California
Cotton Ginners and Growers Association Annual Meeting
and
UC
Cooperative Extension Winter Cotton Production Meeting
Visalia
Convention Center
February
16, 2000
Agricultural Biotechnology
Kent
J. Bradford, director, Seed Biotechnology Center
University
of California
Davis,
CA 95616
kjbradford@ucdavis.edu
Let me first express my appreciation to Earl Williams and the organizers
of this meeting for inviting me to speak to you. While my specific scientific
expertise is not in cotton, I was raised on a cotton farm in the Texas Panhandle
and my mother and brothers currently operate a farming and cotton ginning
enterprise south of Amarillo. I have therefore followed developments in the
cotton industry with considerable interest, and appreciate the opportunity to be
here today to learn more.
This is an important time for the California cotton industry, with many changes, challenges, and opportunities happening simultaneously. One of these is the large-scale introduction of cotton varieties that have been genetically enhanced to provide specific production benefits. For a number of reasons, the introduction of varieties developed using biotechnology has been slower in California than in the rest of the country, where more than 50% of the acreage of some crops already utilizes herbicide and insect tolerant varieties. Last year about 70-80,000 acres of cotton were grown in California that contained traits enhanced by biotechnology, and the acreage of such varieties is likely to increase this year. Part of my job as Director of the UC Davis Seed Biotechnology Center is to participate in educational opportunities to talk about biotechnology and its applications in agriculture. The Seed Biotechnology Center at UC Davis is a program of the College of Agricultural and Environmental Sciences, in partnership with the seed and plant biotechnology industries, to facilitate discovery and commercialization of new germplasm and seed technologies for agricultural and consumer benefit. Certainly I do not presume to be able to educate this audience about agriculture or cotton production, and the UC Cooperative Extension program that follows will be extremely valuable for specific information about cotton varieties and production methods. What I would like to do instead is give a broader background about agricultural biotechnology and discuss some of the controversial issues that we will be facing during the coming year.
First, what is agricultural biotechnology? Biotechnology has been defined broadly as a wide range of technologies that involve the manipulation of living organisms or their components to provide useful products, processes or services. In the broadest sense, biotechnology includes things like making bread or beer, where a living organism (yeast) is used in the production process. Similarly, one could easily define agriculture as the manipulation of living organisms or their components to provide useful products, processes or services. In a very real sense, agriculture is the original biotechnology, which began when humans purposefully manipulated the plants and animals in their environment to improve their productivity and utility. Archeologists have determined that the purposeful cultivation of crops was established in at least some places in the world by 10,000 years ago, and was being practiced on all continents (except Australia) by about 5000 years ago. During this time most of our important crops were domesticated, including wheat, rice, corn, beans, squashes, and numerous others. The process of domestication means that genetic changes occurred that improved the crops for human purposes. For example, in crops where the seed is the food product, seed size increased dramatically under human selection, and instead of being shed from the plant at maturity, the seeds were retained on the plant until harvest. These changes were all the result of genetic changes in the crop plants resulting from variation present in the wild parents followed by (largely inadvertent) selection by early agriculturists.
Not until the rediscovery of Mendel’s work in the early 1900’s did the science of genetics enter into the process of genetically improving crop plants. Mendel demonstrated that the specific characteristics of plants (peas in his case) are transmitted between generations as discrete units (called genes) and that their appearance in subsequent generations follows certain statistical probabilities. This led to targeted breeding efforts to select for more desirable combinations of genes that would result in higher crop yield or quality. If there is sufficient variation in the parental lines, this can be an effective method of crop improvement. For example, corn yields could be increased 50% after only 14 generations of selection, and cotton lint yield potential doubled between 1910 and 1980 due to genetic improvement. In addition to selecting among natural variation, breeders have also attempted to increase genetic variation by methods such as irradiation, which introduces novel mutations, some of which may be beneficial. Additional traits can also be introduced from related varieties or species that can be sexually crossed with the target variety. This process is called “introgression,” and has allowed important improvements to be made in many crops. As an example important in California, the entire tomato industry is dependent upon disease resistances, nematode resistance, and fruit quality traits that have been introduced into cultivated varieties from related wild species. The 60-year career of Dr. C.M. Rick at UC Davis and his collections of wild tomato accessions from the South American Andes have been critical to overcoming production constraints that would have severely handicapped tomato production in California. Similar examples can be cited from virtually all cultivated crops, and each of these improvements involved the incorporation of genetic material from wild species into the cultivated variety.
