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Herbicide resistance one of the challenges facing Monsanto
(Friday, June 18, 2004 -- CropChoice guest commentary) -- Monsanto is a leading global provider of agricultural products and systems sold to farming concerns. Their leading products are the Roundup herbicide, DEKALB and Agrow seed products, and biotechnology traits. Products have also included Agent Orange (1), PCBs, DDT and Bovine Growth Hormone. In the Washington Post article (Jan 1, 2002) "Monsanto Hid Decades Of Pollution PCBs Drenched Ala. Town, But No One Was Ever Told" a grim story of Monsanto's treacherous behaviour in Anniston Alabama was revealed. It is summed up in this chilling paragraph: "They also know that for nearly 40 years, while producing the now-banned industrial coolants known as PCBs at a local factory, Monsanto Co. routinely discharged toxic waste into a west Anniston creek and dumped millions of pounds of PCBs into oozing open-pit landfills. And thousands of pages of Monsanto documents -- many emblazoned with warnings such as "CONFIDENTIAL: Read and Destroy" -- show that for decades, the corporate giant concealed what it did and what it knew." [1] Monsanto's "Roundup Ready" products are manufactured to be "herbicide resistant" allowing farmers to drench their crops with many times the normal amount of herbicide so as to be able to kill nearby weeds without killing the crops (2). "RR soybeans are heavily herbicide dependent". [2] [3] [4] Exposure to glyphosate (the active ingredient in Roundup) increases the risk of non-Hodgkin lymphoma. [5]. See also [6]. Among the issues with GMOs, the manufacture of herbicide resistant biotech crops, particularly Monsanto's RR crops, has resulted in the creation of hard-to-kill "superweeds". [7][8][9]. Precisely because these crops were specifically designed to command much more herbicide use (primarily, some say, to increase profits for Monsanto), this overuse itself (similar to the escalating quandary of antibiotic overuse in humans) is prompting the evolution of resistance to and thus a loss of efficacy for the herbicide. Moreover studies indicate that genes engineered to instill resistance to herbicides can migrate to non-target crops and even related wild plants (horizontal gene transfer, transgene escape) via pollen. [10] [11] [12] [13] [14]. See also [15]. Furthermore engineered crop volunteers and weeds are even acquiring tolerances to multiple herbicides (gene-stacking) requiring ever stronger chemicals to kill [16] including "2,4D, 2,4DB, Atrazine, Paraquat, Metsulphuron Methyl, Imazethapyr". [17] This has alarmed many in the scientific community. Says the article: Cross-Pollination Leads to Triple Herbicide Resistance [18]: One of the risks frequently cited in association with transgenic crops is the escape of a foreign gene via sexual reproduction. The recipient plant in such cases may be a non-transgenic variety of the same crop or a sexually compatible relative. Depending on the gene and trait considered, adverse environmental or agricultural impacts may result from such transfers, ranging from issues of genetic purity of neighboring crops to the generation of "super weeds." While this issue is receiving increasing attention by researchers, a recent report by Hall et al. [3] describes a truly remarkable example of herbicide resistance transfer via pollen among Brassica napus [field mustard] varieties. What is unusual here is not so much that it happened at all, but that it occurred rapidly and multiple times, such that, through completely random crossing, certain plants were found to be resistant to three different herbicides. See also [19] Regarding the need for more study of this Paul E. Arriola, Associate Professor of Biology at Elmhurst College in Elmhurst, Illinois said in a personal correspondence "Scientists expressing concern about negative consequences for wide scale GM release have recommended for years that GM producing companies make available probes that could be used for long-term monitoring, but the call has fallen on deaf ears in both industry and the federal government". Providing appropriate genetic probes would, he says "violate company policy" regarding Monsanto's "confidential business information" and thus "it is not likely to happen". There is now an attempt to verify worldwide how bad the problem of herbicide resistance has become. WeedScience documents (so far) "287 Resistant Biotypes, 172 Species (102 dicots and 70 monocots) and over 270,000 fields" [20] [21] [22]. Most of the resistances here are due to herbicide overuse in general however because those weeds tolerant of Roundup are closely associated with our food supply and the because of the ubiquity of Roundup Ready crops they are a particular concern. According to this site the 2003 total for GE crops was 167.2 million acres and says Monsanto "The potential for expansion for Roundup Ready crops also is significant.... For example, Roundup Ready corn currently is used on 3 million acres, but the global potential is more than 200 million acres." [23] According to Carl Casale Vice President of Monsanto the land area in the United States used for cultivation of RR crops in 2002 "increased from 3 million