Illinois Fertilizer
Conference Proceedings
January 28-30, 1991
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Don Holt1
Agricultural biotechnology is the application of molecular biology and, especially, molecular genetics to solving agricultural problems and exploiting agricultural opportunities. Biotechnology research leads to new and improved agricultural inputs. Biotechnology is not a panacea. Ultimately, it will benefit agriculture by enabling a number of relatively small, incremental improvements in technology, just as agricultural research has in the past.
Biotechnology provides new opportunities to build pest- and stress-resistance into plants. Such developments may reduce the demand for pesticides. On the other hand, genetic engineering of crops for herbicide resistance may increase use of some broad spectrum, environmentally-benign herbicides. Biotechnology research will produce crop varieties with special characteristics that increases their value as grain and forage. Growers can justify greater inputs of fertilizer and chemicals to production of higher value crops.
Biotechnology will change patterns of fertilizer use. The most profound changes will come about if and when major cereal crops are. enabled to fix their own nitrogen. Closer at hand are biotechnology tools for screening crops for nutrient-uptake efficiency and nitrogen-fixing microorganisms that are more efficient and productive.
Microbial biotechnology, particularly as applied to industrial fermentation, will increase the demand for crops and crop residues as raw material for manufacturing food and non-food products. This, in turn, will increase the demand for fertilizer and chemicals. Likewise, biotechnology developments in animal agriculture are likely to increase the overall demand for animal products, thus increasing the need for feed and associated production inputs, including fertilizer and chemicals.
Illinois fertilizer and chemical dealers will not benefit from biotechnology unless Illinois farmers can use this important technology to gain a competitive edge in international agricultural markets. Illinois must enlarge and improve its institutional capacity for adaptive research and extension in order to capture the benefits of world-wide investment in biotechnology research.
In biotechnology, knowledge about molecular biology, especially molecular genetics, is used to modify organisms in economically or socially important ways. Changes induced in agricultural organisms by biotechnology will inevitably effect the fertilizer and chemical industries. For centuries, agriculturalists have been modifying plants and animals, and indirectly microbes, by breeding and selection
Biotechnology, which is based on better understanding of the specific mechanisms by which biological traits are encoded, inherited, and expressed in organisms, provides more powerful tools and methods for breeding and selection. Biotechnology also provides tools and methods for enhancing or suppressing genetically-controlled traits, identifying and treating genetic diseases or other abnormalities, creating more effective vaccines and other pharmaceutical agents, identifying and characterizing specific organisms, and efficiently screening organisms for specific traits.
In this paper, I describe several possible scenarios of change resulting from biotechnology. Some of the scenarios might lead to less use of agricultural chemicals and fertilizers. Some would lead to greater use of at least some of these materials. Some biotechnology scenarios are already unfolding on the agricultural scene. Some are far in the future.
It is still quite difficult to predict exactly when various biotechnology initiatives are going to result in commercial realities. Perhaps the following discussion will at least reveal developments that people in the fertilizer and chemical industries should watch. In any case, change is more likely to be driven by economic, social, and political forces than by biotechnology itself, which only creates possibilities.
Biotechnology is a way to increase genetic variation by recombining existing genes (segments of DNA controlling specific traits), just as in conventional plant breeding and genetics. Having increased genetic variation among organisms, scientists apply selection pressure and select the most desirable new types. In general, biotechnologists, like conventional plant breeders, manipulate genes that already exist or that have been induced by mutation. In a few cases, biotechnologists may be able to produce new or modified genes that did not exist in nature before.
Biotechnology, like conventional plant breeding and genetics, results in organisms with increased genetic potential for productivity or quality. It does not, however, guarantee that the potential will be realized. To realize fully the genetic potential of a crop, for example, requires excellent management of the total crop system, including variety selection, fertilization, tillage, establishment, culture, pest control, harvest, storage, processing, distribution, marketing, and utilization.
In fact, many genetic changes in agricultural crops and animals will not be effectively implemented until there have been changes in the agricultural infrastructure. For example, until the grain storage and shipping system provides efficient ways to preserve the identity of grain with special characteristics, there will be little advantage gained by producing crop varieties with these special traits.
