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The Case Against Agricultural Biotechnology

by Miguel A. Altiericontained in a briefing packet that was sent to ministers of the Sacramento Ministerial
June 10th, 2003

The deployment of transgenic crops is occurring at a rapid pace, reaching about 44.5 million hectares in 2000. Although commercial cultivation is mostly confined to USA, Argentina, Canada, and China, biotechnology proponents argue that expansion of such crops to the Third World is essential to feed the poor in the Third World, reduce environmental degradation, and promote sustainable agriculture. Such promises do not match reality.

Biotechnology is a technology under corporate control, protected by patents and IPR, and thus contrary to farmers' millenary traditions of saving and exchanging seeds.

Hunger is linked to poverty, lack of access to land, and maldistribution of food. Biotechnology exacerbates inequalities underlying the causes of hunger.

Transgenic crops pose a range of potential environmental risks that threaten the sustainability of small farming systems. The ecological effects of engineered crops are not limited to pest resistance and creation of new weeds and pollution of landraces. Transgenic crops can produce environmental toxins that move through the food chain, and also may end up in the soil and water affecting invertebrates, and probably ecological processes such as nutrient cycling. Moreover, large-scale landscape homogenisation with transgenic crops will exacerbate the ecological vulnerability already associated with monoculture agriculture (Altieri 2000a).

There is widespread consensus that yields have not increased with transgenic crops. In the case of Bt corn the economic advantages are not clear, given that the occurrence of insect pests is unpredictable.

Savings in insecticide use are minimal when examined on a per hectare basis, and insignificant when compared to savings derived from Integrated Pest Management strategies. Herbicide use is up, locking farmers to broad spectrum herbicides that narrow weed management options and condemn farmers to monoculture.

There are agroecological alternatives to biotechnology that result in technologies that are cheap, accessible, risk averting, productive in marginal environments, environment and health enhancing, and culturally and socially acceptable.

Policies must be put in place to promote the upscaling of successful agroecological interventions, that are already reaching about nine million small farmers at one-tenth the cost incurred by official international agricultural subventions.

It is urgent that international donors recognise the gravity of the problem, take a chance on new institutional arrangements led by NGOs and farmers' organisations, and provide funding for a grassroots-based alternative agricultural development approach in the Third World.

Biotechnology companies often claim that genetically modified organisms (GMOs) - specifically genetically altered seeds - are essential scientific breakthroughs needed to feed the world and reduce poverty in developing countries. Such claims promoted by the biotech industry-created consortium, the 'Council for Biotechnology Information' with a $250 million budget, uses the issue of hunger in the developing world to justify GM crops without explaining how GM crops will actually mitigate hunger. Malthusian biotechnologists need first to explain why GM crops will feed hungry Indians when 36.6 million excess tons of grain stocks in 'godowns' (silos) of India will not. The world today produces more food per inhabitant than ever before. Enough food is available to provide 4.3 pounds for every person every day: 2.5 pounds of grain, beans, and nuts, about a pound of meat, milk, and eggs, and another of fruits and vegetables (Lapp et al.. 1998). Simply raising food output may be the last thing that is needed.

In 1999 enough grain was produced globally to feed a population of eight billion people (six billion inhabit the planet in 2000), had it been evenly distributed or not fed to animals. Seven out of ten pounds of grain are fed to animals in the USA. Countries such as Brazil, Paraguay, Thailand, and Indonesia devote thousands of acres of agricultural land to produce soybeans and manioc for export to feed cattle in Europe. By channelling one-third of the grain produced world-wide to needy people, hunger would cease instantly (Lapp et al.. 1998). Hunger is also compounded by globalisation, especially when developing countries embrace free trade policies (lowering tariffs and allowing goods from industrialised countries to flow in) advocated by international lending agencies. The experience of Haiti, one of the world's poorest countries, is illuminating. In 1986 Haiti imported just 7,000 tons of rice, the majority consumed was grown in the island. After opening its economy to the world, cheaper rice immediately flooded in from the USA where the rice industry is subsidised. By 1996 Haiti imported 196,000 tons of foreign rice at the cost of US$100 million a year. Haitian rice production became negligible once dependence on foreign rice was complete, and the cost of rice rose, leaving large numbers of poor people at the whim of rising world grain prices. Hunger increased (Aristide 2000).