U.S. acres in 1996 to more than 97 million U.S. acres" [24]. While glyphosate has been marketed for nearly 30 years, its use in placing significant selection pressure on major weeds has only been since the introduction of RR soybeans in 1996. In six short years, since the introduction of RR crops, the use of glyphosate has grown 2.5 times, and in the Midwest, its use has increased even more. Some 33 million pounds of glyphosate were sprayed on soybean crops alone in 2001, a five-fold increase from 1995, according to the U.S. Department of Agriculture. Yet no matter how well glyphosate controls weeds today, take note: resistance is happening. Almost all weed scientists agree the increasing evolution of resistant biotypes is inevitable with the current use pattern of glyphosate. Their warning: increased adoption of a rotation relying solely on RR crops will contribute to the rate at which resistance evolves. [25] The explosion in the adoption of glyphosate-resistant crops outpaces any other adoption of technology in modern history (including the tractor, fertilizer and hybrid corn). [26] Monsanto also came under heavy public fire with their "Terminator Technology" in which they developed and planned to market seeds that, after one season's growth would not germinate again forcing farmers around the world to buy their seed from them every year rather than saving their best seed for the next years planting, a traditional and economical practice. Seed saving has had the benefit of allowing farmers to continually improve the quality of their crops through careful artificial selection. Fears were also expressed that Monsanto's terminator genes could spread to wild plants. In 1999 Monsanto called the program off, however there are disturbing indications that they may be planning to resurrect it. [27] Monsanto was at the center of controversy when they employed the services of a firm called Bivings Group which used a phony e-mail campaign to persuade Nature to retract the Chapela and Quist paper finding that GM maize had escaped into Mexico.[28][29] Chapela and Quist have since been vindicated as it turns out that GM maize has indeed invaded Mexico. Says Science 3/1/2002 "Surprisingly, even Quist and Chapela's most strident critics agree with one of their central points: Illicit transgenic maize may well be growing in Mexico.... At a 23 January meeting in Mexico City, CINVESTAV official Elleli Huerta presented preliminary PCR findings indicating that transgenic promoters, mostly CaMV 35S, were present in about 12% of the plants. In some areas, up to 35.8% of the grain contained foreign sequences, INE scientific adviser Sol Ortiz Garcia told Science last week." Also [30] Monsanto has sued farmers when their GM crops have turned up on the farmer's fields even though the farmers say they never planted them [31] [32][33]. In the well known Percy Schmeiser case the Canadian Supreme Court in Monsanto v Schmeiser rejected Schmeiser's claim that the presence of RR crops had happened accidentally. Schmeiser was not required to pay Monsanto any damages, however, due to the fact that he had not profited from the infringement. Nevertheless what is disturbing to many is the fact that, though technically the court attempted to limit Monsanto's patent protection to its engineered gene, in effect the court allowed Monsanto to claim patent ownership of a plant, a form of life [34]. "Mr. Schmeiser saved the seed and reused it 'for production and advantage,' the majority noted. 'Whether or not patent protection for the gene and the cell extends to activities involving the plant is not relevant to the patent's validity'" "The team of dissenting judges in the latest decision, led by Justice Louise Arbour, said the ruling contradicts the Harvard mouse judgment. The majority is effectively allowing Monsanto 'to do indirectly what Canadian patent law has not allowed them to do directly: namely, to acquire patent protection over whole plants,' wrote Arbour" [35] [36] [37] #108 [38] [39]. The judgment along with previous ones upon which it was built has been interpreted by many to mean that if any RR crop is found on agricultural land wherein it was not specifically purchased even if it found its way there through entirely natural means such as wind or insect pollination, the farmer is liable to Monsanto for "theft" of its property. That at least seems to be the goal of Monsanto. Says this 2000 ENS article regarding the Canadian federal court judgment, "Monsanto did not directly try to explain how the Roundup Ready seed got there. 'Whether Mr. Schmeiser knew of the matter or not matters not at all,' said Roger Hughes, a Monsanto attorney quoted by the Western Producer, a Canadian agriculture magazine.... 