Biotechnology differs from conventional plant breeding and genetics in enabling easier manipulation of specific traits. For example, biotechnology should make it possible to move a gene conferring resistance to a specific disease from an unadapted foreign soybean variety to a well-adapted, productive domestic variety without the generations of backcrossing required by conventional approaches. This should reduce the time required to produce improved varieties, thus reducing the cost and expanding the scope of improvement.
Among the most important potentials of biotechnology is to move genes between species, even completely unrelated species. This creates a great potential for producing crops and animals with totally new characteristics of economic and/or social value. For example, several scientists are working to characterize the genes and control mechanisms enabling atmospheric nitrogen fixation, with the goal of transferring that capability to plants. While this potential is far off, it probably will be accomplished eventually. Needless to say, such a change will have profound implications for the fertilizer industry.
Biotechnology is actually a broader, more vaguely defined activity than plant breeding. It is more a set of procedures and processes than a discipline. Many scientists who would not be classified as biotechnologists by training and experience are using biotechnological techniques in their research. In this respect, biotechnology is pervading almost all areas of biological research. It is also the subject of much social, legal, and philosophical investigation.
Biotechnology research is generally product-oriented, that is, it will tend to produce new and improved products, such as crop varieties, animal breeds, vaccines, pharmaceuticals, diagnostics, and biocontrol agents. This is why it is of such great interest to private firms.
The short-term commercial potential of biotechnology, like many promising new technologies, was tremendously oversold, a classic example of "hype." Many early providers of venture capital for biotechnology initiatives can attest to this. Participants in a conference on the economic implications of biotechnology concluded that it will be 25 years before biotechnology will be the dominant technology and a major economic force in commercial agriculture.
Potential biotechnological innovations are particularly interesting and dramatic. Our society likes dramatic innovation, which occurs in laboratories and news media, rarely in practice. Ultimately, biotechnology advances will be manifested in practical agriculture as relatively small, incremental improvements in productivity, efficiency, and quality, as was the case with dramatic innovations of the past, including hybrid corn.
Currently, the effective application of biotechnology to agriculture is somewhat inhibited by two misconceptions. One is that the potential benefits of biotechnology are outweighed by the risks associated with its use. The other is that biotechnology, somehow perceived as more "natural" than chemicals, is the only acceptable way to achieve such goals as pest control. Both of these generalizations are far too broad to be useful in making decisions about biotechnology.
There are several reasons why it is easier to conceive biotechnology strategies than to implement them. One is that it is difficult to transfer specific genes or gene systems among plant, animal, and microbial cells, get them incorporated into the gene compliment of the target organism, and get them expressed in that organism.
Certain bacteria and viruses are sometimes used as vectors to transport genes into plants and animals. Sometimes a special gun is used to shoot fragments of DNA into cells. Only recently has gene transfer become relatively routine in some species. Other species, including corn and soybeans, remain relatively difficult to transform through genetic engineering.
Many important crop and animal traits involve several genes. Biotechnologists are not as yet able to transfer these multigenic traits successfully. Nitrogen fixation, for example, is controlled by as many as 19 genes. Yield and drought resistance are complex traits affected by many genes. So far, biotechnology works best with single gene traits. On the positive side, some quality improvements, such as improved amino acid balance, may be achieved by manipulating relatively few genes.
Besides genes that control specific plant traits, there are elaborate genetic systems that determine where in the plant and when during its life cycle specific genes will be expressed, To manipulate traits, the biotechnologist must transfer not only the genes that control the traits, but also the genes that control the expression of other genes. If, for example, a gene that confers resistance to a leaf-feeding insect was transferred to a susceptible crop variety and was expressed only in the roots, the gene would not confer the desired resistance.
A major limitation to applying biotechnology techniques is the amount of background
research that must be done. Usually, before an organism can be usefully altered
by biotechnology, it is necessary to know the biochemical mechanism by which
a desired trait is expressed in the organism, the specific enzymes (biochemical
catalysts)
that constitute the mechanism, the specific genes that code for those enzymes,
the mechanisms of inheritance of those genes, and the genetic control mechanisms
that turn those genes on and off.
