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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States 1 Introduction Historians often link the advent of human civilizations with the transition of human societies from food collection primarily through hunting and gathering to food production in established agricultural systems. In a pattern of parallel development, early agricultural systems began emerging in separate regions during the Neolithic period some 10,000 years ago (Mazoyer and Roudart, 2006). Crop-improvement practices based on identification and selection of the best plant varieties appear to date back to the early days of agriculture itself. Similarly, early pastoralists engaged in selective animal breeding. That those practices were recognized as important in the development of ancient human civilizations is apparent in the preservation of instructions on plant breeding in writing, such as in the works of Virgil and Theopastus (Vavilov, 1951). In the broadest sense, the term biotechnology can encompass a wide array of procedures used to modify organisms according to human needs. It can be argued that early agriculturalists engaged in a simple form of biotechnology (Kloppenburg, 2004) in developing the intention and the techniques to improve plant varieties and animal species. Although the process of plant and animal improvement has been continuous throughout the history of agriculture, some historical periods can be identified as singularly transformative. For example, a major agricultural revolution took place in Europe from the 16th to the 19th centuries. It was characterized in part by the extensive use of plants and animals that had been imported from the Americas (Crosby, 2003) and by animal-drawn cultivation and the use of fertilizers, the latter permitting
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States cereal and feed-grain cultivation without fallowing (Mazoyer and Roudart, 2006). That revolution led to important increases in the food supply and thus ultimately permitted increased population growth. Another important change in agriculture resulted from the application of an increasingly scientific approach to plant breeding, which developed from the recognition of the cell as the primary unit of all living organisms in the 1830s (Vasil, 2008) and the work of Mendel (Kloppenburg, 2004). With the rediscovery of Mendel’s principles of genetics in the early 1900s, progress in plant and animal breeding was accelerated. The continuous growth in crop yields and agricultural productivity during the 20th century owes much to those biological discoveries and to a series of mechanical and chemical innovations driven by agricultural research and development. One of the more significant innovations in plant breeding during the 20th century was the development of hybrid crops, particularly corn, in the United States. Hybrid corn varieties, which are developed from crossing different inbred lines, out-yield pure inbred lines, though the seeds produced by hybrid varieties yield poorly. When corn hybrids were first developed, they had no discernible yield advantage over the existing open-pollinated corn varieties of the time (Lewontin, 1990). However, seed companies were motivated to develop high-yielding hybrid varieties; saving and planting the seeds of hybrid corn did not produce equal yields, so seed companies had a financial incentive to invest in these varieties. The research and development efforts devoted to hybrid corn produced tremendous yield improvements over the last 70 years. It is unclear if the same amount of investment could have resulted in similar yield increases for open-pollinated varieties; regardless, because of their limited potential for return on financial investment, efforts to develop high-yielding open-pollinated varieties were not made. Modern hybrids, which have been bred to allocate more of their energy to producing grain rather than stover (leaves and stalks), also demonstrate an ability to maintain high grain production in densely planted fields (Liu and Tollenaar, 2009), and they can exhibit increased tolerance to environmental stresses (such as drought, cold, and light availability). Plant breeders in the 20th century also identified varieties of wheat and rice with shorter stalks and larger seed heads. They were crossed with relatives to create semidwarf wheat and rice varieties, which produced greater yields in part because they responded well to applications of nitrogen and did not lodge despite having heavier seed heads. The development of semidwarf wheat and rice spurred the Green Revolution of the 1960s and 1970s in developing countries (Conway, 1998). Such improvements in plant breeding increased global crop yields in rice and wheat substantially in countries with suitable growing conditions and markets.
