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Maternal Health: A New Study Challenges Benefits of Vitamin A for Women and Babies
By DONALD G. McNEIL Jr., The New York Times, May 3, 2010
Giving women vitamin A capsules did not save their lives or the lives of their new babies, according to a surprising new study from Ghana reported this week by the medical journal Lancet.
The results contradicted an earlier study in Nepal that showed a huge drop in deaths among child-bearing women taking vitamin A, and disappointed experts who hoped pills could be a cheap, easy lifesaver. Scientists did establish in the 1980s that giving vitamin A to malnourished children prevented stunting and deaths from measles and diarrhea.
The 1999 study in Nepal suggested the vitamin also saved young mothers, although that result was regarded somewhat skeptically because so many of the women had died of unrelated causes, including burns, drowning, snakebite and hanging.
Writing in a Lancet commentary, Anthony Costello and David Osrin of the global health institute of University College London noted that the new study recruited an “astonishing” number of women — nearly 208,000 in more than 1,000 villages or family compounds.
Half got a weekly low dose of vitamin A, and half got a placebo. Few in either group died, but the vitamin also did not reduce hospitalization for childbirth complications. Nor did it reduce stillbirths or deaths of newborns. Recent trials in Bangladesh and Indonesia had similar results.
Finding ways to get more food to young women might be more effective than getting them vitamin pills, the commentary’s authors said.
Mammoth Hemoglobin Offers More Clues to Its Arctic Evolution
By NICHOLAS WADE, The New York Times, May 3, 2010
For the first time in 43,000 years, a woolly mammoth has breathed again on earth.
Well, not the mammoth itself but its hemoglobin, the stuff in red blood cells that takes on oxygen in the lungs and offloads it in the tissues. By reconstructing the mammoth’s hemoglobin, a team led by Kevin L. Campbell of the University of Manitoba in Canada has discovered how the once-tropical species adapted to living in arctic temperatures.
Dr. Campbell’s work raises a somewhat astonishing possibility: that much of the physiology of extinct animals may one day be recoverable from the DNA extracted from their remains.
“It is a very exciting result and opens a new chapter in paleontology, a subject usually constrained to examining old bones and teeth,” said Adrian Lister, an expert on mammoth evolution at the Natural History Museum in London.
Mammoths, despite their association with the frozen north, originated in the tropics when they split apart from elephants some seven million years ago. To adapt to the cold of northern latitudes, they developed smaller ears, a thick fur coat and glands in their skin to keep the fur well oiled.
So much is clear from their remains. But other kinds of adaptation, which have not survived, would also have been necessary. Most arctic animals arrange their blood vessels so that the arteries going down a leg can transfer heat to the veins coming up. The blood reaching the toes is thus quite cold, and the animal conserves lots of heat while it stands on frozen ground.
But this arrangement raises a problem for the hemoglobin, the protein of red blood cells that takes on oxygen in the lungs and delivers it in the tissues. The offloading process becomes much less efficient at low temperatures. So animals like the arctic fox, whose foot temperature is just a degree or so above freezing, have changes in their hemoglobin genes that enable the protein to release oxygen more easily at very low temperatures.
Dr. Campbell set out nine years ago to see if the same was true of mammoths. His first problem was to figure out which of several globin genes were active in the species. Globin genes make the four globin chains from which the hemoglobin molecule is assembled. Humans have at least four globin genes — alpha, beta, gamma and delta. Most hemoglobin molecules in human blood consist of two alpha chains and two beta chains, but in 10 percent of the blood, delta chains substitute for the betas. The gamma globin gene is active only in the fetus.
Dr. Campbell figured that the hemoglobin system of living elephants would offer the best guide to how mammoth globin genes operate. After a frustrating effort to get permits to take samples from wild elephants, he acquired blood from an Asian elephant called Caesar at the Bowmanville Zoo in Ontario.
It turned out that way back in the elephant lineage, the beta and delta globin genes had swapped DNA to create a hybrid beta-delta chain. Elephant hemoglobin molecules are composed of two chains from the alpha globin gene and two from the fused beta-delta gene, and it is reasonable to assume mammoths had the same system.
With this knowledge, Dr. Campbell and his colleagues could construct the tools to fish out the alpha and beta-delta globin genes from the ancient DNA of three permafrost-preserved Siberian mammoths that lived between 25,000 and 43,000 years ago. They found the alpha chain differed in one of its amino acid units from that of Asian elephants, and the beta-delta chain differed in three units from its counterpart, they report in Nature Genetics.