The real causes of hunger are poverty, inequality, and lack of access to food and land. Too many people are too poor (about two billion survive on less than a dollar a day) to buy the food that is available but often poorly distributed, or lack the land and resources to grow it themselves (Lapp et al.. 1998). Because the true root cause of hunger is inequality, any method of boosting food production that deepens inequality is bound to fail to reduce hunger.

By matching myth with reality this paper challenges the false promises made by the genetic engineering industry that it will move agriculture away from a dependence on chemical inputs, increase productivity, decrease input costs, help reduce environmental problems, and feed the hungry (Office of Technology Assessment 1992). By challenging the myths of biotechnology we can expose genetic engineering for what it really is: another 'technological fix' or 'magic bullet' aimed at circumventing the environmental problems of agriculture (which themselves are the outcome of an earlier round of technological fix) without questioning the flawed assumptions that gave rise to the problems in the first place (Hindmarsh 1991). Biotechnology develops single-gene solutions for problems that derive from ecologically unstable monoculture systems designed on industrial models of efficiency. Such a unilateral and reductionist approach was already proven ecologically unsound for pesticides, also promoted by the same biotech firms, with a reductionist approach using one chemical-one pest as opposed to the one gene-one pest approach now promoted by biotechnology.

Modern industrial agriculture, today epitomised by biotechnology, is founded on philosophical premises that are fundamentally flawed, and these premises are precisely the ones that need to be exposed and criticised in order to advance towards a truly sustainable agriculture. This is particularly relevant in the case of biotechnology, where the alliance of reductionist science and multinational monopolistic industry will take agriculture further down a misguided route, jointly perceiving agricultural problems as genetic deficiencies of organisms, and treating nature as a commodity while in the process making farmers more dependent on an agribusiness sector that increasingly concentrates power over the food system.

Will biotechnology benefit poor farmers?

Most biotechnological innovations available today bypass poor farmers: first because these farmers cannot afford the seeds that are protected by patents owned by biotechnology corporations, and second, because this modern technology is not adapted to the marginal environments where resource-poor farmers live. An estimated 850 million people live on land threatened by desertification. Another 500 million reside on terrain that is too steep to cultivate. Because of these and other limitations, about two billion people have been untouched by modern agricultural science. Moreover, most of the rural poor live in the tropics, a region that will be most vulnerable to the effects of global warming (Conway 1997).

Biotechnology researchers pledge to counter problems associated with food production in such marginal areas by developing GM crops with traits considered desirable for small farmers, such as enhanced competitiveness against weeds, and drought tolerance. However, agricultural biotechnology innovations (i.e. Bt crops and herbicide resistant crops) are profit-driven rather than need-driven. The real thrust of the genetic engineering industry is not to make agriculture more productive but to generate profits (Busch et al.. 1990). In the case of herbicide tolerance the goal is to win greater herbicide market-share for a proprietary product, and to boost seed sales at the cost of damaging the usefulness of a key pest management product (Bt) that is relied on as an alternative to insecticides.

Even if biotechnology contributes to increased harvests poverty will not necessarily decline. Many poor farmers in developing countries do not have access to cash, credit, technical assistance, or markets. The so-called Green Revolution of the 1950s and 1960s bypassed such farmers because planting the new high-yield crops, and maintaining them through the use of pesticides and fertilisers, was too costly for impoverished landowners. Data show that in both Asia and Latin America wealthy farmers with larger and better-endowed lands profited from the Green Revolution, whereas farmers with fewer resources often gained little (Lapp et al. 1998). The 'Gene Revolution' might only end up repeating the mistakes of its predecessor. Genetically modified seeds are under corporate control and patent protection, consequently they are very expensive. Since many developing countries still lack the institutional infrastructure and low-interest credit necessary to deliver these new seeds to poor farmers, biotechnology will only exacerbate marginalisation.