Biotechnology provides greater opportunity to build insect and disease resistance into crops than is possible with conventional breeding and genetics. Also, crops are being genetically engineered to be resistant to broad spectrum herbicides, thus simplifying weed control. Other important applications of biotechnology to crops include improving crop quality, creating special, higher value types of commodity crops, and eventually, engineering crops to fix atmospheric nitrogen.
Disease, insect, and herbicideresistance
To the extent that crops are genetically engineered with resistance to major insect and disease pests, one would expect less use of insecticides. Much biotechnology research is directed to improving insect and disease resistance of crops. These are complex research and development undertakings, however, and will not cause dramatic changes in the near future. The first such applications should be commercially available by the mid-1990's.
A typical approach is to find an organism that produces a substance that is toxic or otherwise inhibitory to an important disease or insect pest. Then the genes controlling production of that toxin are moved to the crop so the crop makes the toxin. For example, Monsanto scientists transferred a gene from a bacterium to tomato. The gene causes the tomato plants to synthesize a toxin that paralyzes the digestive system of the tomato horn worm, a serious pest that defoliates tomatoes.
Steve Ferrand, University of Illinois plant pathologist, proposes to genetically engineer plants to overproduce chitinase, an enzyme that breaks down chitin in the walls of some fungal cells, thus destroying those cells. This could be a powerful approach to enhancing plant resistance to fungal and other diseases, including the soybean cyst nematode. Monsanto scientists produced tomatoes that make the coat protein of tobacco mosaic viruses, which cause disease in several species. When an excess of virus coat protein is in a plant cell, the virus cannot shed its coat, and thus cannot damage the cell.
Major efforts are underway to make crops resistant to broad spectrum but environmentally-benign herbicides. The result will be greater use of certain herbicides and less use of others, including some that are currently used widely. To illustrate, major efforts are underway in public and private research and development groups to make varieties of several important crops resistant to glyphosate, a rapidly degraded herbicide that previously was lethal to virtually all plants.
The principal difficulty in genetically engineering glyphosate resistance is getting the necessary genes into and functioning in the genetic system of the crop. Once the trait is installed in a crop variety, it should be relatively easy to move it to other varieties by conventional breeding techniques.
There may be political difficulties with creating crop resistance to broad-spectrum herbicides. Some environmentalists are particularly apprehensive about this approach to weed control, arguing that it will increase the use of chemical pesticides. Increasing the use of a pesticide is not necessarily bad, however, if the relative risk of using the pesticide is low. Benefit/risk analysis should be performed in each individual situation.
Improving crop quality
To the extent that biotechnology enables plant breeders to develop new, improved varieties of crops that are better suited for specific uses, seed and grain producers may be able to serve niche markets with differentiated products=. Even more important, some seed and grain producers may achieve differentiation in the vast commodity markets for feed, oil, starch, protein, and renewable sources of liquid fuel.
Other things being equal, developments that increase the unit value of grain justify higher levels of productivity-enhancing inputs, including fertilizer and chemicals Suppliers of inputs stand to gain if the farmers they serve achieve differentiation in either niche or commodity markets.
Efforts are underway to improve the quantity and quality of oil, protein, and carbohydrate in cereals and soybeans, using biotechnology. A consortium including Dupont, Pfister Hybrids, and the University of Illinois is developing high-oil corn varieties for use as feed and to serve oil markets. Interestingly, high-yielding, high-oil corn produces more oil per acre than high-yielding soybeans.
Other examples include research of Ron Phillips at the University of Minnesota, who is working to increase the methionine content of corn protein, which normally is of relatively low quality. University of Illinois scientists Ted Hymowitz and Ed Perkins and Iowa State University scientists are learning to manipulate the fatty acid composition of soybeans by genetic engineering. The objective is to produce soybean oil that emulates the desirable characteristics of competing oils, including canola and palm oils.
Biotechnology and fertilizer
There are a few biotechnology research efforts underway that will directly effect fertilizer use. Among other possibilities, biotechnology provides ways to screen crop varieties for those that have a lower requirement for some mineral nutrients. University of Illinois scientists Jack Widholm and Cecil Nickell found that when soybean tissue samples representing several varieties are placed on iron-or manganese-deficient media, the tissue from some varieties grows better than others. The results of such tests are highly correlated, with field tests on deficient soils, but can be conducted much more easily, faster, and less expensively..