The team’s next step was to synthesize copies of the mammoth’s two globin genes. Instead of doing that from scratch, Dr. Campbell used a technique for altering DNA units one by one and simply converted the Asian elephant’s two globin genes at the four differing sites to the mammoth version. The mammoth genes were then inserted into bacteria, which synthesized the two mammoth globin chains, inserted the required iron atoms, and assembled the chains into working hemoglobin molecules. With the mammoth hemoglobin in hand, Dr. Campbell could at last address the question of whether its genetic changes had been shaped by natural selection to help mammoths survive in the cold.
“It’s the same as if I went back 43,000 years in a time machine and took blood from a mammoth,” he said.
The answer was yes: In a chemical environment like that in red blood cells, the reconstructed mammoth hemoglobin let go of its oxygen much more readily at cold temperatures than did that of Asian elephants.
The DNA changes in the mammoth hemoglobin genes differ from those in other arctic animals, an instance of convergent evolution or attaining the same end by a different genetic route.
One species that did not modify its hemoglobin genes to cope with arctic temperatures is that of humans. “With our ability to make mitts and hats, we’ve not needed these sorts of changes,” Dr. Campbell said.
He is now reconstructing important proteins of other extinct species such as the mastodon, the woolly rhinoceros and the Steller’s sea cow, a huge dugong that lived in the arctic.
Two years ago, scientists at Penn State University sequenced a large part of the mammoth’s genome from a clump of hair. They published the sequence along with the arresting suggestion that for just $10 million it might be possible to complete the sequence and use it to generate a living mammoth.
The suggestion was not as wild as it might seem, given that the idea came from George Church, a leading genome technologist at the Harvard Medical School. The mammoth’s genome differs at about 400,000 sites from that of the African elephant. Dr. Church has been developing a method for altering 50,000 sites at a time, though he is not at present applying it to mammoths. In converting four sites on the elephant genome to the mammoth version, Dr. Campbell has resurrected at least one tiny part of the mammoth.
Reconstructing the whole animal will take a little longer. “I’m 42 years old,” he said, “but I doubt I’ll ever see a living mammoth.”
Farmers Cope With Roundup-Resistant Weeds
By WILLIAM NEUMAN and ANDREW POLLACK, May 3, 2010
DYERSBURG, Tenn. — For 15 years, Eddie Anderson, a farmer, has been a strict adherent of no-till agriculture, an environmentally friendly technique that all but eliminates plowing to curb erosion and the harmful runoff of fertilizers and pesticides.
But not this year.
On a recent afternoon here, Mr. Anderson watched as tractors crisscrossed a rolling field — plowing and mixing herbicides into the soil to kill weeds where soybeans will soon be planted.
Just as the heavy use of antibiotics contributed to the rise of drug-resistant supergerms, American farmers’ near-ubiquitous use of the weedkiller Roundup has led to the rapid growth of tenacious new superweeds.
To fight them, Mr. Anderson and farmers throughout the East, Midwest and South are being forced to spray fields with more toxic herbicides, pull weeds by hand and return to more labor-intensive methods like regular plowing.
“We’re back to where we were 20 years ago,” said Mr. Anderson, who will plow about one-third of his 3,000 acres of soybean fields this spring, more than he has in years. “We’re trying to find out what works.”
Farm experts say that such efforts could lead to higher food prices, lower crop yields, rising farm costs and more pollution of land and water.
“It is the single largest threat to production agriculture that we have ever seen,” said Andrew Wargo III, the president of the Arkansas Association of Conservation Districts.
The first resistant species to pose a serious threat to agriculture was spotted in a Delaware soybean field in 2000. Since then, the problem has spread, with 10 resistant species in at least 22 states infesting millions of acres, predominantly soybeans, cotton and corn.
The superweeds could temper American agriculture’s enthusiasm for some genetically modified crops. Soybeans, corn and cotton that are engineered to survive spraying with Roundup have become standard in American fields. However, if Roundup doesn’t kill the weeds, farmers have little incentive to spend the extra money for the special seeds.
Roundup — originally made by Monsanto but now also sold by others under the generic name glyphosate — has been little short of a miracle chemical for farmers. It kills a broad spectrum of weeds, is easy and safe to work with, and breaks down quickly, reducing its environmental impact.
Sales took off in the late 1990s, after Monsanto created its brand of Roundup Ready crops that were genetically modified to tolerate the chemical, allowing farmers to spray their fields to kill the weeds while leaving the crop unharmed. Today, Roundup Ready crops account for about 90 percent of the soybeans and 70 percent of the corn and cotton grown in the United States.