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States Recent developments in scientific plant breeding have resulted from discoveries in molecular and cellular biology in the second half of the 20th century that laid the foundation for the development of genetically engineered plants. In 1973, the American biochemists Stanley Cohen and Herbert Boyer were among the first scientists to transfer a gene between unrelated organisms successfully. They cut DNA from an organism into fragments, rejoined a subset of those fragments, and added the rejoined subset to bacteria to reproduce. The replicated DNA fragments were then spliced into the genome of a cell from a different species, and this created a transgenic organism, that is, an organism with genes from more than one species. Before the advent of genetic engineering, plant tissue-culture technology expanded the array of available genetic material beyond what was possible with traditional plant breeding by manipulating the fertilization and embryos of crosses between more distantly related species (Brown and Thorpe, 1995). DNA-recombination techniques opened the possibility of augmenting plant genomes with desirable traits from other species and thus took the science of plant breeding to a stage in which improvement is constrained not by the limits of genetic traits within a particular species but rather by the limits of discovery of genes and their transfer from one species to another to confer desired characteristics on a particular crop. COMMITTEE CHARGE AND APPROACH The committee’s study was the first comprehensive assessment of the impacts of the use of genetically engineered (GE) crops on farm sustainability in the United States. The most up-to-date, available scientific evidence from all regions was used to assemble a national picture that would reflect important variations among regions. Box 1-1 presents the formal statement of task assigned to the committee. In conducting its task, the committee interpreted the term sustainability to apply to the environmental, economic, and social impacts of genetic-engineering technology at the farm level. That interpretation is in line with the federal government’s definition of sustainable agriculture, which is “an integrated system of plant and animal production practices having a site-specific application that will over the long term: Satisfy human food and fiber needs. Enhance environmental quality and the natural resource base upon which the agriculture economy depends. Make the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls.
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States BOX 1-1 Statement of Task An NRC committee will study the farm-level impacts of biotechnology, including the economics of adopting genetically engineered crops, changes in producer decision making and agronomic practices, and farm sustainability. The study will: review and analyze the published literature on the impact of GE crops on the productivity and economics of farms in the United States; examine evidence for changes in agronomic practices and inputs, such as pesticide and herbicide use and soil and water management regimes; evaluate producer decision making with regard to the adoption of GE crops. In a consensus report, the committee will present the findings of its study and identify future applications of plant and animal biotechnology that are likely to affect agricultural producers’ decision making in the future. Sustain the economic viability of farm operations. Enhance the quality of life for farmers and society as a whole.” (Food, Agriculture, Conservation, and Trade Act of 1990) This definition conceives of sustainable farming systems that address salient environmental, economic, and social aspects and their interrelationships. The report explores how GE crops contribute to achieving several of the conditions enumerated above. Farmers must continually adapt in response to environmental, economic, and social conditions by learning and adopting new practices. Adopting GE crops is one option some farmers make in adapting to changing conditions. Though the three aspects of sustainability often interact with one another, the report organizes each in a separate chapter to facilitate access to the information. The chapter on production economics follows the environmental chapter because many of the economic gains and losses that farmers experience with GE crops result from changes occurring within the farm environment from GE-crop adoption. The chapter on social effects is brief because of a lack of published literature on the
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States subject. Nevertheless, the committee deemed this aspect important to include for two reasons. First, social impacts are widely considered to be a necessary element in the definition of sustainability as noted earlier. Second, with the sizable shift in cropping practices and systems to genetic-engineering technology (and the prospect of more GE crops to come), the marked expansion of private-sector control of intellectual property related to seeds, and a growing concentration of private-sector seed companies, it is the committee’s estimation that GE crops have had and will continue to have social repercussions at the farm and community levels. The committee agreed that the report should draw attention to the need for research in this area. In this vein, the report highlights issues on which insufficient information is available for drawing firm conclusions. The final chapter summarizes the main findings of the assessment and discusses the potential for future GE crops to address emergent food, energy, and environmental challenges. The committee interpreted the statement of task to be retrospective in nature, examining the sustainability effects of GE crops on U.S. farms since their commercialization. For that reason the committee focused in large part on the experiences of soybean, corn, and cotton producers because GE varieties of those crops have been widely adopted by farmers, those crops are planted on almost half of U.S. cropland, and most research on genetic-engineering technology in agriculture has targeted those three crops. However, the committee recognized that most farmers have been affected by the widespread adoption