April 1998
Biotechnology: The Next Revolution in Agriculture?
By Tracy Sayler
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Prairie Grains is the
official publication of
the Minnesota
Association of
Wheat Growers,
North Dakota Grain
Growers Association,
South Dakota Wheat,
Inc., and the
Minnesota Barley
Growers Association.
Historians may someday look back at biotechnology as the
single greatest event to revolutionize agriculture. Indeed, many view biotechnology as the best answer for world food security, and everything in between: more productive crops and livestock from the same land base, with more nutrition, that require less water, fertilizer, and pesticides. Better yields and better markets for producers, and healthier, safer, more abundant food for consumers.
The area of cultivated land in the world devoted to genetically-modified crops is expected to double from 34 million acres last year to 84 million in 1998, and 150 million acres by 2000, according to French agriculture experts. Of the world's farmland growing genetically-modified crops, 88% will be in the United States, 6% in Latin America and 6% in Asia.
Soybeans are the foremost genetically-modified crop, followed by corn. The Bowditch Group, a Boston consulting firm that tracks ag technology trends, estimates that 30% of soybeans planted in North America this year will be Roundup Ready, or resistant to glyphosate. About 10% of the North American corn crop in 1998 will be Roundup Ready or Liberty Link (glufosinate) resistant. Bt corn, containing the Bacillus thurigiensus gene to repel the European corn borer and similar insects, will also take up about 10% of the 1998 North American corn acreage.
The Bowditch Group estimates that Bt cotton will be about 35% of the North American cotton acreage, and about 27% of the cotton acreage will be Roundup Ready. About 15% of canola acreage will be Roundup Ready, and 30% of canola will be Liberty Link resistant.
The growth of genetically-engineered field crops is projected to continue. The reason these crops are so widely and eagerly accepted is that they offer better, safer, and easier pest management, as well as significant cost savings to farmers. Roundup Ready soybeans, for example, can typically save farmers $13/acre or more.
"Without use of genetic engineering and other biotechnology tools, it is no longer possible to compete technologically in the seeds, crop protection, or animal health industries," the Bowditch Group flatly concludes.
How it works
Since 1984, genetic engineering has been introduced as an additional method to alter the inherited traits of plants, according to Ag-West Biotech Inc., a Saskatchewan biotech R&D company. Genetic engineering is a process by which genes (the parts of a cell that provide blueprints for inherited traits) are "cut" from the cells of one organism and "pasted" and integrated into the cells of another organism. Once the cells are transformed, they are grown into new plants capable of "expressing" the desired characteristic. Genetic engineering allows plant breeders to obtain genetic traits from sexually incompatible organisms, such as entirely different plant species, bacteria or even animals.
Oilseeds respond more readily to biotechnologies that use bacteria to "ferry" genes through the cell wall of the target plant. The biotech technique that works best for cereal grains was developed in the late 1980s by scientists at Cornell University, who invented a particle bombardment device (a "gene gun" used to "shoot" genes through cell walls) that is more effective in genetically modifying cereal grains.
Biotech wheat and barley
Novartis and Monsanto are the main private industry players in transgenic small grains research and development. Both companies are researching anti-fungal genes for scab, and other qualities to decrease the need for inputs such as crop protectants, and enhance specific end-use qualities as well.
Monsanto several months ago announced a plan to collaborate with Agriculture Canada to develop Roundup Ready wheat. Monsanto also owns HybriTech Seed International that is developing hybrid wheats.
Research on wheat hybrids actually goes back to the 1950s, but only in recent years with better research techniques has the commercialization of hybrid wheats been closer to reality. Wheat hybrids promise better yields, more stress tolerance, better adaptability over a range of environments, more efficient use of water and nutrients, and better disease resistance through a technique called "gene pyramiding," which is the incorporation of two or more genes for resistance to one disease.
HybriTech is marketing three soft red winter wheat hybrids and 10 hard red winter wheat hybrids under the "Quantum" seed moniker. The advancements in spring wheat hybridization, however, still do not justify the higher seed costs, and it will be several years yet before hybrid spring wheats are developed enough to be commercialized.
Public wheat and barley transgenic research is scattered across several land grant universities and USDA Agricultural Research Service labs across the country. Researchers are working on genetically engineering several traits, including better bread-making quality in wheat, better pasta quality in durum, and better malt quality in barley.