But farmers sprayed so much Roundup that weeds quickly evolved to survive it. “What we’re talking about here is Darwinian evolution in fast-forward,” Mike Owen, a weed scientist at Iowa State University, said.
Now, Roundup-resistant weeds like horseweed and giant ragweed are forcing farmers to go back to more expensive techniques that they had long ago abandoned.
Mr. Anderson, the farmer, is wrestling with a particularly tenacious species of glyphosate-resistant pest called Palmer amaranth, or pigweed, whose resistant form began seriously infesting farms in western Tennessee only last year.
Pigweed can grow three inches a day and reach seven feet or more, choking out crops; it is so sturdy that it can damage harvesting equipment. In an attempt to kill the pest before it becomes that big, Mr. Anderson and his neighbors are plowing their fields and mixing herbicides into the soil.
That threatens to reverse one of the agricultural advances bolstered by the Roundup revolution: minimum-till farming. By combining Roundup and Roundup Ready crops, farmers did not have to plow under the weeds to control them. That reduced erosion, the runoff of chemicals into waterways and the use of fuel for tractors.
If frequent plowing becomes necessary again, “that is certainly a major concern for our environment,” Ken Smith, a weed scientist at the University of Arkansas, said. In addition, some critics of genetically engineered crops say that the use of extra herbicides, including some old ones that are less environmentally tolerable than Roundup, belies the claims made by the biotechnology industry that its crops would be better for the environment.
“The biotech industry is taking us into a more pesticide-dependent agriculture when they’ve always promised, and we need to be going in, the opposite direction,” said Bill Freese, a science policy analyst for the Center for Food Safety in Washington.
So far, weed scientists estimate that the total amount of United States farmland afflicted by Roundup-resistant weeds is relatively small — seven million to 10 million acres, according to Ian Heap, director of the International Survey of Herbicide Resistant Weeds, which is financed by the agricultural chemical industry. There are roughly 170 million acres planted with corn, soybeans and cotton, the crops most affected.
Roundup-resistant weeds are also found in several other countries, including Australia, China and Brazil, according to the survey.
Monsanto, which once argued that resistance would not become a major problem, now cautions against exaggerating its impact. “It’s a serious issue, but it’s manageable,” said Rick Cole, who manages weed resistance issues in the United States for the company.
Of course, Monsanto stands to lose a lot of business if farmers use less Roundup and Roundup Ready seeds.
“You’re having to add another product with the Roundup to kill your weeds,” said Steve Doster, a corn and soybean farmer in Barnum, Iowa. “So then why are we buying the Roundup Ready product?”
Monsanto argues that Roundup still controls hundreds of weeds. But the company is concerned enough about the problem that it is taking the extraordinary step of subsidizing cotton farmers’ purchases of competing herbicides to supplement Roundup.
Monsanto and other agricultural biotech companies are also developing genetically engineered crops resistant to other herbicides.
Bayer is already selling cotton and soybeans resistant to glufosinate, another weedkiller. Monsanto’s newest corn is tolerant of both glyphosate and glufosinate, and the company is developing crops resistant to dicamba, an older pesticide. Syngenta is developing soybeans tolerant of its Callisto product. And Dow Chemical is developing corn and soybeans resistant to 2,4-D, a component of Agent Orange, the defoliant used in the Vietnam War.
Still, scientists and farmers say that glyphosate is a once-in-a-century discovery, and steps need to be taken to preserve its effectiveness.
Glyphosate “is as important for reliable global food production as penicillin is for battling disease,” Stephen B. Powles, an Australian weed expert, wrote in a commentary in January in The Proceedings of the National Academy of Sciences.
The National Research Council, which advises the federal government on scientific matters, sounded its own warning last month, saying that the emergence of resistant weeds jeopardized the substantial benefits that genetically engineered crops were providing to farmers and the environment.
Weed scientists are urging farmers to alternate glyphosate with other herbicides. But the price of glyphosate has been falling as competition increases from generic versions, encouraging farmers to keep relying on it.
Something needs to be done, said Louie Perry Jr., a cotton grower whose great-great-grandfather started his farm in Moultrie, Ga., in 1830.
Georgia has been one of the states hit hardest by Roundup-resistant pigweed, and Mr. Perry said the pest could pose as big a threat to cotton farming in the South as the beetle that devastated the industry in the early 20th century.