Moreover, poor farmers do not fit into the profitable marketing niche of private corporations, whose focus is on biotechnological innovations for the commercial-agricultural sectors of industrial and developing nations. The private sector often ignores important crops such as cassava, which is a staple for 500 million people world-wide. The few impoverished landowners who will have access to biotechnology will become dangerously dependent on the annual purchase of genetically modified seeds. These farmers will have to abide by onerous intellectual property agreements not to plant seeds yielded from a harvest of bioengineered plants. In the USA farmers adopting transgenic soybeans must sign an agreement with Monsanto. If they sow transgenic soybeans the next year, the penalty is about $3,000 per acre and, depending on the acreage, could cost farmers their farms, their livelihood. By controlling germplasm from seed to sale, and by forcing farmers to pay inflated prices for seed-chemical packages, companies are determined to extract the most profit from their investment (Krimsky and Wrubel 1996).

What about Golden Rice?

Scientists who support biotechnology and disagree with the assertion that most biotechnology research is profit- rather than need-driven, use the newly-developed but not yet commercialised Golden Rice to hide behind a rhetoric of humanitarianism. This experimental rice is rich in beta-carotene, an important nutrient for millions of children, especially in Asia, suffering from Vitamin A deficiency that can lead to blindness.

The suggestion that genetically altered rice is the proper way to address the condition of two million children at risk of Vitamin A deficiency-induced blindness reveals a tremendous naivet about the real causes of vitamin and micronutrient malnutrition. Vitamin A deficiency cannot really be characterised as a problem, but rather as a symptom. It warns us of broader inadequacies associated with both poverty, and with agricultural change form diverse cropping systems toward rice monoculture promoted by the Green Revolution. People do not exhibit Vitamin A deficiency because rice contains too little Vitamin A, or beta-carotene, but rather because their diet has been reduced to rice and almost nothing else. These people suffer from many other dietary illnesses that cannot be addressed by beta-carotene, but which could be addressed, together with Vitamin A deficiency, by a more varied diet. Golden Rice must be seen as a one-dimensional attempt to fix a problem created by the Green Revolution: the problem of diminished crop and dietary diversity. A magic-bullet solution, which places beta-carotene into rice while leaving poverty, poor diets, and extensive monoculture intact, is unlikely to make any durable contribution to well-being. When leafy plants are re-introduced into the diet of poor people they provide both needed beta-carotene and other missing vitamins and micro-nutrients, providing a meaningful addition to peasant nutrition and subsistence. There is an abundance of wild and cultivated green leafy vegetables rich in vitamins and nutrients within and on the periphery of paddy rice fields, most of which are eliminated when farmers adopt monocultures and associated herbicides (Greenland 1997).

Rice biotechnologists have no understanding of the deeply-rooted cultural traditions that determine food preferences among Asian people, especially the social and even religious significance of white rice. It is highly unlikely that the Golden Rice will replace white rice, which for millennia has played a variety of nutritional, culinary, and ceremonial roles. No doubt Golden Rice will clash with traditions associated with white rice, as green or blue French fries would clash with Western food preferences in the USA or Europe.

But even if Golden Rice made it into the bowls of poor Asians, there is no guarantee that it would benefit poor people who don't eat fat-rich or oil-rich foods. Beta-carotene is fat-soluble and its uptake in the intestine depends upon fat or oil in the diet. People suffering protein-related malnutrition and lacking dietary fats and oils cannot store Vitamin A well in the liver, nor transport it to the different body tissues where the vitamin is needed. Moreover, given the low concentration of beta-carotene in the miracle rice (about 1.5 mg/gr of dry weight), people would have to eat more then one kilogram of rice per day to obtain a recommended daily allowance dose of Vitamin A.

Does biotechnology increase yields?