Further, researchers are looking at resistance to drought, and changing the starch composition of wheat to make wheat starch a more valuable co-product of wheat gluten and a better competitor with corn and potato starch in some applications, according to USDA-ARS research geneticist Ann Blechl, Albany, CA. Engineering resistance to insects and diseases that can affect wheat and barley is also in place. "Probably the most urgent need right now is for resistance to fungal infection, particularly scab and Karnal bunt," says Blechl.
USDA-ARS barley geneticist Lynn Dahleen says her laboratory in Fargo, ND and others are focusing on identifying the genes and mechanisms by which scab resistance can be developed in wheat and barley.
There are several approaches being used to achieve this goal, including the mapping of scab resistance genes with molecular markers. Molecular markers can be thought of as road signs or tags to mark regions of the plant chromosomes that carry scab resistance genes.
"The first step in this process is to identify the tags for the genes by 'mapping,' or determining the linear order of the markers and genes in the plants' DNA," says Dahleen. "Scab tolerance is controlled by three or more genes, each with small effects. The breeders can't easily tell which genes are in a plant using field tests. Instead, we can test for these molecular marker tags in the lab to quickly identify plants that are likely to have the resistance genes. We also can use these tags to select among lines with resistance for other desirable traits, like yield and quality, helping to speed up development of new cultivars."
Gary Muehlbauer says his program and others involved with molecular scab research want to identify genes in wheat and barley that are involved in the scab defense response, identify antifungal genes from wheat, barley and other organisms, and genes that can detoxify vomitoxin. It's no easy task: barley has about 25,000 genes, and hard red spring wheat between 50,000 and 75,000 genes.
Durum wheat has about 50,000 genes, fewer than HRS wheat. That may be a plus in the research effort to solve the scab problem in durum. No resistant sources for scab have been identified in durum varieties from around the world, according to NDSU molecular geneticist Shahryar Kianian, who is using a wild relative of durum (Triticum dicoccoides) that grows in the Middle East as a potential source to transfer scab resistance genes to durum. Transgenic research will ultimately provide additional genes for resistance in durum.
A number of proteins have been identified that may inhibit growth of the Fusarium fungi that cause scab, or reduce vomitoxin in grain. Transforming the genes that encode these proteins into cultivars will enable the ultimate goal: transgenic wheat and barley plants that are scab resistant.
"Transgenic material still needs to be incorporated into a breeding program. The crop breeding effort will get us part of the way down the road to scab resistance, transgenics will get us the rest of the way. I don't think either one will do it alone, under severe disease conditions," says Muehlbauer.
South Dakota State University molecular biologist Tom Cheesbrough sees molecular biologists as just one spoke in the wheel, and plant breeders as the hub of the wheel of variety improvement.
Among wheat biotech projects in the works at SDSU's Northern Plains Biostress Laboratory in Brookings: wheat with genes for a protein that kills at least three kinds of aphids and also stops them from reproducing, and winter wheat with genes added for cold tolerance that is better able than current varieties to survive extreme winters.
When the recovery rate of cells in tissue culture successfully altered with new genes is one in 10,000, Cheesbrough says that a land-grant university like SDSU, working with a limited budget, must "choose its battles carefully," and SDSU does that by focusing on problems specific to South Dakota farmers, rather than national or international problems.
Biotech concerns
The general public in Europe has not been as fast to accept biotechnology as people in the United States and Canada, mainly due to fears of the unknown, and that the technology could be misused in a "mad science" type of way. The key to easing misperceptions is consumer education, says Stacey McCauley, who tracks biotech issues for the Wheat Export Trade Education Committee, Washington, D.C.
Last September, the Biotechnology Initiative was formed to target European consumer acceptance of modern biotechnologies in the food chain. With an $8.3 million commitment in 1998 and more expected, the initative is funded by the American Soybean Association and multinational companies including Monsanto, Novartis, Dupont, Cargill, Nestle, and Coca Cola, which has an interest in sweeteners.
McCauley says that last year, the European Union began requiring genetically-modified products to be labeled as such. But the labeling need not be negative, she points out. In fact, the labels have been used to convey more positive messages such as "produced with modern biotechnology which requires less pesticide and water use." Perceptions may already be changing. Research indicates that although European consumers say they are skeptical of genetically-modified products, they are buying them nonetheless.