“If we don’t whip this thing, it’s going to be like the boll weevil did to cotton,” said Mr. Perry, who is also chairman of the Georgia Cotton Commission. “It will take it away.”
William Neuman reported from Dyersburg, Tenn., and Andrew Pollack from Los Angeles.
When the Ties That Bind Unravel
By TARA PARKER-POPE, The New York Times, May 3, 2010
Therapists for years have listened to patients blame parents for their problems. Now there is growing interest in the other side of the story: What about the suffering of parents who are estranged from their adult children?
While there are no official tallies of parents whose adult children have cut them off, there is no shortage of headlines. The Olympic gold medal skier Lindsey Vonn reportedly hasn’t spoken to her father in at least four years. The actor Jon Voight and his daughter, Angelina Jolie, were photographed together in February for the first time since they were estranged in 2002.
A number of Web sites and online chat rooms are devoted to the issue, with heartbreaking tales of children who refuse their parents’ phone calls and e-mail and won’t let them see grandchildren. Some parents seek grief counseling, while others fall into depression and even contemplate suicide.
Joshua Coleman, a San Francisco psychologist who is an expert on parental estrangement, says it appears to be growing more and more common, even in families who haven’t experienced obvious cruelty or traumas like abuse and addiction. Instead, parents often report that a once-close relationship has deteriorated after a conflict over money, a boyfriend or built-up resentments about a parent’s divorce or remarriage.
“We live in a culture that assumes if there is an estrangement, the parents must have done something really terrible,” said Dr. Coleman, whose book “When Parents Hurt” (William Morrow, 2007) focuses on estrangement. “But this is not a story of adult children cutting off parents who made egregious mistakes. It’s about parents who were good parents, who made mistakes that were certainly within normal limits.”
Dr. Coleman himself experienced several years of estrangement with his adult daughter, with whom he has reconciled. Mending the relationship took time and a persistent effort by Dr. Coleman to stay in contact. It also meant listening to his daughter’s complaints and accepting responsibility for his mistakes. “I tried to really get what her feelings were and tried to make amends and repair,” he said. “Over the course of several years, it came back slowly.”
Not every parent is so successful. Debby Kintner of Somerville, Tenn., sought grief counseling after her adult daughter, and only child, ended their relationship. “It hit me like a freight train,” she said. “I sit down and comb through my memories and try to figure out which day was it that it went wrong. I don’t know.”
Ms. Kintner talks of life as a single parent, raising an honor student who insisted her mother accompany her on a class trip to London, a college student who made frequent calls and visits home. Things changed after her daughter began an on-again, off-again relationship with a boyfriend and moved back home after becoming pregnant. Arguments about her daughter’s decision to move in with the man and Ms. Kintner’s refusal to give her daughter a car eventually led to estrangement. She now has no contact with her daughter or three grandchildren.
“I knew parents and children had fights, but there was enough love to come back together,” Ms. Kintner said. “This is your mother who gave you a nice life and loved you.’ “
Judith, a mother in Augusta, Ga., who asked that her last name not be used, tells of a loving, creative daughter who experienced a turbulent adolescence. At college graduation, the parents were shocked when their daughter unleashed an angry tirade about her childhood. Later, the daughter asked for financial help paying for an Ivy League graduate school. The parents agreed, but a visit to see her on the East Coast was marred by another round of harsh words and accusations. They withdrew their financial support and returned home.
“I’ve done a lot of crying,” said Judith, who has sought therapy to cope. “I’m very depressed. All the holidays are sad, and we don’t have any closure on this. She was so wanted. She was so loved. She still is loved. We want her in our life.”
Dr. Coleman says he believes parental estrangement is a “silent epidemic,” because many parents are ashamed to admit they’ve lost contact with their children.
Often, he said, parents in these situations give up too soon. He advises them to continue weekly letters, e-mail messages or phone calls even when they are rejected, and to be generous in taking responsibility for their mistakes — even if they did not seem like mistakes at the time.
After all, he went on, parents and children have very different perspectives. “It’s possible for a parent to feel like they were doing something out of love,” he said, “but it didn’t feel like love to that child.”
Friends, other family members and therapists can often help a parent cope with the loss of an estranged child. So can patience: reconciliation usually takes many conversations, not just one.
“When I was going through this, it was a gray cloud, a nightmare,” Dr. Coleman said. “Don’t just assume if your child is rejecting you that that’s the end of the conversation. Parents have to be on a campaign to let the child know that they’re in it for the long haul.”