In the 1920’s and 1930’s, it was discovered that additional gains in yield could be achieved by making specific crosses between inbred parent lines. Repeated inbreeding or self-pollination results in reduced vigor in many species, but when two distinct inbred parents are crossed, the resulting offspring (called the F1 generation) exhibits a large increase in growth known as hybrid vigor or heterosis. Because it was relatively easy to make specific crosses in corn, and it exhibits a strong heterosis response, hybrid varieties have been used almost exclusively in the corn industry for the past 50 years. While hybrids utilize normal crossing techniques, they involve specific manipulation of the genetic composition of the plant to achieve desired results.
No doubt most of you are quite familiar with this history of crop genetic improvement, which is responsible 60% of the yield increases that have been recorded over the past century (improvement in fertilization, irrigation and management contributing the remaining 40%). It is important to keep this history in mind, however, in connection with the current discussion about “genetically modified organisms,” or GMOs. This term has been applied recently to the modern products of biotechnology, but it is evident that this term is a misnomer, as ALL of our cultivated crop plants have been extensively modified genetically, first and most dramatically by domestication, and subsequently by targeted selection and breeding methods. The term GMO itself is misleading, as it implies that only the products of modern biotechnology are genetically modified, and the term has been used specifically by some groups to create a negative image of biotech products. For these reasons, many groups supporting the use of biotechnology in agriculture recommend that this term not be used to describe the products of agricultural biotechnology.
While genetic improvement of crops is as old as agriculture itself, the development of recombinant DNA techniques has dramatically expanded our ability to transfer traits among different organisms. In the early 1970’s, enzymes were discovered that could cut DNA molecules in specific locations and allow them to be joined with other DNA molecules. Since the characteristics or traits of organisms are encoded in their DNA, this allowed the DNA sequences specifying a specific trait to be excised from one organism and inserted into a different organism. When combined with techniques developed during the 1980’s for insertion of DNA into the genetic material of plants (known as “transformation”), this allowed specific genes or traits to be transferred from virtually any organism into crop plants. Collectively, these techniques are known as recombinant DNA or rDNA methods for genetic modification of plants and other organisms.
What are the advantages of rDNA methods for genetic improvement of crops? A major advantage is that only the desired trait is transferred. In standard breeding or introgression approaches, all of the genes of both parents are mixed together, even if the transfer of only one gene to the crop plant is desired. Numerous (6-10) generations of subsequent crossing and selection are then needed to eliminate the undesirable traits also introduced from the wild parent, and in some cases it is not possible to completely eliminate linked traits. With rDNA techniques, only the desired gene can be transferred into an otherwise elite variety. The most significant advantage of rDNA techniques is that the gene to be transferred can be obtained from virtually any other organism. In classical breeding, only the genes that occur in the crop species or in closely related species that can hybridize with it are available for crop improvement. With rDNA, genes can be incorporated into the crop that do not occur in the species or its relatives. This has resulted in the two most widely commercialized applications of agricultural biotechnology, herbicide resistance and insect resistance. To confer herbicide resistance, the target enzyme for the action of the herbicide is identified, and then another gene (which can be derived from bacteria, fungi or plants) is inserted that is less sensitive to the action of the herbicide. This single gene change then allows the crop plant to tolerate exposure to the herbicide. Similarly, resistance to some insects has been introduced into crops by transferring the ability to produce a specific protein from a bacterium called Bacillus thuringensis (Bt). This naturally occurring bacterium produces a crystalloid protein that is toxic to the larvae of lepidopterous insects, including corn borer and cotton bollworm. Herbicide and insect tolerance have been widely incorporated into varieties of corn, cotton, soybean and other crops and were planted last year on approximately 100 million acres in the US, Canada, Argentina and other countries. Additional traits, such as resistance to viruses and other diseases, have also been engineered in this way. Together, these products have significantly reduced the application of insecticides and have allowed the use of more environmentally benign herbicides while making soil conserving production practices more economical and attractive to farmers.
