds.
>
> A rival manufacturer of glyphosate,
> Syngenta, is advising farmers not to apply the
> chemical more than twice in every two-year period
> and not to plant glyphosate-resistant crops in the
> same field every year.
>
> "The warning signs are already out
> there," said economist Charles Benbrook, a critic of
> the biotech industry and a former executive director
> of the National Academy of Sciences" board on
> agriculture.
>
> If herbicide-tolerant weeds gain hold,
> land prices could slip and farmers would be forced
> to start using additional chemicals, adding to their
> costs and potentially increasing environmental
> risks.
>
> No alternatives to Roundup are on the
> horizon. Industry experts say Roundup has been so
> effective for so long that there has been no
> financial incentive for chemical companies to
> develop a substitute.
>
> Farmers love the bioengineered soybeans
> because they say Roundup makes it easier and cheaper
> to control the weeds. Ron Heck of Perry, Ia., says
> he used to spend $20 to $40 an acre on weed control.
> Now the cost is down to about $15 an acre, even
> accounting for the special fee for the seed.
>
> Growers also say the biotech soybeans
> have allowed them to farm more land and spend more
> time with their families, or in some cases take a
> second job.
>
> Monsanto throws in some more incentives:
> If the biotech crops fail, the company will refund
> some of the seed cost. And if the herbicide doesn't
> kill the weeds, farmers can get additional Roundup
> for free.
>
> Roundup is so effective as a herbicide
> that many farmers are no longer tilling their fields
> to control weeds. Less tillage means less erosion
> and stores carbon in the soil, thereby limiting the
> production of the greenhouse gases blamed for global
> warming. No-till soybean acreage increased by 35
> percent from 1995 to 2000, according to one study.
>
> Herbicide resistance in weeds is nothing
> new. It happens regularly with weedkillers, except,
> until recently, with Roundup.
>
> Some of the first significant reports of
> Roundup-resistant weeds in the United States
> surfaced in Delaware. Mare's-tail, or horseweed,
> that could not be killed by the herbicide was found
> on several farms in 2000. Scientists said they had
> to spray the weeds with 10 times the recommended
> rate of the herbicide to kill the plants.
>
> Scientists in Iowa and Missouri have
> found fields with types of waterhemp, a prolific
> Midwestern weed, that are significantly more
> tolerant of glyphosate than others. More than a
> quarter of the weeds collected from one Iowa field
> survived being treated with Roundup.
>
> The scientists say it remains to be seen
> how quickly the hardier weeds will spread.
>
> "Everybody is in reasonable agreement
> that the evolution of glyphosate resistance in
> waterhemp is inevitable," said ISU scientist Mike
> Owen.
>
> Monsanto, which generates 50 percent of
> its annual sales from Roundup, says there are two
> U.S. weeds that are resistant to it - mare's-tail
> and ryegrass - but company officials say the problem
> isn't serious. They don't consider waterhemp
> resistant.
>
> David Heering, who manages the technical
> side of the Roundup business for Monsanto, said
> rival companies like Syngenta are trying to
> discourage farmers from using the
> glyphosate-resistant, or Roundup Ready, crops
> because they cut into sales of other herbicides. "As
> we see increased adoption of Roundup Ready, they are
> going see lost business," Heering said.
>
> Chemical companies have another reason
> to discourage use of Roundup Ready crops: Monsanto
> profits from the special technology fee it charges
> on every bag of the gene-altered seed. Other
> companies do not.
>
> Syngenta officials say they are trying
> to ensure that glyphosate, which they market as
> Touchdown, remains effective.
>
> In Iowa, farmers typically don't plant
> soybeans in the same field two years in a row, as
> some Eastern growers do, so there is less chance of
> overusing the herbicide. But some farmers are
> considering growing Roundup Ready corn in addition
> to Roundup Ready soybeans, and that could increase
> use of the weedkiller and speed up the spread of
> resistant weeds, some scientists say.
>
>
> More about Roundup
>
> Roundup herbicide, introduced by
> Monsanto Co. in 1974, works by interfering with a
> key enzyme in plants and preventing then from making
> essential amino acids. People and animals don't have
> the enzyme, making the chemical relatively safer
> than many other pesticides.
>
>
> POPULARITY: Use of Roundup, known
> generically as glyphosate, exploded when Monsanto
> scientists figured out how to make crops immune to
> it by inserting into them a soil bacterium gene. The
> bacterium contains an enzyme similar to the one that
> plants naturally have. The biotech crops accounted
> for about 75 percent of the soybeans, 50 percent of
> the cotton and 10 percent of the corn planted by
> U.S. farmers last year.
>
> FRIENDLY: Roundup also is widely used by
> homeowners and along roads and railways. Glyphosate
> is considered so environmentally friendly that it is
> used to control weeds on the ecologically unique
> Galapagos Islands.
>
> AWARDS: The Monsanto scientist who first
> identified the herbicidal activity in glyphosate was
> awarded the National Medal of Technology in 1987. In
> 1994, Farm Chemicals magazine called Roundup one of
> the top 10 products that "changed the face of
> agriculture."
>
>
>
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