'It was a very frightening thing, because they said it doesn't matter how it gets into a farmer's field; it's their property," Schmeiser said, in an interview with Agweek. "If it gets in by wind or cross-pollination, that doesn't matter'" [40]. "Monsanto's Jordan said the company isn't concerned that Schmeiser won't have to pay. "The important aspect of this particular case was intellectual property, not any sort of monetary gain," she said. "The ruling affirms the way that we do business" [41]. For a different assessment of the decision see here. Monsanto also recently made news when it decided to withdraw its GM wheat from the market due to worldwide opposition. [42] An issue of growing concern is the Campaign to Label Genetically Engineered Foods [43]. Many have questioned why it is that while consumers in Europe have the right to know through labeling which foods contain GM ingredients and thus to make an informed choice consumers in the United States, purportedly the bastion of the freedom and the democracy in the world are denied this same right. Attempts to accomplish some kind of labeling have repeatedly been rebuffed due to tremendous opposition from biotech which fear loss of sales if people know [44] [45]. In 2002 Oregon tried and failed to pass just such a labeling initiative (Measure 27). The campaign cited big money and misinformation propagated by biotech as contributing to the defeat [46]. (1) Monsanto was accused of fraud in assessing the risks of dioxin, a by-product of Agent Orange manufacture. Regarding this William Sanjour Policy Analyst at the EPA wrote "This kind of cold-blooded analysis is bad enough when the product is used by the general public, but it is insufferable when used on our own armed forces who were exposed in combat.... The issue wasn't false science, but allegedly using false science to cover-up a callous hard-hearted decision to continue poisoning our GIs and their children because it was cheaper to do so." [47] (2)Glyphosate products such as "Rodeo" and "Accord" along with a long list of other herbicides, are also applied liberally by local governments to aquatic environments such as streams, rivers, ponds, lakes and reservoirs often simply because such plants are deemed 'aesthetically undesirable'. A shortened list. (3) Hall L, Topinka K, Huffman J, Davis L, and Good A. 2000. Pollen flow between herbicide-resistant Brassica napus is the cause of multiple-resistant B. napus volunteers. Weed Science 48: 688-694 "Monsanto should not have to vouchsafe the safety of biotech food. Our interest is in selling as much of it as possible. Assuring its safety is the F.D.A.'s job." - Phil Angell, Monsanto's director of corporate communications. "Playing God in the Garden" New York Times Magazine, October 25, 1998. Source: http://www.disinfopedia.org/wiki.phtml?title=Monsanto Background article Jim Westwood One of the risks frequently cited in association with transgenic crops is the escape of a foreign gene via sexual reproduction. The recipient plant in such cases may be a non-transgenic variety of the same crop or a sexually compatible relative. Depending on the gene and trait considered, adverse environmental or agricultural impacts may result from such transfers, ranging from issues of genetic purity of neighboring crops to the generation of "super weeds." While this issue is receiving increasing attention by researchers, a recent report by Hall et al.1 describes a truly remarkable example of herbicide resistance transfer via pollen among Brassica napus varieties. What is unusual here is not so much that it happened at all, but that it occurred rapidly and multiple times, such that, through completely random crossing, certain plants were found to be resistant to three different herbicides. The problem The events that precipitated this study occurred in Alberta, Canada where in 1997 a producer planted three varieties of B. napus in the same or adjacent fields. One variety was resistant to glyphosate, another was resistant to glufosinate, and a third resistant to herbicides of the imidazolinone type. In field 1, the producer started planting glufosinate-resistant B. napus, but, after 15 hectares had been sowed, switched to imidazolinone-resistant B. napus for the remainder of the field. In field 2, which was located across a road (22 m from the edge of field 1 containing the glufosinate-resistant plants), the producer planted glyphosate-resistant B. napus. The next year, the producer fallowed field 1 and planted part of field 2 with imidazolinone-resistant B. napus. Weeds in the fallowed field 1 were sprayed with glyphosate, but the producer noticed that B. napus volunteers in this field were not being controlled by the herbicide. At this point, Hall and company stepped in and surveyed field 1 to determine whether herbicide resistance had developed. They collected B. napus volunteers that had survived the glyphosate treatments and grew them in the greenhouse in order to obtain seeds for further study. The resulting generation was then tested for resistance to glyphosate by spraying seedlings with the herbicide. They found that 20 of 34 individuals tested had a high percentage of offspring showing resistance to glyphosate. This result could be accounted for by either of two mechanisms: 1) direct movement of glyphosate-resistant seeds from field 2 across the road to field 1 (most likely transported by farm equipment), or 2) movement of pollen such that cross-hybridizations occurred between the glyphosate-resistant variety and either the glufosinate- or imidazolinone-resistant varieties. Although mechanical operations (planting and harvesting) in the two different fields were not performed at the same time, the direct movement of seed from field 