Glyphosate (gly-foh-sate) has become the most heavily used herbicide in the U.S. … and it's the active ingredient in Monsanto's Roundup product.
Once welcomed as a less-toxic, more rapidly bio-degraded alternative to older herbicides like atrazine, it's begun to show its own dark side.
The biotech firm's Roundup Ready corn and soy are bio-engineered to resist glyphosate, so farmers can apply it without (theoretically) harming their harvest.
The Roundup Ready system necessitates use of Monsanto's glyphosate-based herbicide … and with almost one-quarter of a billion acres of Roundup Ready crops planted, that's a profitable requirement.
According to David Ehrenfield, Professor of Biology at Rutgers University, "With very few exceptions, the whole point of genetic engineering is to increase sales of chemicals and bio-engineered products to dependent farmers.” (Waltz E 2009)
And he makes a key point: "In the United States, the widespread adoption of Roundup Ready crops combined with the emergence of glyphosate-resistant weeds has driven a more than 15-fold increase in the use of glyphosate on major field crops from 1994 to 2005.” (CFS 2008)
Already, greatly increased use of glyphosate over the past decade-plus has increased the proportion of weeds resistant to it.
Now, concerns about glyphosate have been heightened considerably.
Top scientist links Roundup to mystery pathogen and soil damage
Don Huber, Ph.D., is an eminent plant pathologist and a retired Army colonel who's advised the U.S. Government on biological threats to the food supply for more than 30 years.
Huber raised a red flag about a new risk from glyphosate in the form of a now-public letter to U.S. Secretary of Agriculture Tom Vilsack.
In that letter, Dr. Huber requested a delay in approval of Roundup Ready alfalfa, because of "… the discovery of an electron microscopic [sized] pathogen that appears to significantly impact the health of plants, animals and probably humans.”
Huber had been reluctant to go public, out of concern for scientific protocol and credibility, given the preliminary nature of the evidence.
There's overwhelming evidence that the virus-sized pathogen exists but it has not been identified.
Rather than being a new microbe, wide use of glyphosate seems to have created soil conditions that allow it to proliferate profusely.
Alarmingly, the mystery pathogen has been persuasively linked to increased crop disease and to sharply reduced fertility in livestock fed crops carrying large amounts of it.
For more than 20 years, Huber had been actively researching glyphosate's role in the soil ecosystem. His and other published research demonstrated that glyphosate ties up essential micronutrients, thereby interfering with the plant's immune system and encouraging disease.
Huber also noticed an association between glyphosate and bacterial diseases in citrus and soybeans.
Veterinary researchers have reported high levels of the mystery pathogen being found in corn silage and corn infected with Goss's wilt.
And as Huber, said, "We found the pathogen was prevalent when glyphosate was involved, even (in wheat) the year before. We started looking and found it was also highly prevalent in soybeans with SDS [sudden death syndrome].”
USDA brush-off leads to reluctant public warning
After Secretary Vilsack ignored his warning and approved Roundup Ready alfalfa, Dr. Huber felt so strongly about the serious nature of the threat that he overcame his hesitation and has been trying to get the word out.
Huber's fears began with research published by Robert Kremer, Ph.D., of the University of Missouri, and his colleagues in Brazil and at the USDA's Agricultural Research Service (Means NE et al. 2007; Zobiole LH et al. 2010 and 2011).
Their research indicates that key nutrients are withheld from soy and other legumes when glyphosate reaches the soil around their roots.
Since 1997, Kremer has been studying the impact of glyphosate-tolerant soybean varieties and corn hybrids, and has found that glyphosate consistently affects soil's biology and ecology.
Dr. Kremer has detected shifts in the composition of root microbe colonies … including changes in manganese reducing and oxidizing bacteria, which may affect availability of manganese to the plant and reduce desirable "nodulation” on soybean and other legume roots.
Root nodules occur on the roots of plants (primarily beans and other legumes) that associate with symbiotic nitrogen-fixing bacteria.
Within legume nodules, bacteria convert nitrogen from the atmosphere into ammonia, which is then assimilated into amino acids (the building blocks of proteins), nucleotides (the building blocks of DNA and RNA as well as the essential energy storage/transfer molecule ATP), and other key cell constituents such as vitamins, flavones, and hormones.
According to Kremer, "We consistently saw lots of fusarium [fungi] colonizing the roots of transgenic [genetically modified] plants] relative to conventional varieties with lower levels of fusarium.” (Ruen J 2011)
Glyphosate appears to tie up minerals in the plant, hurt nitrogen-fixing bacteria in the root nodules, and increase plant disease overall.
(Glyphosate's ability to promote microbial diseases is increasingly recognized as its main means of killing weeds and other plants.)
The combination of these effects concerns some agronomists, who fear crop failures from a "perfect storm” of weather stress and glyphosate-induced nutrient-deficiencies and fungal infections.
As he told Ag Professional magazine last month, plant pathologist Bob Streit, M.S., of Central Iowa Agronomics believes the concerns are serious:
"The scientists working on the pathogen are doing the work needed. They want all the data assembled correctly so it meets scientific scrutiny when it is published. Until then, they have to be protected so their work doesn't get shut down.” (Ruen J 2011)
You can say that again … big agribusiness and biotech have friends in high places, and provide much of the funding for universities' agricultural research.
Center for Food Safety (CFS). Genetically Modified (GM) Crops and Pesticide Use. January 2008. Accessed at http://www.centerforfoodsafety.org/pubs/GM%20Crops% 20and%20Herbicide%20Use%20-%20Jan%2008%20update%20_2_.pdf
Means NE, Kremer RJ, Ramsier C. Effects of glyphosate and foliar amendments on activity of microorganisms in the soybean rhizosphere. J Environ Sci Health B. 2007 Feb;42(2):125-32.
Ruen J. Glyphosate controversy requires research to resolve.Ag Professional Magazine. April 15, 2011. Accessed at http://www.agprofessional.com/agprofessional-magazine/ glyphosate_controversy_requires_research_to_resolve_121190348.html
Waltz E. Under Wraps. Nature Biotechnology, volume 27 number 10, October 2009.
Zobiole LH, Kremer RJ, Oliveira RS Jr, Constantin J. Glyphosate affects micro-organisms in rhizospheres of glyphosate-resistant soybeans. J Appl Microbiol. 2011 Jan;110(1):118-27. doi: 10.1111/j.1365-2672.2010.04864.x. Epub 2010 Sep 29.
Zobiole LH, Oliveira RS, Visentainer JV, Kremer RJ, Bellaloui N, Yamada T. Glyphosate affects seed composition in glyphosate-resistant soybean. J Agric Food Chem. 2010 Apr 14;58(7):4517-22.