By DONALD G. McNEIL Jr., The New York Times, May 3, 2010
Giving women vitamin A capsules did not save their lives or the lives of their new babies, according to a surprising new study from Ghana reported this week by the medical journal Lancet.
The results contradicted an earlier study in Nepal that showed a huge drop in deaths among child-bearing women taking vitamin A, and disappointed experts who hoped pills could be a cheap, easy lifesaver. Scientists did establish in the 1980s that giving vitamin A to malnourished children prevented stunting and deaths from measles and diarrhea.
The 1999 study in Nepal suggested the vitamin also saved young mothers, although that result was regarded somewhat skeptically because so many of the women had died of unrelated causes, including burns, drowning, snakebite and hanging.
Writing in a Lancet commentary, Anthony Costello and David Osrin of the global health institute of University College London noted that the new study recruited an “astonishing” number of women — nearly 208,000 in more than 1,000 villages or family compounds.
Half got a weekly low dose of vitamin A, and half got a placebo. Few in either group died, but the vitamin also did not reduce hospitalization for childbirth complications. Nor did it reduce stillbirths or deaths of newborns. Recent trials in Bangladesh and Indonesia had similar results.
Finding ways to get more food to young women might be more effective than getting them vitamin pills, the commentary’s authors said.
Mammoth Hemoglobin Offers More Clues to Its Arctic Evolution
By NICHOLAS WADE, The New York Times, May 3, 2010
For the first time in 43,000 years, a woolly mammoth has breathed again on earth.
Well, not the mammoth itself but its hemoglobin, the stuff in red blood cells that takes on oxygen in the lungs and offloads it in the tissues. By reconstructing the mammoth’s hemoglobin, a team led by Kevin L. Campbell of the University of Manitoba in Canada has discovered how the once-tropical species adapted to living in arctic temperatures.
Dr. Campbell’s work raises a somewhat astonishing possibility: that much of the physiology of extinct animals may one day be recoverable from the DNA extracted from their remains.
“It is a very exciting result and opens a new chapter in paleontology, a subject usually constrained to examining old bones and teeth,” said Adrian Lister, an expert on mammoth evolution at the Natural History Museum in London.
Mammoths, despite their association with the frozen north, originated in the tropics when they split apart from elephants some seven million years ago. To adapt to the cold of northern latitudes, they developed smaller ears, a thick fur coat and glands in their skin to keep the fur well oiled.
So much is clear from their remains. But other kinds of adaptation, which have not survived, would also have been necessary. Most arctic animals arrange their blood vessels so that the arteries going down a leg can transfer heat to the veins coming up. The blood reaching the toes is thus quite cold, and the animal conserves lots of heat while it stands on frozen ground.
But this arrangement raises a problem for the hemoglobin, the protein of red blood cells that takes on oxygen in the lungs and delivers it in the tissues. The offloading process becomes much less efficient at low temperatures. So animals like the arctic fox, whose foot temperature is just a degree or so above freezing, have changes in their hemoglobin genes that enable the protein to release oxygen more easily at very low temperatures.
Dr. Campbell set out nine years ago to see if the same was true of mammoths. His first problem was to figure out which of several globin genes were active in the species. Globin genes make the four globin chains from which the hemoglobin molecule is assembled. Humans have at least four globin genes — alpha, beta, gamma and delta. Most hemoglobin molecules in human blood consist of two alpha chains and two beta chains, but in 10 percent of the blood, delta chains substitute for the betas. The gamma globin gene is active only in the fetus.
Dr. Campbell figured that the hemoglobin system of living elephants would offer the best guide to how mammoth globin genes operate. After a frustrating effort to get permits to take samples from wild elephants, he acquired blood from an Asian elephant called Caesar at the Bowmanville Zoo in Ontario.
It turned out that way back in the elephant lineage, the beta and delta globin genes had swapped DNA to create a hybrid beta-delta chain. Elephant hemoglobin molecules are composed of two chains from the alpha globin gene and two from the fused beta-delta gene, and it is reasonable to assume mammoths had the same system.
With this knowledge, Dr. Campbell and his colleagues could construct the tools to fish out the alpha and beta-delta globin genes from the ancient DNA of three permafrost-preserved Siberian mammoths that lived between 25,000 and 43,000 years ago. They found the alpha chain differed in one of its amino acid units from that of Asian elephants, and the beta-delta chain differed in three units from its counterpart, they report in Nature Genetics.
