BOULDER, CO (January 18, 2010) – A new study entitled “Gene amplification confers glyphosate resistance in Amaranthus palmeri” from a research team including Monsanto scientists Dafu Wang and Douglas Sammons echoes conclusions from The Organic Center (TOC) report “Impacts of Genetically Engineered Crops on Pesticide Use in the United States: The First Thirteen Years”. Published in Proceedings of National Academy of Sciences (PNAS) in December 2009, the Monsanto-funded research states that “evolution of resistance to the widely used, nonselective herbicide glyphosate in weedy species endangers the continued success of transgenic glyphosate-resistant crops and the sustainability of glyphosate as the world’s most important herbicide.”

In other words, the plants are learning to resist.

Similarly, TOC’s report demonstrates compelling evidence linking the increase in herbicide use on GE, herbicide-tolerant (HT) crops to the emergence and spread of glyphosate-resistant weeds including Amaranthus palmeri. Based upon data from the U.S. Department of Agriculture (USDA), report author Dr. Charles Benbrook shows that glyphosate-based, HT corn, soybeans and cotton have increased herbicide use by 383 million pounds in the U.S. from 1996 to 2008 with 46 percent of the total increase occurring in 2007 and 2008.

“This unequivocal admission of serious problems with glyphosate-based HT cropping systems will hopefully accelerate major changes in where and how HT technology is deployed,” said Dr. Charles Benbrook, chief scientist of The Organic Center. “Such changes are needed to slow the increase in cash expenditures by farmers on herbicides and public health and environmental problems triggered by increased use of herbicides on GE crops.”

In statements to the media in reaction to TOC’s “Impacts of Genetically Engineered Crops on Pesticide Use in the U.S.” report, Monsanto representatives have disputed the severity of the resistance-driven crisis facing glyphosate-based HT crops. In an article appearing in Peoria’s Journal Star titled “Attack of the Superweeds,” Monsanto spokesperson Darren Wallis was quoted as saying, “We’ve identified only a small number of Roundup Ready resistant weeds – 12. Roundup has been around for many decades and still controls over 300 weeds.”

To view a full version of The Organic Center’s “Impacts of Genetically Engineered Crops on Pesticide Use in the United States: The First Thirteen Years”, visit

To view a full version of “Gene amplification confers glyphosate resistance in Amaranthus palmeri”, visit

About The Organic Center
The Organic Center’s unique mission is to advance scientific research on the health and environmental benefits of organic foods, and to communicate those benefits to the public. As an independent nonprofit 501©(3) research and education organization, we envision improved health for the earth and its inhabitants through conversion of agriculture to organic methods. All of The Organic Center’s research reports, publications, consumer guides and videos are available free of charge on our website,