While these so-called “input traits” that improve crop production have been the primary commercial products thus far, “output traits” that improve the value and quality of the end products are starting to appear on the market. Many of these will target nutritional quality, and crops with altered oil and protein composition or content are already on the market. Particularly exciting are developments that can have an enormous impact on world food supplies. For example, legume seeds have been engineered to express an inhibitor of insect a-amylases that prevents infestation and damage during storage, which claims a large fraction of commodities in many countries. Rice has recently been engineered to accumulate b-carotene in the endosperm. As b-carotene is converted in the body to vitamin A, this development could alleviate vitamin A deficiency in many parts of the world that rely on rice as a staple, potentially preventing two million deaths each year. Similar efforts are underway to improve the content of vitamin E, iron and other micronutrients in food crops. Various strategies are currently under investigation to improve the fiber quality of cotton as well. Common to all of these products is that the genes responsible for the improvement did not exist within the natural breeding populations of these species, so the only way that these products could be developed is via rDNA methods to transfer the required genes from other organisms.
It is evident that agricultural biotechnology is an extension of a long history of domestication and genetic improvement of crops. The benefits are compelling, and we have only begun to tap the potential of this technology. Nonetheless, acrimonious debate has erupted around the world about the application of agricultural biotechnology. Some countries have placed a moratorium on further product approvals, and have requested segregation of biotech crops from other varieties. Environmental and consumer groups are lobbying for stricter regulation or an outright ban on enhanced varieties. Acts of vandalism against research plots and fields have occurred at numerous locations, including at UC Davis, UC Berkeley, USDA, and private research facilities. Legislation is being prepared for introduction in both California and Congress that would require mandatory labeling of products made from biotech crops. Why all the controversy? Are there risks associated with biotech crops?
There are many voices in the current debate, but opponents of agricultural biotechnology commonly raise some of the following issues:
· Food safety / labeling
· Environmental “contamination”
· Unexpected consequences
· Reduction in biodiversity
· Corporate monopolization of food
· Fear of the unknown
Let’s take a brief look at each of these issues.
Opponents of agricultural biotechnology cite concerns about the safety of foods derived from genetically enhanced varieties. However, the National Research Council of the National Academy of Sciences has studied this issue and in 1989 concluded that “No conceptual distinction exists between genetic modification of plants and microorganisms by classical methods or by molecular techniques that modify DNA and transfer genes, whether in the laboratory, in the field or in large scale environmental introductions.” Thus, our most prestigious scientists have determined that the end products of rDNA techniques do not present a greater risk than the products of classical breeding. The same principle has been reaffirmed by the Food and Drug Administration, which in 1992 issued guidelines for the commercialization of biotech foods asserting that they are “substantially equivalent” to classically derived foods. As such, no additional labeling is required simply to indicate the type of variety used to produce the food product. If the composition of the food is substantially altered, or if there is the possibility that a novel allergen has been introduced into the product, then additional testing and labeling are required by the FDA. All products currently on the market have been extensively tested to confirm that their composition is essentially identical to standard varieties, despite claims by groups opposed to biotech foods that the latter are “untested.” And as described above, all of our crops have been extensively modified in the past by genetic means without the disastrous consequences predicted by some. With over half of the soybeans and over one-third of the corn grown in the US coming from varieties enhanced by biotechnology, many common food products have already contained these ingredients for several years, and no adverse effects on health have been reported. The current policies enforced by the USDA, the FDA and the EPA are reasonable and science-based, and are sufficient to ensure that the products of agricultural biotechnology are at least as safe as traditional foods. In fact, a recent study found that the levels of a specific mycotoxin (fumonisin) produced by fungi that grow on damaged corn grains was markedly reduced in insect-resistant Bt corn relative to a standard variety.