of GE crops, even if they have chosen not to adopt them or have not had the option to adopt them. The report examined the effects of genetic-engineering technology on those producers as well. Because the study was retrospective and focused on the experience of U.S. farmers, the adoption of GE crops in other countries entered into the analysis only if U.S. farmers have experienced effects of such adoption, and the committee restricted its speculations on the future applications and implications of genetic-engineering technology to the final chapter. The National Research Council supported the study to expand its contributions to the understanding of agricultural biotechnology. Committee members were chosen because of their academic research and experience on the topic. Experts were selected from the fields of weed science, agricultural economics, ecology, rural sociology, environmental economics, entomology, and crop science. To prepare its report, the committee reviewed previous studies and scientific literature on farmers’ adoption of genetic-engineering technology, the impacts of such technology on non-GE farmers, and environmental impacts of GE crops. It also examined historical and current statistical data on the adoption of GE crops in the United States. The committee acknowledges that GE crops in
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States U.S. agriculture continue to stir controversy around scientific issues and ideological viewpoints. With this in mind, the committee kept its focus on scientific questions and adopted an evidentiary standard of using peer-reviewed literature upon which to base its conclusions and recommendations. It refrained from analyzing ideological positions, either in support of or against the technology, in order to remain as impartial as possible. STUDY FRAMEWORK An analysis of the farm-level sustainability impacts of GE crops requires a framework that integrates all salient factors that motivate their use. We use the principal theories applied to agricultural technology adoption to construct a framework that identifies the qualitative factors that affect U.S. farmers’ decisions to use genetic-engineering technology. With an understanding of the adoption and use processes, we then outline an evaluation framework that spans environmental, economic, and social dimensions as noted above. Two main theories help in building a framework for analyzing a farmer’s decision to adopt a particular GE crop. First, “diffusion” theory seeks to explain people’s propensities to adopt innovations as communicated through particular channels and within particular social systems (Rogers, 2003). Second, “threshold” theory delves deeper into the economic influences on farmer decisions by considering the heterogeneity in farm sizes, in agronomic conditions (climate, soil, water availability, and pest pressure), in forms of human capital that influence learning by doing and using, and in operator values (Feder et al., 1985; Foster and Rosenzweig, 1995; Fischer et al., 1996; Marra et al., 2001; Sunding and Zilberman, 2001). Incorporating those factors allows a better qualitative understanding of the dynamics of the spread of the technologies across the landscape and of their impacts. Together, the diffusion and threshold theories point to five sets of factors that exert influences on a farmer’s decision to use genetic-engineering technology: Productivity (yield) effects. Market structure and price effects. Production-input effects. Human capital and personal values. Information and social networks. Productivity Effects Genetic-engineering technology can directly and indirectly affect crop yields, either positively or negatively, as explained in Chapter 3 in more
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States detail. The direct route stems from the effect on a cultivar after the insertion of one or more traits through genetic engineering. The indirect effect is related to the ability of a GE crop to decrease pest damage (Lichtenberg and Zilberman, 1986a). Just as natural-resource conditions, including pest pressures, vary among fields, farms, and regions, so will the indirect effects on yield and the rate of adoption of GE crops. The technologies tend to be adopted in locations whose agrophysical conditions—such as land quality, climate, and vulnerability to pests—lead to productivity gains (Marra et al., 2003; Zilberman et al., 2003). In addition to effects on quantity, genetic engineering may affect the quality of a crop, which influences its value. Market-Structure and Price Effects Farmers who are deciding whether to grow GE crops must consider their access to domestic and foreign markets. Differential access may stem from country regulations on the entry of GE crops into their markets or from lack of market infrastructure (for example, segmentation of GE and non-GE product chains). Farmers who choose to grow GE crops may experience higher or lower prices than if they grow non-GE crops. For example, if enough farmers adopt a GE crop and yields increase substantially because of direct or indirect effects, crop prices may be forced down by increased supplies, other characteristics remaining the same. Consumers of GE crops may benefit from the lower prices, though some consumers may be willing to pay more for non-GE crops for personal reasons, and this may create a premium for non-GE crops. Under other circumstances, global demand increases may absorb most or all of the increase in supply, in which case prices would not decline (see Chapter 3). Market access and price effects alter farmers’ revenues and profit-ability and thus their disposition to adopt GE crops. The organizational hierarchy of the commodity chain and the nature of farm policies can create structural conditions that act as impediments to or inducers of adoption of a technology (Mouzelis, 1976; Bonanno, 1991; Friedland, 2002; Kloppenburg, 2004). For example, the development of crops with more than one GE trait may create a structural condition for some farmers whereby they may have to pay for traits that they do not need in order to gain access to the traits that they desire (see Chapter 4). Production-Input Effects The adoption and use of GE crops can precipitate changes in the types, amounts, and timing of pesticide use and in the types, frequency,