A major argument advanced by biotechnology proponents is that transgenic crops will significantly boost crop yields. Data from the USA do not support such claims. Yields have not increased with transgenic crops, rather, soybean yields tend to be lower (about six per cent less) when compared with conventional varieties, cotton yields have remained unchanged, and maize yields are higher only under sporadic conditions of high pest-pressure. No biotechnological breakthrough of resource-poor farmers has been recorded, and there is no GM crop on the horizon that is expected to outperform local varieties under the heterogeneous environmental conditions facing small farmers. Although data from the developing world is scarce, a US Department of Agriculture Economic Research Service report (USDA 1999) which analysed data collected in 1997 and 1998 for 12 and 18 USA region/crop combinations is very conclusive. The crops surveyed were Bt corn and cotton, and herbicide tolerant (HT) corn, cotton, and soybeans, and their non-engineered counterparts.

Some scientists and policy makers suggest that large investments through public-private partnerships can help developing countries acquire the indigenous scientific and institutional capacity to shape biotechnology to suit the needs and circumstances of small farmers. But once again, corporate intellectual property rights to genes and gene-cloning technology might play spoiler. For instance, in Brazil its national research institute (EMBRAPA) must negotiate licence agreements with nine different companies before a virus-resistant papaya developed with researchers at Cornell University can be released to poor farmers (Persley and Lantin 2000).

Environmental impacts of agricultural biotechnology

Biotechnology is being pursued in order to patch up problems (e.g. pesticide resistance, pollution, soil degradation, etc.) caused by previous agrochemical technologies promoted by the same companies now leading the biorevolution. Transgenic crops developed for pest control closely follow the paradigm of using a single control mechanism (a pesticide) that has proven to fail over and over again with insects, pathogens, and weeds (National Research Council 1996). The touted 'one gene - one pest' approach will also be easily overcome by pests that are continuously adapting to new situations and evolving detoxification mechanisms (Robinson 1996).

Agricultural systems developed with transgenic crops favour monocultures characterised by dangerously high levels of genetic homogeneity, leading to higher vulnerability of agricultural systems to biotic and abiotic stresses (Robinson 1996). By promoting monocultures it will also undermine ecological methods of farming, such as rotation and polycultures, thus exacerbating the problems of conventional agriculture (Altieri 2000a).

As the new bioengineered seeds replace and contaminate the old traditional varieties and their wild relatives, genetic erosion will accelerate in the Third World (Fowler and Mooney 1990). Thus the push for uniformity will not only destroy the diversity of genetic resources, but will also disrupt the biological complexity that underlies the sustainability of indigenous farming systems (Altieri 1996).

Impacts of herbicide resistant crops

Weed resistance

The continuous use of herbicides such as bromoxynil and glyphosate (also known as Roundup) which herbicide resistant crops tolerate can lead to problems (Goldberg 1992). It is well documented that when a single herbicide is used repeatedly on a crop, the chances of herbicide resistance developing in weed populations greatly increases (Holt et al. 1993). About 216 cases of pesticide resistance have now been reported in one or more herbicide chemical families (Holt and Le Baron 1990). Triazine herbicides have the most resistant weed species (about 60).

The problem is that given industry pressures to increase herbicide sales, acreages treated with these broad spectrum herbicides will expand, exacerbating the resistance problem. Although glyphosate is considered less prone to causing herbicide resistance in weeds, over time the increased use of the herbicide is bound to result in resistance.

Herbicides kill more than weeds

Companies affirm that bromoxynil and glyphosate, when properly applied, degrade rapidly in the soil, do not accumulate in groundwater, have no effects on non-target organisms, and leave no residue in foods. There is, however, evidence that bromoxynil causes birth defects in laboratory animals, is toxic to fish, and may cause cancer in humans (Goldberg 1992). Because bromoxynil is absorbed dermally, and because it causes birth defects in rodents, it is likely to pose hazards to farmers and farm workers. Similarly, glyphosate has been reported to be toxic to some non-target species in the soil: both to beneficial predators such as spiders, mites, carabid and coccinellid beetles, and to detritivores such as earthworms, as well as to aquatic organisms, including fish (Paoletti and Pimentel 1996). Questions about food safety also arise as this herbicide suffers little metabolic degradation in plants and is known to accumulate in fruits and tubers, and more than 37 million pounds of this herbicide are now used annually in the USA alone. Moreover, research documents that glyphosate seems to act in a similar fashion to antibiotics by altering soil biology in a yet unknown way and thus exerting effects such as :

Reducing the ability of soybeans and clover to fix nitrogen;

Rendering bean plants more vulnerable to disease;

Reducing the growth of beneficial soil-dwelling mycorrhizal fungi, which are key for helping plants extract phosphorous from the soil.

