Biotechnology and Pest Control

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Biotechnology and Pest Control: Quick Fix vs. Sustainable Control
by Jane Rissler

Biotechnology promoters argue that new biological and genetic approaches to boost agricultural yields will end world hunger and solve problems created by chemically intensive farming. Is this new technology a solution for the problems of agriculture? The answer is not a simple yes or no. Biotechnology could be part of a solution, but thus far it is being pushed in the wrong direction. It is being touted as the successor to chemicals as a miracle technology , a quick fix, rather than an integral part of a shift to sustainable agriculture. One of the best examples of this trajectory in agricultural biotechnology can be seen in current trends in the genetic engineering of organisms to control pests.

Chemical Pesticides: The First Quick Fix

Agricultural chemicals are the backbone of an effort that has produced stunning increases in productivity over the last forty years. The synthetic chemical pesticide industry that emerged from World War II offered farmers what appeared to be miracle chemical compounds to control pests and enhance yield. In their book Integrated Pest Management, Flint and van den Bosch described the subsequent transformation of agriculture:

Their success was immediate. [Chemical pesticides] were cheap, effective in small quantities, easy to apply, and widely toxic. They seemed to be truly "miracle" insecticides. The effect of the new pesticides on the attitude of those who controlled pest organisms was revolutionary. Where farmers had formerly talked of "controlling" pests, expecting to have to tolerate certain levels of the noxious species, they now talked of "eradicating" pests. People envisioned the extermination of entire species of pest insects, plant pathogenic organisms, and weeds and expected 100% kill from their pest control actions.

With such dramatic success, it is easy to understand why the use of pesticides caught on so quickly. Indeed, in the decades after the war, pest control became predominantly a matter of chemistry. Where management of pest problems previously relied on ecological principles, farmers were now encouraged to abandon many preventative pest control measures like rotating crops, simultaneous cropping, and encouraging natural enemies of pests.

Not only farmers were transformed by the chemical revolution. Public agricultural institutions in the United States, including the U.S. Department of Agriculture (USDA), state agricultural institutions, and agricultural universities, shifted their research and education mission from agriculture as a biological and ecological activity to one based on chemicals.

The results are well known. Widespread adoption of chemical pesticides contributed to unprecedented increases in crop yields, but also resulted in the poisoning of farmworkers and rural residents, contamination of food and drinking water, destruction of wildlife habitats, and decimation of wildlife. From the long-term perspective, agricultural chemicals have turned out to be less than miraculous.

Choosing a Path for Biotechnology

Now biotechnology, the new "miracle" technology, is being adapted for use in agriculture. The developers of biotechnology face a spectrum of choices. It could be used to support an agricultural system based on the principles of ecology, stability, and sustainability. Or, at the other end of the spectrum, it can serve as another "quick fix" in conventional, industrial-style agriculture. A look at the major promoters and the first products of the technology shows that the choice, thus far, is well toward the "quick fix," industrial end of the spectrum.

Biotechnology is being shaped within the same social context and value system that led to chemical dependence. The same institutions that developed and promoted chemical-style farming, agrochemical giants such as Monsanto, DuPont, and Ciba-Geigy, and the USDA, are now proclaiming biotechnol- ogy as the route to sustaining high yields, while reducing our dependence on chemicals and the problems created by that dependence. Agrochemical companies are investing millions of dollars in biotechnology research to create genetically engineered plants, animals, and microorganisms to repel pests, make fertilizers, and enhance yield. The USDA, following the lead of agribusiness, is also a major promoter of biotechnology, placing it high among its research priorities and investing millions of taxpayer dollars in research. USDA officials even distribute promotional buttons that read: "Biotechnology the Future of Agriculture." Biotechnology is being developed with the same vision that promoted chemicals to meet the single, short-term goals of enhanced yields and profit margins. This vision embraces a view of the world characterized by beliefs that nature should be dominated, exploited, and forced to yield more; by preferences for simple, quick, immediately profitable "solutions" to complex ecological problems; by "reductionist" thinking that analyzes complex systems like farming in terms of component parts, rather than as an integrated system; and by a conviction that agricultural success means short-term productivity gains, rather than long-term sustainability.

As a clear indicator that agricultural biotechnology is headed in the wrong direction, the first pest-control products (like the chemical pesticides that preceded them) are designed to support conventional, high-input agricultural systems. The first three genetically engineered products, herbicide-tolerant crops, insect-resistant crops and microorganisms, and virus-resistant crops, were all developed for easy adoption within existing industrial-style agriculture.

Herbicide Resistance

Genetically engineered herbicide-tolerant crops are likely to be the first commercially available products. They are deeply embedded in the chemical quick-fix mentality. Herbicide-tolerant crops are engineered to contain new genes that help plants avoid the harmful effects of particular weed killers. Currently, a crop's sensitivity to a weed killer limits the amount of herbicide growers can apply. With herbicide-tolerant crops, farmers can be persuaded to use more of a particular herbicide to kill weeds without damaging their crop.

