Ethiopia goes organic to feed herself - The Institute of Science In ...

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40 Technology Watch Bio-remediation Without Caution A bacterium living inside plants could be improved for cleaning up environmental pollutants without genetic modification. Prof. Joe Cummins and Dr. Mae-Wan Ho reveal that this seemingly beneficial development is beset with danger, as the bacterium concerned is a known pathogen. Water soluble and highly volatile organic environmental pollutants, such as benzene, toluene, ethylbenzene and xylene compounds, chlorinated solvents and nitrotoluene ammunition wastes, are being cleaned up using plants in combination with microorganisms that naturally live inside the plants (endophytes). Endophyte bacteria live within the tissue of the plant without harming it. They are found in most plant species, and many can colonize the vascular system. The highest densities of bacteria are usually found in the roots, less in the stem, and least in the leaves. The plants take up the pollutants through their roots, and the bacteria break these down within the roots or in other parts of the plant. This natural process is inefficient because the compounds tend to get transported up the plant faster than the bacteria can break them down. Once transported up, the plants metabolize the contaminants, and some of the metabolites as well as the contaminant can be toxic. For example, trichloroethane is metabolized into trichloroacetic acid, both of which are toxic. Worse still, plants tend to release volatile pollutants and their metabolites into the atmosphere via evaporation from the leaves, which turns bio-remediation into bio-pollution. A recent article in Nature Biotechnology reports how this clean up process could be greatly improved by engineering an endophyte bacterium Burkholderia cepacia, a natural resident of the yellow lupine. Researchers from Linburgs University in Diepenbeek, Belgium and Brookhaven National Laboratory in New York, USA, created a strain of B. cepacia that has enhanced ability to degrade toluene within the plant, enabling the plant to tolerate high levels of toluene, and also substantially reduced the amount of toluene released into the atmosphere. The engineered strain of the bacterium carries marker genes for kanamycin resistance and nickel resistance and is derived from the natural endophyte. By adding to this endophyte strain a toluene-degrading plasmid from another strain of B. cepacia that normally lives in the soil through natural conjugation (bacterial reproduction) between the strains, a new endophyte strain is created that can live in the plant and degrade toluene taken up by the plant. Plants inoculated with the engineered bacterium grew much better than plants that were not inoculated; or else inoculated either with the control strain lacking the plasmid, or with the strain that normally lives in the soil. More impressively, the plants inoculated with SCIENCE IN SOCIETY 23, AUTUMN 2004 the engineered bacterium reduced toluene evaporation into the atmosphere to about 50% of the control. This looks very promising, and as the researchers point out, the experiment could have been done without any genetic modification. The plasmid containing all the toluene degrading enzymes belonged to a natural soil bacterium, and an endophyte host without the marker genes could easily have been used to receive the plasmid by conjugation. A non-GM bacterial endophytic strain created in this way may well be the very first really useful and beneficial product from the industry. So what's wrong? The research paper did not deal with safety. What metabolites of toluene are generated in the plant, and will they be toxic? How will the plants be disposed of? There are three lupine species cultivated for fodder - blue, white and yellow - and there are also a number of wild species. The wild species contain alkaloid chemicals that are very toxic to cattle and sheep while the cultivated species are edible for farm animals, provided care is taken to treat the seeds in such a way as to remove the toxins. Lupines thrive on poor soil and provide ground cover and green manure as well as fodder for animals. More importantly, the research report failed to mention that B. cepacia has the ability to cause fatal disease in humans. The groundwater of Wichita, Kansas was found to be polluted with the chemical solvents dichloroethylene and trichloroethylene, and was cleaned up using a natural strain of B. cepacia. But no special public health measures or follow up seemed to have been implemented after the clean up. The United States Environmental Protection Agency (EPA) has considered the problems associated with approval of B. cepacia as a plant pesticide, for, not only is the bacterium used to fight plant pests but is itself a pest as it is a disease agent in humans. EPA, through a Scientific Advisory Panel (SAP), reviewed B. cepacia as a plant pesticide and acknowledged that it is linked to human disease. The SAP risk assessment peculiarly noted, "Bc [B. cepacia] has been referred to as an opportunistic human pathogen. However, as might be expected, the strains registered or proposed for use as biopesticides were isolated from the soil or plant roots, rather than from human patients". In reality, the SAP comment offered cold comfort