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States and timing of tillage operations; both can affect machinery requirements. Those changes are referred to as substitution effects; an example is the replacement of some pesticides with a GE crop (Lichtenberg and Zilberman, 1986b). A shift in labor requirements is another potentially important production-input effect (Fernandez-Cornejo and Just, 2007). The availability and quality of GE and non-GE seeds may affect a farmer’s decision to use either. For example, the commercial success of the application of GE soybean and corn in the 1990s was accompanied by increased consolidation and vertical integration in the seed industry (Fernandez-Cornejo, 2004). Indeed, by 1997, two firms captured 56 percent of the U.S. corn-seed market, and this share has increased even more in recent years (see “Interaction of the Structure of the Seed Industry and Farmer Decisions” in Chapter 4) (Boyd, 2003). The changes in genetic-engineering technology and seed-industry structure may help to explain anecdotal statements about the reduced availability of some non-GE seed varieties in recent years (Hill, personal communication). However, the committee is not aware of any published research confirming the link between seed-industry structure and seed availability. Human Capital and Personal Values Every major study of agricultural-technology adoption has found that at least some aspects of human capital play a role in the process. Frequently, the more education or experience a farmer has, the more likely he or she is to adopt a new technology. Educational achievement and years of experience in farming are thought to be proxies for a potential adopter’s ability to learn quickly how to adapt the new technology to the farm operation and to use it to its greatest advantage. As noted above, the process of learning and adaptation is critical to the development of more sustainable farming systems. Farmers also may hold personal values that affect their decisions to use GE crops beyond the financial effects that may flow from productivity, value, and production input. A person’s values define preferences and have been shown to influence decisions on genetic-engineering development and applications (Piggott and Marra, 2008; Buccola et al., 2009). Examples of personal values include aversion to general and specific risks, preference for environmental stewardship, and ideological positions about agricultural systems. An example of the influence of risk aversion is some farmers’ preference for GE crops if they reduce the variability of yields because they improve control of pests. Such risk reduction can motivate adoption of GE varieties by risk-averse farmers and may also lead to an increase in use of complementary practices, such as no-till planting (Alston et al., 2002; Piggott and Marra, 2007).
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States Information and Social Networks Decisions of whether to adopt GE crops hinge on the quantity and quality of farmers’ information about the characteristics and performance of the technologies. Information from formal sources, such as the agricultural media, on GE traits’ technical aspects, economic implications, and prospects can shape farmers’ views. Informal sources probably also speed or slow the adoption of GE crops (Wolf et al., 2001; Just et al., 2002). Social networks can have favorable or unfavorable effects not only on the adoption of technologies but also on the sharing of knowledge about GE and non-GE crops and on the development of new technologies and management strategies (Arce and Marsden, 1993; Busch and Juska, 1997; Hubbell et al., 2000). They can also mitigate potentially negative social impacts of GE-crop adoption. Recognition of the importance of social networks has been enhanced by studies of the processes associated with the use of alternative agricultural practices (Storstad and Bjørkhaug, 2003; Morgan et al., 2006). Insights derived from the study of social networks also may have great relevance to the development and dispersion of genetic-engineering technology. Figure 1-1 portrays the influences of the different factors on GE-crop adoption decisions and the resultant impacts on environmental, economic, and social conditions. This conceptual model shows that factors under the control of the farmer, such as human capital, and outside their control, such as market prices, come together to influence the GE-crop adoption decision process, depicted by the central box in the figure. It also shows how the factors, up to this point presented as having distinct effects, may influence each other. Examples of potential interactions include the effects of information and social networks on personal values and production inputs and the effect of production-input substitution on productivity. Other impacts of decisions related to GE crops (for example, the environmental effect of pest population changes) may feed back to some influencing factors, such as production inputs. As discussed later in this chapter, empirical studies have found that factors in each of the categories have influenced GE-crop adoption patterns. However, it is not possible to rank the magnitude of influences in a general sense. Rather, we expect that the different factors will vary in influence across types of farms, geographic regions, and specific crop applications. For example, if a certain pest infestation is severe in a region, then the productivity gains from adopting a GE crop may far outweigh the influence of personal values of the adopter. In another case where pest pressures are moderate compared to those in other regions, functioning information and social networks may influence the speed and rate of adoption of genetic-engineering technology.
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States FIGURE 1-1 Genetically engineered crop adoption and impact framework. GENETICALLY ENGINEERED TRAITS IN CROPS For agricultural crops, the first generation of genetic engineering has targeted traits that increase the efficacy of pest control. Since the introduction of GE crops, new seeds have provided pest control in one or more of three forms: Herbicide resistance. Insect resistance. Virus resistance.
