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Published online 6 July 2009 | Nature | doi:10.1038/news.2009.629
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Pests could overcome GM cotton toxins
Caterpillars reveal a chink in the armour of transgenic crops.
Laboratory studies suggest that it may be possible for insects to overcome two disparate toxins produced by genetically modified cotton. The results strike a cautionary note at a time when developers are racing to create crops that produce many different pesticides.
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Pests evolution in race with GMOs may have been predicted given that the toxins produced by them clearly constitute a selective pressure. What worries me is when is this going to stop? If we know that evolution cannot be stopped and we also have some doubts about the ecological benefits and damages that GMOs may provoke both to the environment and beings, why don´t we stop them?
The answer to Ms Corvera's excellent query, if interpreted to mean why these organisms are not stopped or at least far more carefully regulated, strikes me as obvious - because they can be extremely profitable for a few megacorporations, who can and do buy and sell the politicians who determine what regulations are in place. Why «we» don't stop them is a different question, the answer to which probably has a lot to do with «our» lack of political and economic power - the same reasons why «we» are so bad at stopping wars and reducing the military-industrial-media complex's strangle-hold over our economies.... Henri
The most frightening consequence of resistance to compounds in GM crops is hardly ever discussed: What will happen to the natural systems where the natural bacteria who hosts these defenses reside? What happens when the source host of resistance genes becomes no longer "resistant?" I'll be the first to tell you that all ecosystems on Earth begin with Bacteria, and it's a very, very bad idea to remove certain bacteria from the environment by nullifying their natural defenses.
pest problems can only be solved if one takes an ecosystems approach, when one concentrates first in growing a healthy and strong plant, using sound agronomic practices. We ned to distance ourselves from the short sighted symptom treatments and concentrate on the causes, we need to realize that the reductionistic approach, that may work for a short while goes against all sustainability principles. The GMO approach for solving pest and weed problems is wrongheaded, and can only serve the corporations that produce them, at the expense of the farmers, consumers and in the end the environment. Its time to make use of the experience we made with pesticides and apply these to the GMOs, i.e., drop that approach which has not solved a single pest problem on a permanent and environmentally acceptable manner. I also do not want to read that unless we use GMOs, or pesticides / herbicides there will not be enough food for all, or that it would be too expensive for the poor to afford. I have worked long enough in ag research, pest management and development to now that 1. we can produce enough quality food for all (even for 9 billion people) using sustainable (organic, eco-agriculture) and 2. that the problem of hunger and poverty has to do with over consumption in some parts of the world, with inequity, that has increased with the green revolution and industrial agriculture. It has also been recognized that the industrial agriculture model is a dead end from the energy input aspect, that re climate change its part of the problem and that instead of providing healthy food, it has led to low food quality, and the cheap prices to huge wastage. For more details and additional information on the state of agriculture, please visit : www.agassessment.org. The reports available on that website represent the newest and most comprehensive analysis of the present status of agricultural Knowledge, Science and Technology and suggest that for the world to feed itself sustainably for the decades to come, there is a need to radically change course. Business as usual is not an option. Hans R Herren, Co-Chair IAASTD and President Millennium Institute
Nature has given a signal that not to play with it using modern scientific tools. More natural a scientific approach is better it will be for humanity. GMO's are not going to be solution. So better to invest scientific funding in traditional research like Plant breeding etc. So say no to GMO. Anurag chaurasia, NBAIM, ICAR, INDIA