Some argue that biotech foods should be labeled so that consumers can know what they are eating. However, such mandatory labeling could be misleading if it implies that there is a substantive difference between these and other types of foods. In addition, in a pivotal 1996 decision the U.S. Court of Appeals for the Second Circuit found that food labeling cannot be compelled just because some consumers wish to have more information. In overturning a Vermont law that required labeling of dairy products from cows treated with recombinant bovine somatotropin (BST), the court found that such regulation merely to satisfy the public's “right to know” is a constitutional violation of commercial free speech. “Were consumer interest alone sufficient,” the court wrote, “there is no end to the information that states could require manufacturers to disclose about their production methods." Voluntary labeling by companies to show goodwill might be a good consumer relations strategy and perhaps give a level of reassurance and transparency to the regulatory process. And as nutritionally enhanced food products (or improved cotton fiber quality) results from continued research, companies will undoubtedly want to label and market these improved products. Mandatory labeling, however, is unnecessary and would be exceptionally difficult to implement, as the Europeans have already discovered.
Concerns have been raised about the possibility of contaminating the environment by creating “superweeds” or causing the development of virulent diseases by engineering resistance into plants. However, the traits that result in successful weeds are exactly those that have been largely eliminated during the process of domestication. Corn, cotton, wheat and soybeans have no wild relatives with which to outcross, and none of these plants are capable of becoming weeds. In some crops, such as canola or sunflower, the possibility of transferring traits to related species is greater, and the consequences of this for those species has been examined on a case by case basis. However, we have been incorporating disease resistance genes into our crops by introgression for many years, without knowing anything about the mechanisms by which those genes acted, and have not observed the problems that are now being predicted by some for very targeted changes that can be readily monitored.
What about
unexpected consequences for the environment from the release of genetically
enhanced crop plants? Here,
the situation is more complicated and it is difficult to give a definitive
answer. In a complex ecosystem, it is simply not possible to predict all of the
potential interactions and consequences that might occur, so the risk level can
never be reduced to zero. However, we live with many situations where risk is
present, but where we consider it to be acceptable. Driving a car entails a
degree of risk, yet many people drive on a daily basis. When we think about the
risks associated with agricultural biotechnology, we can compare them with other
practices that we have adopted, often with great success, such as the
introduction of specific insects as biological control agents. Here, we have
purposely introduced a foreign insect or pathogen to control a pest, and while
we can thoroughly test the anticipated consequences under controlled conditions,
we cannot guarantee that there is no possibility of unexpected consequences.
Nonetheless, if the benefit is sufficient, and the risk is judged to be
acceptable, we have introduced numerous foreign organisms for this purpose. And
there have been some mistakes. Overall, however, the successes have outweighed
the failures and we continue to utilize this approach, because when it works, it
removes the need for less environmentally compatible measures. While past
history cannot provide certainty, experience is the best guide we have here, and
it says that we should proceed prudently, with due caution and continued
monitoring, but the risks are not sufficient to ban the application of the
technology.
The potential for loss of biodiversity is often cited as a criticism of the spread of biotech crops. However, this seems rather misguided. The greatest threat to biodiversity is the loss of habitats that harbor complex ecosystems, not the substitution of one cultivated variety by another in an agricultural system. Nobel Peace Prize winner and agriculturist Norman Borlaug has noted that “had 1961 yields still prevailed today, three times more land in China and the USA and two times more land in India would be needed to equal 1992 cereal production.” With the present population of 6 billion expected to increase to as much as 10 to 12 billion in the next 30 years, the only way to preserve habitat for the earth’s diversity of creatures is to intensify the productivity of land already in agricultural production. We will need all of the tools at our disposal, including biotechnology, in order to do this.