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States The terms resistance and tolerance are often used interchangeably in the literature. Tolerance implies that a crop is affected by a pesticide but has a means to naturally survive the potential damage sustained. This report uses the more precise term resistance because altered genes either allow a plant to generate its own insecticide or prevent herbicides from damaging the plant (Roy, 2004). GE herbicide-resistant (HR) crops contain transgenes that enable survival of exposure to particular herbicides. In the United States, crops are available with GE resistance to glufosinate and glyphosate, but most HR crops grown in the United States are resistant only to glyphosate, a nonselective chemical that has a low impact on the environment. Glyphosate inhibits the enzyme 5-enolpyruvyl-shikimate-3-phosphate synthase (EPSPS), which is part of the shikimate pathway in plants. The shikimate pathway helps produce aromatic amino acids; it is speculated that glyphosate kills a plant either by reducing aromatic amino acid production and adversely affecting protein synthesis or by increasing carbon flow to the glyphosate-inhibited shikimate pathway, causing carbon shortages in other pathways (Duke and Powles, 2008). The susceptibility of EPSPS to the chemical and the relative ease with which it is taken up by a plant make glyphosate an extremely effective herbicide. It presents a low threat of toxicity to animals in general because they do not have a shikimate pathway for protein synthesis (Cerdeira and Duke, 2006). Glyphosate also has low soil and water contamination potential because it binds readily to soil particles and has a relatively short half-life in soil (Duke and Powles, 2008). Insect-resistant (IR) plants grown in the United States have genetic material from the soil-dwelling bacterium Bacillus thuringiensis (Bt) incorporated into their genome that provides protection against particular insects. Bt produces a family of endotoxins, some of which are lethal to particular species of moths, flies, and beetles. An insect’s digestive tract activates the ingested toxin, which binds to receptors in the midgut; this leads to the formation of pores, cell lysis, and death. Individual Bt toxins have a narrow taxonomic range of action because their binding to midgut receptors is specific; the toxicity of Bt crops to vertebrates and many non-target arthropods and other invertebrates in U.S. agricultural ecosystems is effectively absent. The first Bt crops that were introduced produced only one kind of Bt toxin. More recent varieties produce two or more Bt toxins; this enhances control of some key pests, allows control of a wider array of insects, and can contribute to delaying the evolution of resistance in target pests while reducing refuge size. Gene sequences of pathogenic viruses have been inserted into crops to confer protection against related viruses—to make them virus-resistant (VR). Most transgenic VR plants resist viruses through gene silencing,
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States Market Conditions Influencing the Commercialization of Genetically Engineered Varieties Most research in and development of GE crops are conducted by private firms. Private companies must produce profits for their shareholders, so the marketability of a crop plays a determining role in decisions as to which GE crops are brought to commercialization. Market size, trait value, regulatory costs, environmental concerns, and technology access influence biotechnology firms’ decisions to develop and sell GE seeds. The market for seeds must be large enough to warrant the investment in commercialization. If markets are too small or are characterized by farmers with low ability to pay for the technology, the benefits to firms are too low to induce them to introduce GE varieties. That is one of the reasons that specialty crops have largely been overlooked in genetic engineering. The VR papaya, for example, was developed through public research. In addition, the number of researchers in these types of crops is considerably smaller and the marketing infrastructure less extensive than for soybean, corn, and cotton. That lack of resources, the diversity of species, the relatively short marketing season, and the small number of planted acres combine to deter private-sector investment in genetic-engineering technology for specialty crops (Bradford and Alston, 2004). To collect sufficient returns, firms instead invest in widely grown crops that have long storage life and that have year-round marketing potential. That generally means that farmers growing such crops have access to genetic-engineering technology, whereas the option is not available to farmers growing specialty crops or crops that are not widely grown in the United States. The cost of regulatory compliance to ensure that GE crops do not pose unacceptable food safety and environmental risks has become an important component of the overall cost of new biotechnologies (Kalaitzandonakes et al., 2007). These costs may have contributed to limiting the development of GE minor crops, as was the case with pesticide development during the 1970–1990 period. As Ollinger and Fernandez-Cornejo (1995) found, “pesticide regulations have encouraged firms to focus their chemical pesticide research on pesticides for larger crop markets and abandon pesticide development for smaller crop markets.” Obtaining regulatory clearance of GE crops in the United States is a long process, and the cost per crop can be very high. Furthermore, for crops with wild, weedy relatives (e.g., wheat), the potential for gene flow raises their environmental risk and expense (see “Gene Flow and Genetically Engineered Crops” in Chapter 2). Large private firms have concluded that investment in less widely grown crops does not generate adequate returns to justify the development and regulatory cost of bringing them to market.
