ROUNDUP.Top of resistant weeds pose a threat to the environment

By David Mercer, associated Press, CHAMPAIGN, fig — when the weed killer ROUNDUP.Mount was introduced in the 1970s, has proved it can kill almost any plant but are still safer than many other herbicides, and enabled farmers to give up major chemicals and reduction of tilling that may contribute to erosion.But 24 years later, sturdy several species of weeds resistant to ROUNDUP.Góra evolved, forcing farmers to return to some of the less secure practice abandoned decades earlier.The situation is worst in the South, where some farmers now walk the fields with hoes, killing weeds in their Great grandfathers were happy to leave behind. And the problem is quickly spreading belt corn and beyond, with the ROUND.Mount now proving unreliable in killing at least 10 species of weeds in at least 22 States. Some species, like the Palmer Amaranth in Arkansas and water hemp and marestail in Illinois, quickly grow and large, producing tens of thousands of seeds. "It's getting too big case," says Mike Plummer, 61-year-old farmer and agronomist at the University of Illinois, which soybeans and cotton near Southern Illinois Creal Springs Community. "If you got it, this is a real big deal."When Monsanto introduced Roundup in 1976, "since sliced bread, it was like the best thing," said Garry Niemeyer, who grows corn and soybeans near Auburn in Central Illinois. The weed killer, known generically as glyphosate, is absorbed by the plants leaves and kills them by blocking the production of the protein they need to grow. The US Environmental Protection Agency considers that have low toxicity for humans and animals, and plants is sprayed on, there is less danger to the environment because it rapidly binds to soil and becomes inactive.The introduction of Monsanto seeds designed to survive the ROUND.Mountain made things even better for farmers, because it can spray on emerging weeds growing crops erase beside them. Seeds containing Monsanto's Roundup Ready features are now used to grow approximately 90% of the soybeans nation and 70% of its maize and cotton.With increased dependence on Roundup herbicide to corn fell from 2,76 pounds per Acre in 1994 to 2.06 in 2005, the most-recent year for which the U.S. Department of Agriculture has no data. Distributed over 81.8 million acres planted in 2005 and annually is a decrease of more than 57 million pounds of herbicides.Farmers also found they could reduce, or in some cases, eliminating tilling, reducing erosion and fuel.But with all herbicides, the more it is used, the more likely that it will run individual plants within a species, which have only a few genetic varieties survive which kills most of their relatives. With each generation of the survivors they represent a larger percentage of species St. Louis-based Monsanto maintains resistance is often overstated, noting that most weeds show signs of immunity. "We believe that glyphosate will remain an important tool in the Arsenal of farmers, "said Monsanto Spokesman John Combest. Nevertheless, the company began paying cotton farmers $ 12 an acre to cover the costs of the other herbicides for Use next to Roundup, to increase its effectiveness.Trend confirmed by certain groups of food safety in the belief that biotechnology will not restrict the use of chemicals in the long term "that is were converted," says Bill Freese, chemist with a Washington, D.C.: Center for food safety, which promotes organic farming. "They intend to significantly increase the use of these chemicals, and that is bad."The first weeds in the United States, which survived the ROUND.Góra, it was found that about 10 years ago in Delaware. Agricultural experts said the use of other chemicals is already Creeping up. Monsanto and other companies develop new seeds intended to resist older herbicides such as dicamba and 2,4-D, killer weed developed during World War II and a component of Agent Orange, which was used to destroy the jungle foliage during the war in Vietnam and is blamed for health problems among veterans.Penn State University Weed scientist David Mortensen, estimated that in three or four years, farmers use dicamba and 2,4-D will be increased by 55.1 million pounds in the year due to resistance to ROUNDUP.Góra. That would both far list of herbicides used intensively by the farmers.Dicamba and 2,4-D easily drift outside the areas where you are sprayed, making them a threat to neighbouring crops and wild plants, "said Mortensen. Which, in turn, could also endanger wildlife. "We found that the plants (wild), which grows on the edge of the field actually supports the beneficial insects such as bees, "he said.Australian scientist Stephen Powles was sort of weed Evangelist recording Roundup, calling this tool in near miraculous agriculture.Australia has been involved in the ROUNDUP.Top of resistant weeds from the mid-1990s, but changes in farming practices that have helped to conduct effective, he said. That is enabled using a wider array of herbicides to kill off weeds ROUND.Góra, resistant and using other methods of weed control.These alternative methods, such as planting cover crops, the so-called "such as rye to deter weeds during the winter and in other cases, when the fields are planted with corn, soybeans and cotton, are key," said Freese, chemist, Center for food safety.Otherwise, he said, "that we are talking here of pesticide treadmill. This is only coming back to kick us in the butt now with resistant weeds. "Copyright 2010 Associated Press. 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