Obviously, biotechnology research leading to higher protein levels in grain will lead to higher nitrogen needs per unit of grain produced. To the extent that biotechnology leads to higher yields, more potash and phosphate will be need to replace what is removed by crops. The increased demand per acre for these nutrients might be offset by fewer acres required to meet market needs.
Among major agronomic crops, only soybeans, alfalfa, and clover can be grown commercially without supplemental nitrogen in the form of fertilizer, manure, or nitrogen carried over from a previous legume crop. Bacteria hosted in root nodules by these legume crops convert atmospheric nitrogen to plant-available forms and provide it to the host plants.
If the capacity to fix atmospheric nitrogen can be transferred via biotechnology to other major agronomic crops, the demand for commercial nitrogen fertilizer will decrease significantly. Scientists are approaching this technological challenge from three general directions.
Several groups are working to improve the efficiency of nitrogen-fixing microorganisms, so that larger amounts of plant-available nitrogen can be provided for host crops or left to carry over to subsequent crops. The research involves both organisms that live in root nodules and those that live independently in the soil. Some progress has already been made using this approach.
Researchers are trying to develop new strains of corn and other non-nitrogen-fixing crops that will host nitrogen-fixing microorganisms. They are also working to produce new strains of nitrogen-fixing microorganisms that will colonize these crops. This is difficult because the nitrogen-fixing microorganisms are quite specific for the host crops. To overcome this constraint, scientists must understand the biochemical and biophysical reasons for host specificity.
Perhaps the most desirable and most difficult approach is to transfer genes controlling nitrogen fixation from microorganisms to crop plants, so the biochemical mechanisms of nitrogen fixation exist in the plant cells themselves instead of in the microorganisms. This would eliminate the need for nodules and avoid the problems caused when environmental conditions are satisfactory for the crop but unsatisfactory for the nitrogen-fixing microorganism the crop is hosting.
Some have speculated that it would be better if the nitrogen-fixing mechanism were located in leaves rather than being attached to roots. In that position, it would be closest to the carbohydrate (energy) source and to ample supplies of atmospheric nitrogen. However, nitrogen-fixation is an anaerobic (strongly inhibited by oxygen) process and might not function in the aerobic environment within leaves.
It will be decades before agricultural nitrogen needs can be met by biological nitrogen fixation, if ever. If it comes about, this change would drastically reduce the amount of energy required to grow crops. A large portion of the total energy required is used to manufacture nitrogen fertilizer. There might be some serious disadvantages. At this point, no one can predict the environmental effects of great increases in biological nitrogen fixation. For example, if all crops produced their own nitrogen, would too much nitrate find its way into the water supply?
Since microbes generally have less genetic material, have less complex genetic and physiological systems, and reproduce much faster than larger organisms, more progress has been made in genetically engineering them than other organisms. Most of the commercial applications have been in medicine and industrial fermentation.
One microorganism, a bacterium, played a key role in the first controlled genetic transformations of plants. This bacterium, which causes crown gall disease, is used to carry foreign genes into certain plants. In its natural state, it infects plant cells and inserts some of its own DNA into the plant DNA. Because of this genetic transformation, the plant grows a tumor-like structure or gall, in which the bacterium lives and reproduces.
Using biotechnology, scientists first substitute some gene of interest for the gallmaking gene in the bacterium. Then the bacterium carries that gene into the plant. This bacterium only infects certain broadleaved plants, so other mechanisms of gene transfer had to be developed in order to transform other plants, such as corn.
One of the first applications of biotechnology to agriculture was the development of the so-called ice-minus bacteria. Certain types of bacteria that live on plant leaves serve as nuclei where ice crystals develop at near-freezing temperatures. Genetically altered bacteria do not foster ice crystal development. When applied to leaves of some crops, these altered bacteria compete with and replace native bacteria, thus reducing frost damage. The ice-minus bacteria will soon be available for practical use. This development will be most useful in climates where frosts are rare and especially destructive.
Engineering microorganisms to control pests
Some biological control strategies involve genetically engineering insect pathogens to make them more effective in controlling insect pests. Some microorganisms are being transformed to make them more destructive of other microorganisms. For example, a fungus that lives harmlessly in plants has been transformed so that it produces"a substance toxic to other fungi that cause seedling diseases.