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States Research and development in genetic-engineering technology have been stimulated by the development of patent protection for GE organisms. Changes in intellectual-property rights (IPR) law in the 1970s and 1980s are largely responsible for creating a profitable environment for biotechnology research. However, that protection may also create constraints on the development of GE varieties of more crops. Companies that control the patents may be unwilling to provide licenses or offer licenses at affordable prices to public-sector researchers or other companies that would like to develop seeds for smaller markets. A similar restriction may occur when university scientists patent genetic material that becomes essential for development of GE crops by other university scientists. Thus, the mechanism that generated the incentives to develop and commercialize genetic engineering may limit its applicability to most crops (Alston, 2004). The influence of IPR on the commercialization of genetically engineered crops will be discussed further in Chapter 4. Marketing decisions are also influenced by perceived consumer acceptance of GE products. If technology providers have reason to believe that a GE crop will not be purchased by consumers, the technology will not be commercialized regardless of the potential benefits of the technology to producers. Indeed, a product may even be decommercialized if consumer avoidance, or the fear of it, is high enough. For example, consumer concerns and competing pest-control products caused the GE potato to be discontinued (see Box 1-2). The perceived potential loss of markets has also postponed the commercialization of GE wheat (this is covered further in Chapter 4). Consumers appear to be more accepting of products that are further removed from direct consumption, although additional research is needed in this regard (Tenbült et al., 2008). Thus, companies have been more willing to invest in corn and soybean, which are used primarily for animal feed and processed products, and cotton, a fiber crop. Even though wheat and rice are grains (like corn), are widely planted, and have a considerable storage life, their proximity to the consumer in the food supply chain has contributed to additional pressures on the private sector, which may explain firms’ wariness to introduce genetic-engineering technology into them (Wisner, 2006). Resistance to Genetic-Engineering Technology in Organic Agriculture As outlined above, genetic-engineering technology is not available to farmers of most crops. However, some producers have chosen not to adopt the technology regardless of its accessibility. That attitude is typified by organic production in the United States. As American agricultural practices incorporated greater use of synthetic chemicals in the 1950s and 1960s, organic production gained
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States popularity as an alternative farming system. By the 1980s, the organic movement was large enough to justify the establishment of national certification standards. The proliferation of standards, inconsistency in labeling, difficulty in marketing, and inability to police violators of standards prompted organic groups to push for passage of the Organic Foods Production Act (OFPA) of 1990 (Rowson, 1998). The OFPA authorized a National Organic Program (NOP) in the U.S. Department of Agriculture (USDA) to define organic farming practices and acceptable inputs. The act established an advisory group, the National Organic Standards Board (NOSB), to provide recommendations to USDA on the structure and guidelines of the NOP. The NOSB viewed GE organisms as inconsistent with the principles of organic agriculture and recommended their exclusion (Vos, 2000). Opponents of genetic-engineering technology in organic production raised concerns about food safety and environmental effects. They also argued that organic agriculture is based on a set of values that places a high priority on “naturalness” (Verhoog et al., 2003), a criterion that in their view genetic engineering did not meet. The proposed rule that was issued in 1997 deemed GE seeds permissible in organic agriculture; subsequently, USDA received a record number of public comments, almost entirely in objection to the proposal (Rowson, 1998). In response to the opposition, USDA rewrote the standards. When the NOP final rule went into effect in 2001, GE plants were not considered to be compliant with standards of organic agriculture (Johnson, 2008). FROM ADOPTION TO IMPACT The assessment framework described earlier in this chapter spans all the qualitative dimensions necessary to evaluate the potential sustainability of genetic-engineering technology. Therefore, this report’s structure covers environmental, economic, and social changes, and the following chapters report progress and conclusions in these realms. Environmental Effects The landscape-level environmental effects of GE crops, both potential improvements and risks, did not receive extensive study when such crops were first planted widely (Wolfenbarger and Phifer, 2000; Ervin et al., 2000; Marvier, 2002). Since then, many studies on nontarget effects, including further studies requested by the U.S. Environmental Protection Agency, have accumulated. Other studies and analyses have related adoption of GE crops to changes in pesticide regimens and tillage practices. However, longitudinal data are still needed to better understand the effects of changes in farm management on environmental sustain-