The team’s next step was to synthesize copies of the mammoth’s two globin genes. Instead of doing that from scratch, Dr. Campbell used a technique for altering DNA units one by one and simply converted the Asian elephant’s two globin genes at the four differing sites to the mammoth version. The mammoth genes were then inserted into bacteria, which synthesized the two mammoth globin chains, inserted the required iron atoms, and assembled the chains into working hemoglobin molecules. With the mammoth hemoglobin in hand, Dr. Campbell could at last address the question of whether its genetic changes had been shaped by natural selection to help mammoths survive in the cold.
“It’s the same as if I went back 43,000 years in a time machine and took blood from a mammoth,” he said.
The answer was yes: In a chemical environment like that in red blood cells, the reconstructed mammoth hemoglobin let go of its oxygen much more readily at cold temperatures than did that of Asian elephants.
The DNA changes in the mammoth hemoglobin genes differ from those in other arctic animals, an instance of convergent evolution or attaining the same end by a different genetic route.
One species that did not modify its hemoglobin genes to cope with arctic temperatures is that of humans. “With our ability to make mitts and hats, we’ve not needed these sorts of changes,” Dr. Campbell said.
He is now reconstructing important proteins of other extinct species such as the mastodon, the woolly rhinoceros and the Steller’s sea cow, a huge dugong that lived in the arctic.
Two years ago, scientists at Penn State University sequenced a large part of the mammoth’s genome from a clump of hair. They published the sequence along with the arresting suggestion that for just $10 million it might be possible to complete the sequence and use it to generate a living mammoth.
The suggestion was not as wild as it might seem, given that the idea came from George Church, a leading genome technologist at the Harvard Medical School. The mammoth’s genome differs at about 400,000 sites from that of the African elephant. Dr. Church has been developing a method for altering 50,000 sites at a time, though he is not at present applying it to mammoths. In converting four sites on the elephant genome to the mammoth version, Dr. Campbell has resurrected at least one tiny part of the mammoth.
Reconstructing the whole animal will take a little longer. “I’m 42 years old,” he said, “but I doubt I’ll ever see a living mammoth.”
Farmers Cope With Roundup-Resistant Weeds
By WILLIAM NEUMAN and ANDREW POLLACK, May 3, 2010
DYERSBURG, Tenn. — For 15 years, Eddie Anderson, a farmer, has been a strict adherent of no-till agriculture, an environmentally friendly technique that all but eliminates plowing to curb erosion and the harmful runoff of fertilizers and pesticides.
But not this year.
On a recent afternoon here, Mr. Anderson watched as tractors crisscrossed a rolling field — plowing and mixing herbicides into the soil to kill weeds where soybeans will soon be planted.
Just as the heavy use of antibiotics contributed to the rise of drug-resistant supergerms, American farmers’ near-ubiquitous use of the weedkiller Roundup has led to the rapid growth of tenacious new superweeds.
To fight them, Mr. Anderson and farmers throughout the East, Midwest and South are being forced to spray fields with more toxic herbicides, pull weeds by hand and return to more labor-intensive methods like regular plowing.
“We’re back to where we were 20 years ago,” said Mr. Anderson, who will plow about one-third of his 3,000 acres of soybean fields this spring, more than he has in years. “We’re trying to find out what works.”
Farm experts say that such efforts could lead to higher food prices, lower crop yields, rising farm costs and more pollution of land and water.
“It is the single largest threat to production agriculture that we have ever seen,” said Andrew Wargo III, the president of the Arkansas Association of Conservation Districts.
The first resistant species to pose a serious threat to agriculture was spotted in a Delaware soybean field in 2000. Since then, the problem has spread, with 10 resistant species in at least 22 states infesting millions of acres, predominantly soybeans, cotton and corn.
The superweeds could temper American agriculture’s enthusiasm for some genetically modified crops. Soybeans, corn and cotton that are engineered to survive spraying with Roundup have become standard in American fields. However, if Roundup doesn’t kill the weeds, farmers have little incentive to spend the extra money for the special seeds.
Roundup — originally made by Monsanto but now also sold by others under the generic name glyphosate — has been little short of a miracle chemical for farmers. It kills a broad spectrum of weeds, is easy and safe to work with, and breaks down quickly, reducing its environmental impact.
Sales took off in the late 1990s, after Monsanto created its brand of Roundup Ready crops that were genetically modified to tolerate the chemical, allowing farmers to spray their fields to kill the weeds while leaving the crop unharmed. Today, Roundup Ready crops account for about 90 percent of the soybeans and 70 percent of the corn and cotton grown in the United States.