While additional testing and monitoring can answer scientific questions about the development of agricultural biotechnology, some concerns are not based on science or biology. Much of the rhetoric of anti-biotech groups is focused on the corporate involvement in the development and sale of these products. The Environmental Liberation Front, which has claimed responsibility for several acts of vandalism against universities engaged in biotechnology research, has stated that “Genetically modified organisms exist for one reason, the drive for profit by large multinational corporations.” And there is no doubt that the potential for economic returns has played a significant role in the development of these products. It is also clear that mistakes have been made in the marketing of these products that have exacerbated the public’s concerns and fears. However, the rapid adoption of these products by farmers indicates that they are benefiting from this technology, and the environmental advantages have been documented as well. The acquisitions and mergers of the past three years have raised concerns about the monopolization of crop germplasm by relatively few companies, and this could be a real concern, depending upon how the underlying technologies are made available to the industry. On the other hand, consolidation has occurred in virtually all segments of our economy over the same time period in search of greater productivity and efficiency. Americans on average now spend only 12% of their income on food, largely as a result of the incredible productivity and efficiency of our agricultural system. Only 2% of our population are actively involved in agricultural production, with the result that the vast majority of people have no contact with or understanding of current production methods. The public’s image of agriculture is about 100 years out of date, idealizing a type of system that was feasible when 80% of the population was engaged in farming, but which doesn’t match current economic realities in agriculture.
And finally, there is simply fear of something new and unknown. No doubt all of us can remember knowing someone who was scared of microwave ovens when they were first introduced. Now you can hardly find a home without one. Biotechnology is an extremely powerful technology that will have an impact on our society on a magnitude similar to that of computers. No one could have predicted with accuracy that the Internet would develop when the first integrated circuit was invented. Similarly, profound changes will result from biotechnology, even more dramatically in the medical sciences than in agriculture. Many people are uncomfortable with change and with the pace of change, and their concerns need to be taken seriously. We must be sure that the products that we develop and use are beneficial to the producer, the consumer and the environment. We need to be more aggressive in publicizing the positive benefits of agricultural biotechnology, rather than taking the path followed by some prominent companies by publicly (and hypocritically) rejecting biotechnology in the face of largely untested claims of consumer uncertainty. For example, a recent opinion poll sponsored by Philip Morris and the American Farm Bureau Federation found that only 37% of consumers have heard more about the benefits of biotechnology than the drawbacks, but that 73% would support biotechnology if it would reduce pesticide use. While pesticides are essential tools for high agricultural productivity, expanding alternatives to their use is a clear benefit of biotechnology that could be more widely publicized.
This is an extremely important time in the development of agricultural biotechnology. The initial “proof of concept” products have met remarkable market acceptance, at least among farmers who are the primary beneficiaries of these products. These products work, and the potential for further development of this technology is virtually unlimited. Next year, the cotton industry will see the largest introduction of transgenic crops yet into California, and will inevitably be the focus of attention as the public debate intensifies during both the cropping and the legislative season. It is critically important that this industry demonstrates that it is a trustworthy steward of this technology. Guidelines for insect refugia, chemical applications, isolation distances, etc., must be known and adhered to, because there are those who would like nothing better than to find violations that could be mass marketed with the message that neither the corporations nor the farmers can be trusted with this technology. Right now, we have to be thinking long-term rather than short-term. Don’t jeopardize the long-term benefits of this technology for the sake of short-term profits. Instead, let’s use this year to demonstrate the advantages that agricultural biotechnology can bring to all stakeholders. If there are problems, let’s document them so that they can be avoided in the future. The greatest risk at the moment is that fear (and those who are using fear and intimidation) will be able to stop or delay research and development to answer the questions that have been raised and to develop new products that will benefit farmers, consumers and the environment.