In seed treatment, the transformed fungus is forced under the seed coat, where it produces the toxin. The toxin wards off certain seedling diseases, thus improving germination and establishment. This treatment could substitute for chemical seed treatment in some situations.
Another microorganism that naturally colonizes the vascular systems of certain perennial grasses was transformed to produce an insect toxin, the same one used to control the tomato horn worm. When properly applied, the microorganism will colonize corn plants, offering some protection against corn borers. The microorganism is not passed through the seed stage of corn, so it would have to be applied anew in each generation to achieve protection. This and similar developments could reduce the need for chemical control of insects.
The major deterrent to genetic engineering of microorganisms is the public fear that some microbes will be accidentally modified so as to be very destructive when released into the environment. Some people have visions of rampant, uncontrollable plant, animal, or human diseases resulting from genetic engineering of microbes. While scientists believe the probability of such accidents is extremely low, biosafety regulations require them to take great precautions in testing genetically modified microorganisms in the natural environment. For this reason, commercial applications of microbial biotechnology to pest control in crops will necessarily be slow in coming.
Industrial applications of microbial biotechnology
The application of microbial biotechnology to industrial fermentation holds great promise for making crops more useful as renewable raw materials for manufacturing food, feed, fuel, fiber, and chemical feedstocks. Biotechnology makes it possible to use microorganisms, plant cells, animal cells, and cell-free systems of enzymes to make products.
These systems can be genetically and industrially engineered to produce virtually any organic product from virtually any organic raw material. Food engineer Munir Cheryan of the University of Illinois is using biological and ceramic membranes to separate desirable and undesirable end-products from fermentation mixtures without destroying the microorganisms or other biocatalysts, thus enabling an efficient, continuous process. Continuous process fermentation promises to make agricultural materials competitive with petroleum as raw materials for producing many products, including plastics.
Corn is one of the most common and useful raw materials for industrial fermentation. It is already used in very large quantities to produce ethanol for use as an additive to gasoline. The oxygenating effect of ethanol in gasoline reduces harmful emissions under some circumstances, increases octane, and reduces operating temperatures of air-cooled engines, thus reducing wear. The Clean Air Act of 1990 will substantially increase the demand for corn for fermentation. This, in turn, will increase the demand for fertilizer and pesticides. As other fermentation processes involving crops are perfected, there will be further increases in demand for crops.
Food scientist Hans Blaschek of the University of Illinois is employing biotechnology to perfect a process for making butanol from crop residue, processing waste, and/or corn. Butanol, currently made from petroleum, is an energy-dense alcohol that has potential as a fuel and a raw material for manufacturing synthetic rubber. It is already widely used as a chemical feedstock.
A number of animal biotechnology developments are underway that will affect feed requirements. Since corn and soybeans are primarily used for feed, the indirect effects on fertilizer and chemical use could be very important.
Scientists have known for decades that increasing somatotropin (growth hormone) levels in animals has many dramatic effects. Until recently, somatotropin could not be produced in large enough amounts to be important in commercial agriculture. Now, however, bovine (cattle) and porcine (pig) somatotropin can be produced in very large amounts using genetically modified microorganisms in fermentation processes.
When administered in small amounts daily, bovine somatotropin increases milk
production substantially, the greater increases being realized by less productive
animals. There is no change in hormone levels in milk from somatotropin-treated
animals. Feed efficiency in also increased.
When pigs receive supplemental amounts of porcine somatotropin, they produce more muscle and less fat. This may make pork more attractive to consumers who are trying to reduce their intake of animal fats. The feed efficiency of treated animals is increased from 10 to 40 percent, but the increase is not realized unless the protein content of the feed is substantially increased.
Two years ago, Cornell University scientists estimated that widespread use of porcine growth hormone in the U.S. would cause an increase in soybean acreage of 8 million acres, with a corresponding decrease in corn acreage o£ a similar amount. Working in the opposite direction is the trend toward supplementing swine rations with purified amino acids. These are made in industrial fermentation processes that use corn as raw material.