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States ability, such as on water quality or on resistance to glyphosate in weeds. Comprehensive evidence on other environmental dimensions—such as some aspects of soil quality, biodiversity, water quality and quantity, and air-quality effects—is also sparse. The environmental effects of farmers’ adoption of genetic-engineering technology are discussed in Chapter 2. Economic Effects The economic effects of genetic-engineering technology in agriculture, which are addressed in Chapter 3, stem from effects on crop yields; the market returns received for the products; reductions or increases in production inputs and their prices, such as the costs of GE seeds and pesticides; and such other effects as labor savings that permit more off-farm work or that result in changes in yield risk. Those effects have received considerable study, particularly in the early stages of adoption of GE crops. However, recent information is sparse even though new GE varieties continue to be introduced. Less farm-level economic analysis has been conducted, perhaps because of the near dominance of the technologies in soybean, cotton, and corn production, because serious production or environmental problems have not surfaced, and because there is less interest for conducting additional research in a well-studied arena. More extensive studies of some economic effects, such as those on yield, have been conducted more recently in developing countries than in mature markets such as the United States. Social Effects The social effects of the adoption or nonadoption of genetic-engineering technology have not been studied as extensively as those attributed to previous waves of technological development in agriculture, even though earlier studies demonstrated that revolutionary agricultural technologies generally have substantial impacts at the farm or community level (Berardi, 1981; DuPuis and Geisler, 1988; Buttel et al., 1990) and that there was a high expectation that genetic-engineering technology would also have substantive and varied social impacts (Pimentel et al., 1989). It is thus surprising that there has been relatively little research on the ethical and socioeconomic effects of the adoption of agricultural biotechnology at the farm or community level (e.g., Buttel, 2005). A few studies have explored the economic effects of structural changes (integration and concentration) in the seed and agrichemical industries (Hayenga, 1998; Brennan et al., 1999; Fulton and Giannakas, 2001; Fernandez-Cornejo and Schimmelpfennig, 2004; Fernandez-Cornejo and Just, 2007). However, though the issue of how farmers might be socially impacted by the
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The Impact of Genetically Engineered Crops on Farm Sustainability in the United States increasing integration of seed and chemical companies was first raised more than 20 years ago (Hansen et al., 1986), the organizations responsible for conducting or sponsoring research on the effects of genetic-engineering technology have generally fallen short of promoting the comprehensive and rigorous assessment of the possible social and ethical effects of GE-crop adoption. That responsibility rests not only with federal agencies (Kinchy et al., 2008) but with state governments, universities, nongovernment organizations, and the private for-profit sector. The absence of such research reduces our ability to document what the effects of the adoption of genetic-engineering technology have been on farm numbers and structure, community socioeconomic development, and the health and well-being of farm managers, family members, and hired farm laborers. A particularly significant question that has not been adequately assessed is whether the adoption of GE crops has exacerbated, alleviated, or had a neutral effect on the steady decline of farm numbers and the vitality of rural communities often associated with the industrialization of U.S. agricultural production. Because of the comparative dearth of empirical research findings on the social impacts of GE-crop adoption in the United States, we offer in Chapter 4 a discussion of the potential effects of the introduction of genetic-engineering technologies on farming-system dynamics in the form of testable hypotheses and piece together the ancillary literature on documented social effects, such as legal disputes. CONCLUSION Genetic-engineering technology has been built on centuries of plant-breeding experiments, research, and technology development. Commercialized applications have focused on pest management, primarily through resistance to the herbicide glyphosate and the incorporation of endotoxins that are lethal to some insect pests. Those traits have provided farmers of soybean, corn, and cotton with additional tools for combating pests. The popularity of GE crops is evidenced by their widespread adoption by farmers. In the following three chapters, we examine how their adoption has changed or reinforced farming practices and what implications the changes have for environmental, economic, and social sustainability at the farm level. At the close, we identify remaining challenges and opportunities for GE crops in the United States and draw conclusions and recommendations for increasing their contributions to farm sustainability. REFERENCES Alston, J.M. 2004. Horticultural biotechnology faces significant economic and market barriers. California Agriculture 58(2):80–88.
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