There are still questions about how biotech products will be regulated. For example, language in a proposal from the Environmental Protection Agency would have genetically-modified plants go through the same EPA registration process used for chemical pesticides. The proposal is still being debated, says McCauley.
Consolidation is another concern. Seed and chemical companies are partnering up and forming joint ventures (DuPont and Pioneer Hi-Bred; Mycogen and Dow Chemical Co. are two examples of corporate biotech marriages) in the race for biotech marketshare.
High research and development costs (it costs $250,000 to $100,000 just to insert a gene) excludes smaller private seed and chemical companies and some public research programs from biotech.
Further, as companies race to develop biotech ag, research is becoming more secretive, and product patenting is increasing. This worries some crop scientists, including USDA-ARS wheat geneticist Bob Busch. "The patenting of genes and transgenics is a real concern, as germplasm exchange and the sharing of results to advance research knowledge is becoming threatened," says Busch.
The public's stake in biotech may be furthered by the "USDA Food Genome Initiative," a sweeping plan that is being described as "an essential part of the USDA research agenda." The initiative will include basic and applied biotech research of plant and animals, with funding proposed for fiscal year 1999 at $40 million, $70 million in 2000, climbing to $100 million in 2001and thereafter.
Future of Biotech Takes Three Paths
Future bio-engineered commodities and products might be categorized in three broad groups, according to Kyd Brenner, vice president of the Corn Refiners Association, Washington, D.C.:
1) Products with improved production traits - In the next few years, look for these biotech advancements:
A transfer of herbicide and pest resistance from already-modified corn, soybeans and cotton into commodities such as wheat, sugar beets and sunflowers.
Virus resistance and mold resistance transferred from fruit crops into the major grain and oilseed crops, reducing the potential for fungal contamination and associated mycotoxin problems.
The ability of a plant to help regulate changes and differences in water and soil quality will be introduced to major crops. Factors such as drought and salinity may be better managed.
Minor changes in nitrogen fixation and utilization rates.
2) Products with improved output traits - Major types of output changes that can be expected:
Crops designed to be high in traditional qualities such as oil, starch, sucrose or gluten for increased value to particular processors and end users.
Crops altered to increase their nutritional value or functionality. For example, high oleic-acid soybeans are coming to the market this year offering food processors oil with an improved nutritional profile.
Crops which have been altered to improve quality and functional factors such as oil stability and flavor, starch and protein structure or fiber size and color.
Crops which have been altered to improve their processing characteristics. Genetic engineering may allow oils, fiber, starch and sugars to be extracted from crops during processing with less energy input and lower environmental impact.
3) Crops that produce entirely new functions, qualities, or benefits - Still years away, in most cases these kind of products are "little more than twinkles in the eyes of researchers" says Brenner, and unlike alterations which can be controlled by manipulating a single gene, or stacking several single gene traits, these products may require a new level of sophistication in genetic manipulation. The possibilities:
Biologically-based polymers which can be substituted for petroleum products.
Foods designed to be used in disease prevention. Future vegetable, fruit and grain crops may be "nutraceuticals" or vehicles for boosting intake of carentenoids, antioxidants, vitamin E, folates and other micronutrients which have been linked to prevention of cancer, coronary disease and degenerative nerve diseases.
Crops designed to produce high-value pharmaceuticals and antibiotics. Pharmaceutical firms are actively investigating plant-based production systems which could replace traditional fermentation processes.
Brenner says a key question which remains is how all these new technologies will be integrated into the agricultural system. There must be financial incentives throughout the food chain, including seed developers, producers, distributors, processors, and end users. Also, better segregation and delivery will need to be developed. Brenner says existing grain-handling transportation and storage may be adapted, and in other cases, direct farm-to-processor contracting and delivery.
Even with the development of major bio-engineered crops, traditional commodity markets will always exist. "Our system has been built as a source of a high quality raw material, available every day of the year, in almost any location. While processing industries adapt new technologies, there is a large base of business which is absolutely dependent on this commodity market," says Brenner.