But farmers sprayed so much Roundup that weeds quickly evolved to survive it. “What we’re talking about here is Darwinian evolution in fast-forward,” Mike Owen, a weed scientist at Iowa State University, said.
Now, Roundup-resistant weeds like horseweed and giant ragweed are forcing farmers to go back to more expensive techniques that they had long ago abandoned.
Mr. Anderson, the farmer, is wrestling with a particularly tenacious species of glyphosate-resistant pest called Palmer amaranth, or pigweed, whose resistant form began seriously infesting farms in western Tennessee only last year.
Pigweed can grow three inches a day and reach seven feet or more, choking out crops; it is so sturdy that it can damage harvesting equipment. In an attempt to kill the pest before it becomes that big, Mr. Anderson and his neighbors are plowing their fields and mixing herbicides into the soil.
That threatens to reverse one of the agricultural advances bolstered by the Roundup revolution: minimum-till farming. By combining Roundup and Roundup Ready crops, farmers did not have to plow under the weeds to control them. That reduced erosion, the runoff of chemicals into waterways and the use of fuel for tractors.
If frequent plowing becomes necessary again, “that is certainly a major concern for our environment,” Ken Smith, a weed scientist at the University of Arkansas, said. In addition, some critics of genetically engineered crops say that the use of extra herbicides, including some old ones that are less environmentally tolerable than Roundup, belies the claims made by the biotechnology industry that its crops would be better for the environment.
“The biotech industry is taking us into a more pesticide-dependent agriculture when they’ve always promised, and we need to be going in, the opposite direction,” said Bill Freese, a science policy analyst for the Center for Food Safety in Washington.
So far, weed scientists estimate that the total amount of United States farmland afflicted by Roundup-resistant weeds is relatively small — seven million to 10 million acres, according to Ian Heap, director of the International Survey of Herbicide Resistant Weeds, which is financed by the agricultural chemical industry. There are roughly 170 million acres planted with corn, soybeans and cotton, the crops most affected.
Roundup-resistant weeds are also found in several other countries, including Australia, China and Brazil, according to the survey.
Monsanto, which once argued that resistance would not become a major problem, now cautions against exaggerating its impact. “It’s a serious issue, but it’s manageable,” said Rick Cole, who manages weed resistance issues in the United States for the company.
Of course, Monsanto stands to lose a lot of business if farmers use less Roundup and Roundup Ready seeds.
“You’re having to add another product with the Roundup to kill your weeds,” said Steve Doster, a corn and soybean farmer in Barnum, Iowa. “So then why are we buying the Roundup Ready product?”
Monsanto argues that Roundup still controls hundreds of weeds. But the company is concerned enough about the problem that it is taking the extraordinary step of subsidizing cotton farmers’ purchases of competing herbicides to supplement Roundup.
Monsanto and other agricultural biotech companies are also developing genetically engineered crops resistant to other herbicides.
Bayer is already selling cotton and soybeans resistant to glufosinate, another weedkiller. Monsanto’s newest corn is tolerant of both glyphosate and glufosinate, and the company is developing crops resistant to dicamba, an older pesticide. Syngenta is developing soybeans tolerant of its Callisto product. And Dow Chemical is developing corn and soybeans resistant to 2,4-D, a component of Agent Orange, the defoliant used in the Vietnam War.
Still, scientists and farmers say that glyphosate is a once-in-a-century discovery, and steps need to be taken to preserve its effectiveness.
Glyphosate “is as important for reliable global food production as penicillin is for battling disease,” Stephen B. Powles, an Australian weed expert, wrote in a commentary in January in The Proceedings of the National Academy of Sciences.
The National Research Council, which advises the federal government on scientific matters, sounded its own warning last month, saying that the emergence of resistant weeds jeopardized the substantial benefits that genetically engineered crops were providing to farmers and the environment.
Weed scientists are urging farmers to alternate glyphosate with other herbicides. But the price of glyphosate has been falling as competition increases from generic versions, encouraging farmers to keep relying on it.
Something needs to be done, said Louie Perry Jr., a cotton grower whose great-great-grandfather started his farm in Moultrie, Ga., in 1830.
Georgia has been one of the states hit hardest by Roundup-resistant pigweed, and Mr. Perry said the pest could pose as big a threat to cotton farming in the South as the beetle that devastated the industry in the early 20th century.