Other animal biotechnology efforts will change the fatty acid composition of meat toward less saturated fatty acids, thus addressing consumer concerns. There will be much more effective vaccines and pharmaceuticals. Reproductive efficiency will be enhanced. These changes will be especially important in developing countries, where animal production has been extremely inefficient. As is evident, some of the animal biotechnology developments would tend to reduce the demand for grain. In general, however, I think these developments will make animal products more desirable, useful, and affordable to the world's consumers and will increase the animal agriculture of the world substantially. This, in turn, would increase the demand for grain and for fertilizer and chemicals.
Even if biotechnology has benefits for agriculture, we do not know if Illinois fertilizer and chemical dealers will share in those benefits. We do know that there will be great competition for international agricultural markets. If Illinois farmers do not compete effectively in those markets, Illinois fertilizer and chemical dealers will not be successful either.
How can we assure that Illinois farmers will be the earliest and most effective adopters of new technology? Basic research will not provide this competitive edge. Basic research, though essential to agricultural improvement, is conducted-all over the world. Its results are rapidly disseminated around the World, providing proprietary advantage only to those who are first to translate the basic knowledge into practical knowledge and successful commercial products.
Developmental research, including biotechnology research, long touted as the key to U. S. agricultural competitiveness, will not provide the competitive edge. Much product-oriented developmental research is conducted or supported by international agribusiness firms. They are developing, manufacturing, and marketing the improved input products of agriculture all over the world. The farmers of other nations will have access to these improved products as soon or sooner than U. S. farmers.
The only way the U. S. can capture a proprietary benefit from its investments in basic research and biotechnology is to enlarge and improve its capacity for adaptive research and technology transfer, traditional roles of the universities and USDA Agricultural Research Service. It is only through these activities that alternative input products and practices are tested and compared, selected for their suitability in specific soil, environmental, and socioeconomic situations, and farmers are enabled to integrate appropriate products and practices into profitable, competitive enterprises.
Only if Illinois is more effective than competing states and nations in adaptive research and extension will its farmers gain a competitive edge in producing and marketing ,crops. Only if farmers gain this competitive edge will they be purchasing additional agricultural inputs. Only if Illinois is more effective than competitors in adaptive research and extension will the economic benefits of agricultural biotechnology reverberate through the food and agricultural infrastructure of Illinois.
Farmers and agribusiness people must work to assure that Illinois has the institutional capacity to conduct the adaptive research and extension required to make the state agriculturally competitive. If we fail to achieve technological leadership, the state's considerable public and private investment in biotechnology and other agricultural research will be lost. If we achieve technological leadership, we will realize a high return not only on our own investment in research and education, but also on sizeable investments in basic research and biotechnology around the world.
Agricultural biotechnology is the application of molecular biology and, especially, molecular genetics to solving agricultural problems and exploiting agricultural opportunities. Biotechnology research leads to new and improved agricultural inputs. Biotechnology is not a panacea. Ultimately, it will benefit agriculture by enabling a number of relatively small, incremental improvements in technology, just as agricultural research has in the past.
Biotechnology provides new opportunities to build pest- and stress-resistance into plants. Such developments may reduce the demand for pesticides. On the other hand, genetic engineering of crops for herbicide resistance may increase use of some broad-spectrum, environmentally-benign herbicides. Biotechnology research will produce crop varieties with special characteristics that increase their value as grain and forage. Growers can justify greater inputs of fertilizer and chemicals when producing higher value crops.
Biotechnology will change patterns of fertilizer use. The most profound changes will come about if and when major cereal crops are enabled to fix nitrogen. Closer at hand are biotechnology tools for screening crops for nutrient uptake efficiency, and nitrogen-fixing microorganisms that are more efficient and productive.
Microbial biotechnology, particularly as applied to industrial fermentation, will increase the demand for crops and crop residues as raw material for manufacturing food and non-food products. This, in turn, will increase the demand for fertilizer and chemicals. Likewise, biotechnology developments in animal agriculture are likely to increase the overall demand for animal products, thus increasing the need for feed and associated production inputs, including fertilizer and chemicals.
Illinois fertilizer and chemical dealers will not benefit from biotechnology unless Illinois farmers can use this important technology to gain a competitive edge in international agricultural markets. Illinois must enlarge and improve its institutional capacity for adaptive research and extension in order to capture the benefits of world-wide investment in biotechnology research.