Herbicide-tolerant crops represent a simple strategy for chemical companies to market more of their herbicides. All eight major transnational pesticide companies, Bayer, Ciba- Geigy, ICI, Rhone-Poulenc, Dow/Elanco, Monsanto, Hoechst, and DuPont, are currently funding research to develop a variety of crops that tolerate their herbicides. Monsanto, for example, has already field-tested genetically engineered glyphosate -tolerant tomato, cotton, soybean, flax, and canola.

Rather than help wean U.S. agriculture from its dependence on toxic chemicals, herbicide-tolerant crops perpetuate and extend the chemical pesticide era and its attendant human health and environmental toll. The effects of the nation's massive herbicide useP600 million pounds applied annuallyPare already alarming. Studies link various weedkillers with cancer, nervous disorders, behavioral changes, and skin diseases in humans and animals. In addition to poisoning farmworkers who handle herbicides, weed killers enter groundwater and other drinking water supplies, contaminate food, and destroy wildlife and their habitats. Not only do herbicide-tolerant crops sustain dependence on harmful chemicals, they also have the potential, in the long run, to exacerbate weed control problems. Widespread use of these crops and their associated herbicides will exert significant pressure on populations of weeds to develop tolerance to the herbicides, thus rendering the herbicides ineffective in controlling the weeds. Already, herbicide- resistant weeds have arisen in areas where certain weed killers are heavily used. The larger amounts of particular herbicides applied in association with herbicide-tolerant crops will only increase the selection pressure for additional resistant weeds.

Furthermore, the transfer of genes for herbicide resistance to weedy relatives could make some weeds more difficult to control in agricultural settings. For example, oilseed crucifers (rapeseed or canola) that have been engineered to resist herbicides, are related to wild mustards that are important weeds in U.S. agriculture. It is virtually certain that herbicide-tolerance genes would be transferred via cross pollination from the engineered crucifers to wild, weedy relatives, resulting in weeds resistant to herbicides and therefore more difficult to control.

Insect Resistance

Reducing crop loss caused by insects is also a major focus of agricultural biotechnology research. Monsanto, Rohm and Haas, Ciba-Geigy, Agracetus, Agrigenetics Advanced Sciences, Calgene, the USDA, and the University of California have developed and field tested tomato, tobacco, cotton, walnut, and potato plants genetically engineered to contain an insect-killing toxin from Bacillus thuringiensis (B.t.). Sandoz Crop Protection and Crop Genetics International are genetically engineering microorganisms containing B.t. toxin to act as biocontrol agents.

B.t. is a soil microorganism that has been used for twenty years as a commercial biocontrol agent against certain insect pests. Knowing that specific toxins were responsible for B.t.'s insecticidal activity, genetic engineers have isolated and removed the genes that produce the toxins, and placed them in plants and microorganisms. Engineers are designing B.t.-containing crops, trees, and microbes to combat an array of insect pests: European corn borer, cotton bollworm, Colorado potato beetle, beet armyworm, tobacco hornworm, and tomato fruitworm.

Despite their promise for reducing the use of chemical insecticides, widespread use of B.t.-containing crops and microbes poses a potentially significant problem: accelerated evolution of pest resistance to B.t.. If this were to happen, agriculture would lose one of its safest, most valuable biocontrol agents.

Already, some insect populations (e.g., diamondback moth) have become resistant to the B.t. toxin after prolonged exposure. Resistance in a particular insect pest population means that B.t. would no longer be effective in controlling that pest. It is generally accepted that the intensive use of B.t. in genetically engineered organisms will accelerate the selection pressure on insect populations to develop resistance. In engineered plants that produce the B.t. toxin throughout the life of the plant, insects will be exposed more frequently and for longer periods. This intensified selection pressure contrasts with conventional methods of delivering B.t. where the toxin is active for only a limited period after application.

Virus Resistance

Viruses cause economically important diseases in most of the major agricultural crops. Thus far, there are no chemical viricides that do not also harm crops. Some crops are treated with insecticides to kill insects that carry viruses from plant to plant.

Plant genetic engineers have suggested a new approach to controlling viruses; they are engineering plants to contain a virus gene. The plant then produces a viral protein which enables the plant to resist attack by the same virus. The result is similar to immunities created by vaccinating people and animals against diseases. Monsanto, Agrigenetics Advanced Sciences, Pioneer Hi-Bred, Upjohn, Cornell University, and the University of Kentucky have field-tested genetically engineered virus-resistant plants including potato, tomato, tobacco, alfalfa, cucumber, cantaloupe, and squash.

Adoption of virus-resistant plants may, in the short term, reduce the use of chemical insecticides and losses due to viruses. For the long term, however, it remains unclear how fast viruses might evolve resistance to virus genes incorporated into resistant plants, rendering those engineered plants once again susceptible to virus attack.