I read with interest the review, Pests Could Overcome GM Cotton Toxins. In it, the results of a Tabashnik et al. paper were summarized, describing asymmetrical cross-resistance between the Bt proteins Cry1Ac and Cry2Ab in the important cotton pest, pink bollworm. I know this work thoroughly. As noted in the paper Acknowledgments, the research was initiated in my laboratory at the University of Arizona. The initial laboratory selection, begun with collections I made in Texas in 2001, revealed cross-resistance only after > two years of intensive exposure to Cry2Ab by paper co-author, Dr. Gopalan Unnithan. I then made the resistant strains available to my colleague and friend, Dr. Tabashnik, and he, in-turn, made it the subject of a successful NRI grant to verify and investigate the genetic basis of the cross-resistance. After I joined Monsanto?s Global Cotton Resistance Management Program in 2008, I recused myself from any role in the writing or review of this paper. > A key point that may not be appreciated is that these sorts of resistance selection experiments are the functional equivalents of race car test tracks, where autos are evaluated for performance at excessive speeds. Our goal was to create a worst-case resistance scenario. As Dr. Ferre warned, ?This is a special condition in the laboratory.? ?The important thing is to find out whether that resistance can be obtained in the field.? Continuing the test track analogy, a crash at 200 mile-per-hour obviously does not have direct bearing on the risk you encounter in normal driving. > What is undeniable at this time is that globally the resistance problems with Bt crops have been much more limited than I, or most of my academic colleagues, thought would be the case. However, only the uninformed or naive expect any given insect control measure to be free of resistance risk. In 1997, after my group isolated Arizona pink bollworm capable of surviving on Bt cotton, I participated in educational programs for cotton producers throughout Arizona, telling them of the impending resistance problems that we were pretty confident were coming. A decade of Tabashnik et al. papers have shown that we were very wrong and today that cadherin-based resistance, or any other resistance, cannot be detected in the Southwest in pink bollworm. Field resistance dynamics and expression of resistance under field conditions are much more complicated and unpredictable than we previously thought. > Thus, the 'chink in the armour of transgenic crops' as it was described by Ms Ledford, was created in the laboratory under highly unusual selection conditions and is of no relevance to field strains of pink bollworm that we can tell at this time. There is no scientific basis for interpreting it as something that fundamentally erodes the reduced resistance risk gained by pyramiding of Bt proteins. Moreover, as Tabashnik et al. state, there are other important factors thwarting resistance in concert with pyramids of Bt proteins, perhaps the most prominent of which is refuges of non-Bt host plants near Bt crops. We know that all insect control measures are at risk of resistance. Our science and practice continues to be aimed aggressively at delaying and postponing resistance as long as practical so that we can continue to garner the benefits of biorational insect control tactics like Bt crops.
GMO field trial in India is totally nonserious in nature. As myself has conducted first field trial of Transgenic tomato, brinzal in IARI, ICAR system.No seriousness i could observe in DBT, ICAR etc.Crops ofsame family is being grown together.May insects are developing resistance but things are being ignored. Infact i feel multinational like Monsanto is using India for field & human trial of GMO. India are being used as guinea pig. Top govt officials are just a playcard in the hand of these companies. Even many of us are joining these companies after taking VRS. As Prof Raina NRCPB, IARI joined MNC along with transgenic material developed in the Govt secter. So it's a time that we all from scientific comunity should stop being used as playcard in the hand of these MNC & should think about nature & humanity above our personal gain. SO SAY NO TO GMO & be NATURAL keep Nature alive. Anurag chaurasia, NBAIM, ICAR, India
The best strategy of crop pest management is implementation of ecological agriculture, involving crop varietal mixture, enhancing on-farm biodiversity (by planting diverse plants to encourage predator species diversity and abundance) and crop rotation.
I have been practising and demonstrating the efficacy of ecological agriculture on my farm Basudha (www.cintdis.otg/basudha.html) over the past decade, and growing 610 folk rice varieties in situ, without the need of application of a single dose of any pesticide. The recent IAASTD report, as mentioned by Dr. Hans Herren above, amply corroborates this experience, and cites a plethora of cross-country evidence. However, as the UNDP's Human Development Report (1999) observed, "money talks louder than science" and good sense, and therefore GM crops are promoted, while FAO remains silent about the IAASTD report.
Debal Deb
Centre for Interdisciplinary Studies, Barrackpore, India (Current address: ERG, University of California- Berkeley) debaldeb@wildmail.com