2 to field 1 remained a possibility. Evaluation of glyphosate-resistant volunteers To confirm whether pollen flow was responsible for the glyphosate resistance, Hall et al. set forth three tests. First, if the volunteer plants had gained glyphosate resistance through pollen flow, this would have been conferred by the male parent, while glufosinate or imidazolinone resistance would have been inherited from the maternal plant. Thus, they would be resistant to two herbicides rather than just one. Second, if the resistance trait had been transferred via pollen, the progeny of the resistant plants would show a pattern of segregation for resistance consistent with Mendelian ratios for a single-locus dominant trait. Third, RFLP analysis of the progeny using markers specific for each of the parental lines would indicate whether the volunteer plants were products of a hybridization of two lines. Eight volunteer B. napus plants were put through these tests and seven passed them all, demonstrating that gene flow via pollen was the primary mechanism of resistance transfer. Progeny of additional plants were characterized solely on the basis of resistance to herbicides. In the section of field 1 originally planted with glufosinate-resistant B. napus, all nine plants tested had progeny resistant to both glyphosate and glufosinate. In the section planted with imidazolinone-resistant plants, the progeny of 10 of 11 plants were resistant to both glyphosate and the imidazolinone herbicide, imazethapyr (the lone exception to this being a glufosinate-resistant individual that was likely moved as a seed from the nearby glufosinate resistant section of the field). Triple resistance In addition to the cases of double resistance, two plants from field 1 gave rise to progeny resistant to all three herbicides. This was attributed to sequential hybridization among the plants. In one such case it is probable that a glufosinate-resistant plant was pollinated by a glyphosate-resistant plant in 1997. The following year, a progeny of this plant was selected by application of glyphosate to kill competing vegetation and was subsequently cross-pollinated by imidazolinone-resistant B. napus planted in field 2 in 1998. The triple resistance in the second plant is proposed to have arisen by a different sequence of events, with the first cross occurring between glufosinate- and imidazolinone-resistant plants. A progeny of this cross is thought to have escaped glyphosate treatment and crossed with one of the glyphosate-resistant volunteers. Although the end result is the same, this illustrates how all possible combinations and sequences of events are possible. Lessons from this situation This report demonstrates that pollen flow among individuals of an outcrossing species can be a very effective method for transmitting genes. B. napus is capable of both selfing and outcrossing, having an outcrossing frequency of 20-30%. In the field, the actual cross-hybridization rate is a function of distance, with percent outcrossing diminishing the farther the recipient is from the pollen source. It is therefore interesting that one of the triple-resistant plants was found over 550 m from the pollen sources, greatly exceeding the 100-m buffer mandated for seed producers. Also, in cases such as this field situation where large numbers of plants are involved, even a low percentage of outcrossing can result in significant transfer of genes via pollen. It is important to note that this research is dealing with intraspecific hybridization. Hybridization between Brassica crops and several wild relatives has been reported, but may occur at lower frequencies and hybrid plants may suffer from lack of vigor or fertility. The authors point out that the circumstances that gave rise to the triple-resistant B. napus are highly unusual in that three varieties harboring different herbicide-resistance genes were planted in close proximity in the same year. Then the next year the only weed control method used in the fallowed field 1 was the herbicide glyphosate. B. napus is susceptible to many weed control measures, so in the second year the glyphosate-resistant volunteers should properly have been controlled by herbicides with different modes of action, tillage operations, or cultural practices. Fortunately, seeds of B. napus have a relatively short persistence (duration of dormancy of four to five years in the soil) so proper management practices will eliminate multiple-resistant weed seeds in a relatively short period of time. Nevertheless, this report points out just how rapidly genes can move within an outcrossing crop and why planting distance and crop rotation precautions and herbicide/weed control techniques need to be varied regularly to avoid developing problematic volunteer weeds. (For more information, see "Outcrossing Between Canola Varieties - A Volunteer Canola Control Issue" at < http://www.agric. gov.ab.ca/crops/canola/outcrossing.html >.) This example should serve as a warning to producers to use their new herbicide-resistant crops wisely according to guidelines. Source: The above article is reference by Monsanto at http://www.monsanto.com/monsanto/content/our_pledge/transparency/prod_safety/roundup_canola/prsp.pdf | |