Cereal Disease Lab
Bioengineering for scab resistance
The name of the USDA Agricultural Research Service's Cereal Rust Lab was changed recently to the Cereal Disease Lab, reflecting an expanded focus that will include more research on scab.
Federal research at the CDL, with Dr. Kurt Leonard as Research Leader, will compliment work conducted at the University of Minnesota, and focus on scab research areas that need more attention. To solve scab, the disease needs to be better understood; thus, two federally-funded fungal geneticists will be joining the CDL this year to research some of the basic questions about scab that still need to be addressed, such as why scab is such an aggressive fungal disease, whether the fungus has adapted, and are there different races of the disease.
In addition to basic research on scab, the CDL is also conducting applied research, including the evaluation of cloned genes for use in bioengineering scab resistance. It can take about a year to incorporate a new gene into a wheat plant. It is also expensive, in the ballpark of $50,000 to $100,000 per gene. The cost may be less at some private companies with larger plant transformation facilities.
When a gene is put into a plant, scientists must be mindful about where in the plant the gene will be expressed, says CDL researcher William Bushnell. "The gene needs to be expressed in the plant tissue where disease resistance is needed. We need more work on developing promoters to 'turn on' genes in response to infection," he says.
Thus, if a gene is inserted into a wheat plant that offers more resistance against the spread of scab within the wheat head, the gene would "kick in" when the genetically-engineered wheat plant needs this resistance most, during head development.
Defining Biotech Talk
Biotechnology: "Bio" is derived from "bios," the Greek word for life; "technology" is the application of scientific knowledge to practical purposes.
Bt: Bacillus thuringiensis, a naturally-occurring, soil-borne bacterium that produces crystal-like proteins which kill certain insects when ingested. Plant geneticists create a Bt crop by inserting a gene that encodes a Bt protein into the host plant's own DNA.
Chromosome: The physical structure into which DNA is organized and on which genes are carried.
DNA: Deoxyribonucleic acid, which contains the genetic information found in most organisms.
Genetic engineering: The transfer of a gene from one organism to another.
Gene: A functional hereditary unit that occupies a fixed position on a chromosome, which influences one trait or several related traits of an organism; for instance, whether a wheat variety is tall or a semi-dwarf.
Genome: The total genetic makeup of an organism. For example, all the genes of a wheat variety that influence its growth and development, agronomics and end-use qualities.
Genomics: The study of the structure and function of the genome.
Gene Mapping: The localization of genes to specific places on chromosomes or pieces of DNA.
GMOs: Genetically Modified Organism.
Hybrid: A cross between two genetically dissimilar parents.
Transgenic plant: A plant into which a gene has been transplanted by genetic engineering.
Transformation: The process of introducing foreign DNA into plant cells, or the change in the genetic structure of an organism by the incorporation of foreign DNA.
Wheat, barley leaders seek federal funding for scab
Wheat and barley leaders continue their quest to seek more federal funding for a national scab research initiative.
The fungal disease has caused catastrophic yield and quality losses in at least 12 states in the 1990s: Indiana, Illinois, Kansas, Kentucky, Michigan, Minnesota, Missouri, Nebraska, New York, North Dakota, Ohio, and South Dakota. Losses to producers alone are estimated in the billions.
"The mission of the Scab Initiative is to develop, in the shortest period of time possible, control measures that can minimize the threat of scab to the producers, processors and consumers of wheat and barley," says Rick Ward, Michigan State University wheat breeder. Ward serves as co-chair of the national scab research initiative, along with Tom Anderson, a Barnesville, MN grower.
Ward says adequate federal funding will address seven research areas: epidemiology/pathology; food safety/toxicology; uniform nurseries, germplasm introduction; transgenics; and communications.
Congress has appropriated $1 million this year (FY98) to help address the scab problem, says Mike Davis, president of the American Malting Barley Association and member of the Scab Initiative Steering Committee.
"The Administration's budget proposal for next year (FY99) retains this funding and proposes an increase of $600,000 for scab research as part of the Infectious Diseases Initiative," he says. "This support is appreciated, but it is not nearly enough to get the job done." Davis says the Scab Initiative is asking Congress for an annual appropriation of $5.2 million in each of the next five years to battle the scab problem through research.
For more information about the U.S. Wheat & Barley Scab Initiative, visit the web site http://www.scabusa. org. n