because the B. cepacia strains isolated from patients proved essentially undistinguishable from strains isolated from the roots of crops such as corn. The American Phytopathological Society produced a useful review of the risks from plant disease or human disease along with the benefits in cleaning up chemical pollution and fighting some plant diseases. Unfortunately, there has been no clear and simple way to differentiate between the 'evil' and the beneficial strains of B. cepacia, and no way of preventing the two from exchanging genes. B. cepacia has an unusual genetic makeup; it has a relatively large amount of DNA (about twice that of E. coli) and unlike most bacteria, which usually have a single chromosome, B. cepacia strains have as many as five large replicons (chromosomes) and the different chromosomes are rich in insertion sequences that allow for extensive gene exchange between different strains, and insertion of disease related genes from other bacterial species. B. cepacia is a prominent cause of death among cystic fibrosis patients, the bacterium frequently reaches epidemic proportions among such patients and an epidemic related strain was identified in soil samples in the USA. It is believed to be a complex species made up of seven distinct genomic subspecies all of which are capable of infecting humans; and all of the diseaserelated subspecies were isolated from maize rhizosphere (root zone). The disease is difficult to contain because disease bacteria may be replenished continually from the soil and plant material. Hospital acquired B. cepacia epidemics appeared among patients with diabetes, malignancy, heart failure and chronic obstructive pulmonary disease. One such B. cepacia outbreak appeared in an intensive pediatric care unit, and B. cepacia infection was common among renal transplant patients. Different B. cepacia clones showed different infectivity among cystic fibrosis patients and patients with different complaints. Antibiotic resistant B. cepacia infection was the most common cause of death among lung transplants for cystic fibrosis patients. B. cepacia causes feared infections because the strains tend to be antibiotic resistant. Bacteria isolated from different infections were found to be resistant to all seven tested antibiotics but were sensitive to treatment with honey. Do lupines pose a threat to people with compromised immune systems or cystic fibrosis? Yellow lupines, and perhaps the other commercial species as well, contain potentially disease-causing B. cepacia endophytes, so their presence in hospitals and homes of compromised people is unwise. The bacteria may be transferred by direct contact with broken plant stems or petals along with the dust and debris associated with the plant; a gift of lupines could be fatal. There is clearly a large literature on the threat of B. cepacia infection and its death toll among compromised patients. The existing evidence indicates that the bacterial infections may pass from the ecosystem to the hospital ward and there seems no way of ensuring that the B. cepacia strains used in biotechnology are unable to infect compromised humans. SiS
ISP News 41 ISP to FAO: GM Crops Not the Answer Lim Li Ching reports The Independent Science Panel (ISP) (www.indsp.org) has criticised the Food and Agriculture Organization (FAO) of the United Nations for its qualified backing of genetically modified (GM) crops in the global fight against hunger. The FAO recently released its annual publication, The State of Food and Agriculture 2003-2004. This year, the theme was on "Agricultural Biotechnology: Meeting the needs of the poor?" The report touches on the full range of agricultural biotechnology tools and applications, but focuses largely on transgenic or GM crops and their impact on poor people in poor countries. While acknowledging that biotechnology is not a panacea, the FAO maintains that it holds great promise as a new scientific tool for generating applied agricultural technologies. The report claims that biotechnology is capable of benefiting small, resource-poor farmers, yet also cautions, "Given that technologies that are on the shelf today (generated by conventional research methods) have not yet reached the poorest farmers' fields, there is no guarantee that the new biotechnologies will fare any better." Thus, the FAO seems to ignore the implicit message of its own study: GM crops have thus far delivered negligible benefits to the world's poor. And there is little indication that these trends will change in favour of the poor. As the report points out, crops and agronomic traits of importance to developing countries and marginal production areas have been ignored. Instead, the focus has been on four crops (soybean, maize, cotton, canola) more suited for industrial agriculture and unlikely to meet the food security needs of poor farmers, and two traits (herbicide tolerance and insect resistance) of limited relevance; herbicide resistance, in particular, is less relevant for developing countries where farm labour is abundant. These four crops and two traits have, however, been the mainstay of the GM industry, controlled largely by transnational corporations that have reaped most of the benefits. This private sector-led investment in agricultural research and development depends on strong protection of intellectual