Most poor farmers rely on soil biological processes and organic matter for soil fertility, thus altering microbial populations with herbicides can make them more dependent on fertilisers, an expensive outcome.

Creation of 'superweeds' and contamination of landraces

Although there is some concern that transgenic crops themselves might become weeds, a major ecological risk is that large scale releases of transgenic crops may promote transfer of transgenes from crops to other plants, which then could become weeds but also unleash unpredictable ecological effects (Darmancy 1994). Transgenes that confer significant biological advantage may transform wild/weedy plants into new or worse weeds (Rissler and Mellon 1996). The biological process of concern here is introgression (hybridisation among distinct plant species), a major problem in biodiverse farming systems within centres of origin where the possibilities of a transgenic variety encounter with sexually compatible wild relatives is very high. Evidence indicates that such genetic exchanges among wild, weed and crop plants already occur.

The fact that interspecific hybridisation and introgression are common to species such as sunflower, maize, sorghum, oilseed rape, rice, wheat, and potatoes, provides a basis for expecting gene flow between transgenic crops and wild relatives to create new herbicide resistant weeds (Lutman 1999). Transgenic crops can also allow transgenes to escape into free-living populations of landraces. The invasion of transgenes into native varieties could provoke a host of negative effects such as shrinking the agricultural gene pool; clearly any threat to local varieties represents a threat to the food security of local farmers (Snow and Moran 1997).

Environmental risks of insect resistant crops (Bt crops)

Resistance

According to the biotechnology industry, the promise of transgenic crops inserted with Bt genes is that they will replace synthetic insecticides now used to control insect pests. Most crops have a diversity of insect pests, and therefore insecticides will still have to be applied to control non-Lepidoptera pests, which are not susceptible to the Bt toxin expressed by the crop (Gould 1994). But biotechnology has a limited role in pest management, even for Lepidoptera. In the USA the economic advantages of growing transgenic corn are not assured because population densities of the European corn borer are unpredictable.

On the other hand, several Lepidoptera species have been reported developing resistance to Bt toxin in both field and laboratory tests, suggesting that major resistance problems are likely to develop in Bt crops which through the continuous expression of the toxin create a strong selection pressure (Tabashnik 1994). No serious entomologist questions whether resistance will develop or not. The question is how fast?

In order to delay the inevitable development of insects resistant to Bt crops, bioengineers are preparing resistance management plans, using patchworks of transgenics and non-transgenics (called refuges) to delay the evolution of resistance by providing susceptible insects for mating with resistant insects. Although refuges should cover at least 30 per cent of the crop area, Monsanto's new plan calls for only 20 per cent refuges, even when insecticides are to be used. Moreover, the plan offers no details whether the refuges must be planted alongside the transgenic crops, or at some distance away, where studies suggest they would be less effective (Mallet and Porter 1992). In addition to refuges requiring the difficult goal of regional co-ordination between farmers, it is unrealistic to expect most small and medium sized farmers to devote up to 30-40 per cent of their crop area to refuges, especially if crops in these areas are to sustain heavy pest damage.

The farmers who face the greatest risk from the development of insect resistance to Bt are neighbouring organic farmers who grow corn and soybeans without agrochemicals. Once resistance appears in insect populations, organic farmers will not be able to use Bt in its microbial insecticide form to control Lepidoptera pests moving in from adjacent neighbouring transgenic fields; thus losing a valuable biorational tool for pest control.

Effects on non-target species

By keeping pest populations at extremely low levels, Bt crops could potentially starve natural enemies, as predators and parasitic wasps that feed on pests need a small amount of prey to survive in the agroecosystem. Among the natural enemies that live exclusively on insects which the transgenic crops are designed to kill (Lepidoptera), egg and larval parasitoids would be most affected because they are totally dependent on live hosts for development and survival, whereas some predators could theoretically thrive on dead or dying prey (Schuler et al. 1999).