Crops genetically engineered to resist herbicides, insects, and virus diseases, like chemical pesticides, will be sold to farmers as single, simple-to-use products to control pests and sustain continuous monoculture. They are being developed to fit immediately and easily into conventional agriculture's industrialized monoculture, and as such they extend what Jack Doyle has called "the 'invade and conquer' and 'replacement parts'" approach to pest management. This kind of farming entrenches farmers' dependence on successive new products from corporations, new genetically manipulated organisms to serve as quick fixes for increasingly complex pest control problems.

Sustainable Agriculture: A Better Path For Pest Control

There is a better approach to pest control than chemical or genetically engineered products aimed at one or a group of pests: pest management methods developed in the context of sustainable agriculture. Also known as alternative agriculture or low-input sustainable agriculture, these approaches to profitable farming recognize the ecological nature of agriculture and incorporate responsible stewardship of natural resources.

What this means for pest control is that growers (and agronomists) need to change their expectations and methods. In sustainable systems, the goals are prevention and management, unlike the control or eradication objectives of chemical farming. Sustainable management strategies emphasize prevention of pest problems by providing conditions that optimize the effect of natural mortality factors (e.g., biological enemies and weather) to reduce pest populations. They depend heavily on large amounts of ecological, biological, agronomic, and climatic information.

In sustainable systems, farmers use a variety of cultural, biological, and mechanical methods to avoid or reduce pest problems. Crop rotations, intercropping, cover crops, altered planting and tilling schedules, new tillage systems, and natural biocontrol agents are some of the many options available to growers adopting sustainable strategies.

Biotechnology could make contributions to sustainable agricultural systems, but those contributions would have more to do with enhanced understanding and manipulation of crop/pest/environment interactions than with producing specific engineered plants or microbes for the marketplace. For example, modern molecular biology and genetic techniques, in concert with ecological studies, could be used to dissect the relationship between soybean seedlings and the charcoal rot fungus as it is influenced by environmental factors. Under certain environmental conditions in the tropics, charcoal rot can decimate young soybean plants. If the molecular and biochemical steps in disease development were characterized, scientists could determine not only which steps are susceptible to control measures, but what measures would be successful in interrupting disease development. They could develop specific, targeted strategies to block critical interactions and prevent seedling rot. These strategies might employ natural disease suppressive agents in crops interplanted or rotated with soybeans, incorporate specific genes for rot resistance, enhance soybean's natural defense mechanisms, or involve altered cultural conditions and planting dates.

Sustainable agriculture provides an appropriate context for developing biotechnology. Pest control is only one area in which biotechnology is on the wrong path. Biotechnology development in general is headed in the wrong direction. In a recent critique of modern agriculture, Angus Wright comments on the path taken by agricultural biotechnology:
[Biotechnology promoters] want to remove agricultural research and the reproduction of crops even farther from the wisdom of practicing farmers and the slow process of adaptation through natural and cultural evolution. We need instead to move in the opposite direction, toward the readaptation of agriculture to the complexity of nature and the requirements of healthy human beings and healthy human communities.

Genetic engineering techniques could prove useful for analyzing and understanding the complex and interwoven ecological and biological processes that make agriculture possible. Yet its proponents circumscribe its potential by using it to design products that extend a nonsustainable, nonecological agricultural system.

The development of biotechnology should be shaped within the context of sustainable agricultural systems, ecologically based systems that reflect the goals of long-term economic viability, productivity, and natural resource stability. Rather than invest taxpayer dollars in biotechnology research that supports conventional agriculture, publicly funded agricultural research must be directed toward sustainable approaches.

We should reject high-input, industrial-style monoculture; avoid quick-fix, short-term solutions; and adopt ecologically based, sustainable farming systems. Biotechnology techniques should only be used within ecological research to search for innovative and sustainable solutions to agriculture's economic, social, and environmental problems.

Jane Rissler is Biotechnology Specialist at the National Wildlife Federation, 1400 16th Street N.W., Washington, D.C., USA.

For further reading:

Jack Doyle, "Sustainable agriculture and the other kind of biotechnology," In Reform and Innovation of Science and Education: Planning for the 1990 Farm Bill, Committee on Agriculture, Nutrition, and Forestry, U.S. Senate, 101st Congress, 1st Session, December 1989.

M.L. Flint and R. van den Bosch, Integrated Pest Management, Plenum Press, NY, 1981.

Rebecca Goldburg, Jane Rissler, Hope Shand, and Chuck Hassebrook. "Biotechnology's Bitter Harvest: Herbicide- Tolerant Crops and the Threat to Sustainable Agriculture," Biotechnology Working Group, 1990.

Wes Jackson, "Biotechnology and supply side thinking." The Land Stewardship Letter, Vol. 5, No. 2, pp. 10-12, spring 1987..

National Research Council, Alternative Agriculture, National Academy Press, Washington, DC, 1989.

Angus Wright, The Death of Ramon Gonzalez: the Modern Agricultural Dilemma, Univ. of Texas Press, Austin, 1990.

John Young, "Bred for the hungry?" World Watch, Vol. 3, No. 1, pp. 14-22, January/February 1990.