property rights (IPRs) over GM crops. The FAO is disingenuous when it calls on countries to develop stronger IPR regimes to promote GM crop research, even as the independent Commission on Intellectual Property Rights has expressed reservations over patent protection for plants and animals. Many developing countries that are World Trade Organisation (WTO) members, particularly the Africa Group, have also expressed similar concerns, joining countless non-governmental and civil society organisations, and some 700 scientists (including ISP members, see http://www.i-sis.org.uk/list.php), to call for no patents on living organisms. Is the FAO ignoring these views, much as it seems to be selective in the evidence it draws on to justify the report's conclusions? For example, in the section on public attitudes, the report relies heavily on a survey that asks imbalanced questions. This section concludes that people in developing countries are generally likely to support agricultural biotechnology, which is not surprising, given that the risks are not mentioned in the questions asked, only the potential benefits. Yet the risks of GM crops are increasingly apparent. The FAO report is unacceptably silent on the transgenic contamination of traditional varieties of maize in Mexico, a centre of origin and diversity of maize; it doesn't discuss biodiversity and food security impacts, let alone the immense implications on cultural and indigenous practices. Dr. Mae-Wan Ho, director of the Institute of Science in Society (ISIS) and member of the ISP, points to further flaws: "The FAO claims that scientists generally agree that current transgenic crops and the foods derived from them are safe to eat. But there are many scientists - ISP members included - who have questioned this premise, and there is increasing evidence that casts doubt on GM food safety." The ISP's report, The Case for a GM-Free Sustainable World, is an extensive review of the scientific and other evidence on the problems and hazards of GM crops and the manifold benefits of all forms of sustainable agriculture. It is clear, from the evidence therein, that there are many unanswered questions on the safety of GM crops. Very few studies have been conducted, particularly as to the effects of GM foods on human health. There is a dearth of published scientific papers on which a reliable database of safety can be established, and the few independent studies that have been carried out raise serious concerns. There is also increasing indication of the environmental and socio-economic impacts of GM crops, particularly on smallholder farmers. The ISP has called for a global ban on environmental release of GM crops, to make way for agroecology, organic farming and other forms of sustainable agriculture. There is growing evidence that many smallholder farmers in developing countries already have the knowledge, experience and innovative spirit that enable them to farm sustainably and productively, without depending on GM crops. These traditional farming practices best address agriculture that is complex, diverse and risk-prone; GM crops would create many more risks for these farmers. The FAO should be calling for more research into these sustainable practices, so as to better them and make them equitably accessible, rather than into GM crops. If the world is to seriously address hunger, this means rethinking agriculture and associated policy making, and exploring how traditional knowledge and science can work together, while learning from farmers themselves. World hunger today is more a consequence of economic and political forces that hamper distribution, and less one of inadequate food supply. These, and other issues including access to land, water, credit and markets, the loss of agricultural biodiversity and the inequities in multilateral policies that affect agriculture and rural development, must be addressed. The FAO would do better to focus on these issues, rather than on GM crops, if it is really serious in "helping build a world without hunger". SiS www.i-sis.org.uk
Page 1 and 2: Science in Society ISSUE 23 Autumn
Page 3 and 4: From the Editor Corporations coveti
Page 5 and 6: 5 dependency ratio and although off
Page 7 and 8: 7 Figure 1. Maize yields in 5 sites
Page 9 and 10: Rice Wars 9 Fantastic Rice Yields F
Page 12 and 13: 12 New Rice for Africa Dr. Mae-Wan
Page 14 and 15: 14 Does SRI Work? The first reality
Page 16 and 17: 16 hybrid rice Liangyoupei 9, which
Page 18 and 19: ier around the field. There is a pa
Page 20 and 21: 20 Chinese researchers have develop
Page 22 and 23: 22 Two Rice Better than One Lim Li
Page 24 and 25: "Silicon Valley of agricultural bio
Page 26 and 27: 26 Approval of Bt11 Maize Endangers
Page 28 and 29: 28 Prof. Joe Cummins discovers that
Page 30 and 31: 30 Collusion and Corruption in GM P
Page 32 and 33: 32 Questions over Schmeiser's Rulin
Page 34 and 35: 34 DNA in GM Food & Feed The govern
Page 36 and 37: 36 denum of cattle. The studies wer
Page 38 and 39: Prof. Joe Cummins explains why gene
Page 42 and 43: Rethinking health Selenium Conquers
Page 44 and 45: 44 Delivering Good Health Through G
Page 46 and 47: 46 process in which new humans are
Page 48 and 49: 48 molecules in liquid, allowing ra
Page 50 and 51: 50 Water Forms Massive Exclusion Zo

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