Natural enemies could also be affected directly through inter-trophic level effects of the toxin. The potential of Bt toxins moving through arthropod food chains poses serious implications for natural biocontrol in agricultural fields. Recent evidence shows that the Bt toxin can affect beneficial insect predators that feed on insect pests present on Bt crops (Hilbeck et al.. 1999). Studies in Switzerland show that mean total mortality of predacious lacewing larvae (Chrysopidae) raised on Bt-fed prey was 62 per cent compared to 37 per cent when raised on Bt-free prey. These Bt-prey fed to Chrysopidae also exhibited prolonged development time throughout their immature life stage (Hilbeck et al.. 1999).

These findings are of concern to small farmers who rely for insect pest control on the rich complex of predators and parasites associated with their mixed cropping systems (Altieri 1994). Inter-trophic level effects of the Bt toxin raise serious concerns about the potential of the disruption of natural pest control. Polyphagous predators that move within and between mixed crops cultivars, will encounter Bt-containing non-target prey throughout the crop season (Hilbeck et al.. 1999). Disrupted biocontrol mechanisms may result in increased crop losses due to pests, or to the increased use of pesticides by farmers, with consequent health and environmental hazards.

It is also now known that windblown pollen from Bt crops found on natural vegetation surrounding transgenic fields can kill non-target insects. A Cornell study (Losey et al.. 1999) showed that corn pollen containing Bt toxin can drift several metres downwind and deposit itself on milkweed foliage with potentially deleterious effects on Monarch butterfly populations. These findings open a whole new dimension on the unexpected impacts of transgenic crops on non-target organisms which play key roles in the ecosystem, such as providing alternative food for natural enemies that depend on field margins for their continual existence in agroecosystems (Altieri 1994). But environmental effects are not limited to the interface of crops and insects. Bt toxins can be incorporated into the soil through leaf materials when farmers incorporate transgenic crop residues after harvest. Toxins may persist for 2-3 months, resisting degradation by binding to clay and humic acid soil particles while maintaining toxin activity (Palm et al.. 1996). Such active Bt toxins that end up and accumulate in the soil and water from transgenic leaf litter may have negative impacts on soil and aquatic invertebrates and nutrient cycling processes (Donnegan and Seidler 1999).

The fact that Bt retains its insecticidal properties, and is protected against microbial degradation by being bound to soil particles and persisting in various soils for at least 234 days, is of serious concern for poor farmers who cannot purchase expensive chemical fertilisers. These farmers instead rely on local residues, organic matter, and soil micro-organisms for soil fertility (key invertebrate, fungal, or bacterial species), which can be negatively affected by the soil-bound toxin (Saxena et al.. 1999).

More sustainable alternatives to biotechnology do exist

What is agroecology?

A growing number of farmers, NGOs, and sustainable agriculture advocates propose that instead of the biotechnology capital- and input-intensive approach, developing countries should favour an agroecological model that emphasises biodiversity, nutrient recycling, synergy among crops, animals, soils, and other biological components, as well as regeneration and conservation of resources (Altieri 1996).

Agroecological approaches rely on indigenous farming knowledge, and selected low-input modern technologies, to diversify production. The approach incorporates biological principles and local resources into the management of farming systems, thus providing for an environmentally sound and affordable way for smallholders to intensify production in marginal areas (Altieri et al. 2000b).

There are proven agroecological alternatives to biotechnology that result in technologies that are cheap, accessible, risk averting, productive in marginal environments, environment and health enhancing, and culturally and socially acceptable. A recent analysis of 208 agroecologically based projects and/or initiatives documented clear increases in food production over some 29 million hectares, with nearly 9 million households benefiting from increased food diversity and security. Promoted sustainable agriculture practices led to 50-100 per cent increases in per hectare food production (about 1.71 tonnes per year per household) in rain-fed areas, typical of small farmers living in marginal environments; that is an area of about 3.58 million hectares, cultivated by about 4.42 million farmers (Pretty and Hine 2000). Such yield enhancements are a true breakthrough for achieving food security among resource-poor farmers isolated from mainstream agricultural institutions (Uphoff and Altieri 1999). Some of the examples considered in this study include (Pretty 1995):

Brazil: 200,000 farmers using green manures/cover crops doubled maize and wheat yields;

Guatemala-Honduras: 45,000 farmers using the legume Mucuna as a cover for soil conservation systems tripled maize yields in hillsides;

Mexico: 100,000 small organic coffee producers increased production by half;

South-east Asia: 100,000 small rice farmers involved in IPM farmers' schools substantially increased yields while eliminating pesticides;

Kenya: 200,000 farmers using legume-based agroforestry and organic inputs doubled maize yields.