“If we don’t whip this thing, it’s going to be like the boll weevil did to cotton,” said Mr. Perry, who is also chairman of the Georgia Cotton Commission. “It will take it away.”
William Neuman reported from Dyersburg, Tenn., and Andrew Pollack from Los Angeles.
When the Ties That Bind Unravel
By TARA PARKER-POPE, The New York Times, May 3, 2010
Therapists for years have listened to patients blame parents for their problems. Now there is growing interest in the other side of the story: What about the suffering of parents who are estranged from their adult children?
While there are no official tallies of parents whose adult children have cut them off, there is no shortage of headlines. The Olympic gold medal skier Lindsey Vonn reportedly hasn’t spoken to her father in at least four years. The actor Jon Voight and his daughter, Angelina Jolie, were photographed together in February for the first time since they were estranged in 2002.
A number of Web sites and online chat rooms are devoted to the issue, with heartbreaking tales of children who refuse their parents’ phone calls and e-mail and won’t let them see grandchildren. Some parents seek grief counseling, while others fall into depression and even contemplate suicide.
Joshua Coleman, a San Francisco psychologist who is an expert on parental estrangement, says it appears to be growing more and more common, even in families who haven’t experienced obvious cruelty or traumas like abuse and addiction. Instead, parents often report that a once-close relationship has deteriorated after a conflict over money, a boyfriend or built-up resentments about a parent’s divorce or remarriage.
“We live in a culture that assumes if there is an estrangement, the parents must have done something really terrible,” said Dr. Coleman, whose book “When Parents Hurt” (William Morrow, 2007) focuses on estrangement. “But this is not a story of adult children cutting off parents who made egregious mistakes. It’s about parents who were good parents, who made mistakes that were certainly within normal limits.”
Dr. Coleman himself experienced several years of estrangement with his adult daughter, with whom he has reconciled. Mending the relationship took time and a persistent effort by Dr. Coleman to stay in contact. It also meant listening to his daughter’s complaints and accepting responsibility for his mistakes. “I tried to really get what her feelings were and tried to make amends and repair,” he said. “Over the course of several years, it came back slowly.”
Not every parent is so successful. Debby Kintner of Somerville, Tenn., sought grief counseling after her adult daughter, and only child, ended their relationship. “It hit me like a freight train,” she said. “I sit down and comb through my memories and try to figure out which day was it that it went wrong. I don’t know.”
Ms. Kintner talks of life as a single parent, raising an honor student who insisted her mother accompany her on a class trip to London, a college student who made frequent calls and visits home. Things changed after her daughter began an on-again, off-again relationship with a boyfriend and moved back home after becoming pregnant. Arguments about her daughter’s decision to move in with the man and Ms. Kintner’s refusal to give her daughter a car eventually led to estrangement. She now has no contact with her daughter or three grandchildren.
“I knew parents and children had fights, but there was enough love to come back together,” Ms. Kintner said. “This is your mother who gave you a nice life and loved you.’ “
Judith, a mother in Augusta, Ga., who asked that her last name not be used, tells of a loving, creative daughter who experienced a turbulent adolescence. At college graduation, the parents were shocked when their daughter unleashed an angry tirade about her childhood. Later, the daughter asked for financial help paying for an Ivy League graduate school. The parents agreed, but a visit to see her on the East Coast was marred by another round of harsh words and accusations. They withdrew their financial support and returned home.
“I’ve done a lot of crying,” said Judith, who has sought therapy to cope. “I’m very depressed. All the holidays are sad, and we don’t have any closure on this. She was so wanted. She was so loved. She still is loved. We want her in our life.”
Dr. Coleman says he believes parental estrangement is a “silent epidemic,” because many parents are ashamed to admit they’ve lost contact with their children.
Often, he said, parents in these situations give up too soon. He advises them to continue weekly letters, e-mail messages or phone calls even when they are rejected, and to be generous in taking responsibility for their mistakes — even if they did not seem like mistakes at the time.
After all, he went on, parents and children have very different perspectives. “It’s possible for a parent to feel like they were doing something out of love,” he said, “but it didn’t feel like love to that child.”
Friends, other family members and therapists can often help a parent cope with the loss of an estranged child. So can patience: reconciliation usually takes many conversations, not just one.
“When I was going through this, it was a gray cloud, a nightmare,” Dr. Coleman said. “Don’t just assume if your child is rejecting you that that’s the end of the conversation. Parents have to be on a campaign to let the child know that they’re in it for the long haul.”
