THIRD WORLD NETWORK BIOSAFETY INFORMATION SERVICE
Dear Friends and colleagues,
RE: Herbicide Resistant Plants Trigger ‘Arms Race’ Among Chemical Companies
Increasing resistance to herbicides by weeds immune to the chemicals – due largely to the widespread planting of GM herbicide tolerant crops – have triggered a race among chemical companies to develop new GM crops or to use old herbicides to attack the resistant weeds.
The consequences are that farmers could be using more chemicals, some of which are deadlier to the environment than Roundup, to kill more and more ‘superweeds’.
With best wishes,
131 Jalan Macalister,
10400
Email: twnet@po.jaring.my
Website: www.biosafety-info.net and www.twnside.org.sg
Superweed Outbreak Triggers Arms Race
Scott Kilman
http://biolargo.blogspot.com/2010/06/round-up-weed-killer-and-acquired.html
Hardy superweeds immune to the Farm Belt’s most effective weedkiller are invading fields, prompting a counterattack from agribusiness that could leave farmers using greater amounts of harsh old-line herbicides.
The flagging weedkiller is Roundup. Its developer,
The rise of Roundup, more than a decade ago, sent older herbicides that damage both weeds and crops into deep
And big chemical companies-taking a page from
Dow Chemical Co.,
"It will be a very significant opportunity" for chemical companies, says John Jachetta, a scientist at Dow Chemical’s Dow AgroSciences and president of the Weed Science Society of America. "It is a new era."
The bioengineering push is causing controversy, though. Some of the old pesticides-in particular, those called 2,4-D and dicamba-have a history of posing more risks for the environment than the chemical in Roundup. That’s partly because they have more of a tendency to drift on the wind onto neighboring farms or wild vegetation. Roundup tends to adhere better to the ground.
The chemical companies are betting their biotech investments will pay off in two ways: Farmers will buy more of their herbicides, and will pay big premiums for the new seeds.
Some 40% of
The new herbicide-tolerant seeds "would make controlling weeds very easy for farmers," says David Mortensen, a weed scientist at
The burst of efforts by rivals isn’t necessarily bad for
Yet the developments portend further turmoil in the $12 billion
It was back in the 1990s that
The new seeds meant farmers could leave behind the risk and guesswork of choosing the right herbicides to spray, at exactly the right time, on the right weeds. Weed control became so easy that many farmers sold off their weed-tilling implements and stopped buying other pesticides.
The chemical weed control even had some environmental pluses because it left the soil undisturbed, reducing erosion. Farmers burned less fuel, no longer needing to crisscross fields with implements that root out weeds. The Roundup revolution, as some called it, freed up time for growers to plant more land, helping spur bigger farms.
But weeds are adapting. At least nine species have developed immunity to it. They’ve spread to millions of acres in more than 20 states in the
Ron Holthouse, a farmer who grows cotton and soybeans on 8,600 acres near
The weed, which can grow six feet high on a stalk like a baseball bat, is tough enough to damage delicate parts of his cotton-picking equipment. Mr. Holthouse had to hire a crew of 20 laborers to attack the weeds with hoes, resorting to a practice from his father’s generation. For the first time in years, Mr. Holthouse used some of an older, highly poisonous weedkiller called paraquat.
Many Southern farmers are spending twice as much on killing weeds as it typically cost them just a few years ago. "It is getting a lot harder and expensive to run a big farm," says Mr. Holthouse. "This is nerve-racking."
Farmers have no wish to return to labor-intensive methods. The success of expensive seeds that are Roundup-tolerant shows growers will pay a steep premium to control weeds chemically.
Chemical companies are tight-lipped about their development of crops that can tolerate the spraying of herbicides other than Roundup. BASF and Bayer filed petitions last year with biotech regulators at the U.S. Department of Agriculture, seeking permission to market new herbicide-tolerant seeds. The
Dow AgroSciences manufactures 2,4-D, a powerful herbicide introduced nearly 65 years ago. The company hopes by 2013 to be selling seeds for corn crops that will be unaffected if farmers splash 2,4-D on their fields. The company hopes to have seeds for soybeans tolerant of the herbicide a year later, and is also working on a herbicide-tolerant cotton variety.
It won’t predict how the new seeds might help its sales of 2,4-D, but it’s optimistic enough that it’s developing a new form of the herbicide.
Some winery owners are concerned that such efforts will renew farmer demand for 2,4-D, to which grapes are highly sensitive if the herbicide drifts from a farm sprayer onto vines. "I couldn’t survive in this business if 2,4-D resistant seed catches on in cotton country," says Neal Newsom, whose 100-acre vineyard in Plains,
The Natural Resources Defense Council petitioned the Environmental Protection Agency in 2008 to ban 2,4-D, citing research that suggests it disrupts hormones in trout, rodents and sheep. Dow says it is providing rebuttal data to the agency. A spokesman for the EPA said it anticipates responding to the petition this fall.
Both 2,4-D and dicamba, another older herbicide, are common ingredients in weedkillers at lawn-and-garden stores, which homeowners are careful to keep away from flowers and vegetables. Chemical companies say both are safe in larger amounts if farmers follow usage instructions cleared years ago by the EPA.
Allthough dicamba could kill superweeds such as Mr. Holthouse’s pigweed, soybean farmers haven’t sprayed it because it kills soybeans, too. A dicamba-tolerant soybean variety would change that.
Bayer is developing soybeans that can survive exposure to a herbicide that disables weeds’ defense to ultraviolet rays, setting them up for a fatal sunburn. Bayer hopes to have those soybean seeds on the market in 2015 and later give corn and cotton plants immunity to the same herbicide, called isoxaflutole.
As for
Swiss-based Syngenta, meanwhile, is field-testing soybeans genetically engineered to tolerate exposure to a relatively new herbicide Syngenta makes called Callisto.
"The herbicide business used to be good before Roundup nearly wiped it out," says Dan Dyer, head of soybean research and development at Syngenta. "Now it is getting fun again."
Write to Scott Kilman at scott.kilman@wsj.com