These examples are but a small sample of the thousands of successful experiences of sustainable agriculture implemented at the local level. Data show that over time agroecological systems exhibit more stable levels of total production per unit area than high-input systems; produce economically favourable rates of return; provide a return to labour and other inputs sufficient for a livelihood acceptable to small farmers and their families; and ensure soil protection and conservation and enhance agrobiodiversity. More importantly, these experiences, which emphasise farmer-to-farmer research and grassroots extension approaches, represent countless demonstrations of talent, creativity, and scientific capability in rural communities. They point to the fact that human resource development is the cornerstone of any strategy aimed at increasing options for rural people and especially resource-poor farmers.

Conclusions

The ecological effects of engineered crops are not limited to pest resistance and creation of new weeds or virus strains. Transgenic crops can produce environmental toxins that move through the food chain, and also may end up in the soil and water affecting invertebrates and probably ecological processes such as nutrient cycling. Gene flow from transgenic crops to landraces can compromise the genetic integrity of centres of origin. Moreover, large-scale landscape homogenisation with transgenic crops will exacerbate the ecological vulnerability already associated with monoculture agriculture (Altieri 2000a). Unquestioned expansion of this technology into developing countries is not desirable. There is strength in the agricultural diversity of many of these countries, and it should not be inhibited or reduced by extensive monoculture, especially when the consequences of doing so results in serious social and environmental problems (Thrupp 1998).

It is through management of this biodiversity that small farmers located in marginal environments in the developing world can produce much of the needed food. The evidence is conclusive: new approaches and technologies spearheaded by farmers, local governments, and NGOs around the world are already making a sufficient contribution to food security at the household, national, and regional levels. A variety of agroecological and participatory approaches in many countries show very positive outcomes, even under adverse conditions. Potentials include: raising cereal yields from 50 to 200 per cent, increasing stability of production through diversification and soil/water management, improving diets and income with appropriate support and spread of these approaches, and contributing to national food security and to exports (Uphoff and Altieri 1999).

Whether the potential and spread of these thousands of local agroecological innovations is realised depends on investments, policies, and attitude changes on the part of researchers and policy makers. Major changes must be made in policies, institutions, and research and development to make sure that agroecological alternatives are adopted, made equitably and broadly accessible, and multiplied so that their full benefit for sustainable food security can be realised. Existing subsidies and policy incentives for conventional chemical approaches must be dismantled. Corporate control over the food system must also be challenged. It is urgent that governments and international public organisations encourage and support effective partnerships between NGOs, local universities, and farmer organisations in order to assist and empower poor farmers to achieve food security, income generation, and natural resource conservation.

Equitable market opportunities must also be developed emphasising fair trade and other mechanisms that link farmers and consumers more directly. The ultimate challenge is to increase investment and research in agroecology and scale up projects that have already proven successful to thousands of other farmers. If such initiatives are complemented with true land reform this holds the promise of productivity gains far outweighing the potential of agricultural biotechnology. While industry proponents will often forecast 15, 20, or even 30 per cent yield gains from biotechnology, smaller farms today produce from 200-1,000 per cent more per unit area than larger farms, world-wide (Rosset 1999). Land reforms that bring average land holdings down to their optimum (small) size from the inefficient, unproductive overly large units that characterise much of world agriculture today, could provide the basis for production increases beside which the much ballyhooed promise of biotechnology would pale in comparison. This will generate a meaningful impact on the income, food security, and environmental well-being of the world's population, especially of the millions of poor farmers yet untouched by modern agricultural technology.

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