TESTIMONY
before the
COMMITTEE ON AGRICULTURE NUTRITION AND FORESTRY
UNITED STATES SENATE
THE HONORABLE RICHARD LUGAR, CHAIRMAN
Regarding
DEVELOPMENT OF BIOTECHNOLOGY AND ITS POTENTIAL APPLICATIONS IN THE AGRICULTURE AND FOOD SECTORS
Submitted by
Ray A. Bressan, Ph.D.
Professor of Plant Molecular Biology
Purdue University
West Lafayette, Indiana
October 6, 1999
Thank you, Mr. Chairman, for the invitation to appear before the committee. My name is Ray Bressan. I am Professor of Plant Molecular Biology at Purdue University in West Lafayette Indiana. My primary area of research for the past 24 years has been the effects of environmental stresses on plants.
Stresses such as drought, salinity, and temperature extremes impose a significant limitation on the genetic potential of crops. Cumulatively, these factors are responsible for a 70% average reduction in the potential productivity of agriculture. Thus overcoming these stresses represents an enormous opportunity for not only increased crop performance but also for stabilized yields, helping to free farmers from the uncertainty of the weather. Even the home gardener and organic farmer could appreciate that.
If crop yields become more independent of fluctuating climate, we can eventually be relieved from a fear and constraint that has plagued human civilization from the dawn of agriculture when the first ground was broken and seeds were planted. As I am sure you know, this fear of catastrophic crop failure caused by unfavorable weather has become reality often enough.
For instance, from the beginning of recorded history we know of drought- and pest- plagued crops deeply troubling ancient pharaohs. Need we be reminded of the tragic famine in China in the 1950's, in Somalia in the last decade and most recently, famine in North Korea. These tragic famines serve as warnings to us that a modern day weather-related crop disaster could even threaten world food supplies. What helping hand will be there if prolonged serious drought strikes a major part of the world like North America or Europe? Short of catastrophe, even localized droughts such as experienced in the Eastern United States this summer are disturbing enough. Instead of pretending that a catastrophic crop failure simply cannot happen, should we not be as prepared as possible? New and exciting advances in agricultural biotechnology are affording us the opportunity to be prepared.
Scientists have long known of many wild plants with innate tolerance to these important environmental stresses. However, the introduction of these wild plants into agriculture faces insurmountable economic, political and cultural barriers. The list of plants used in agriculture is shrinking, not expanding. Today, amazingly over 50% of world-wide food production is obtained from only four plant species, and almost 95% of food grown on our planet comes from only 30 different plants. With this narrow diversity of food crops that are all susceptible to weather-related stress, an important goal for modern agricultural research needs to be the genetic modification of major crop species for stress tolerance. Use of traditional breeding practices for stress-related research has so far achieved very limited success. This is largely because: first, tolerance to drought, temperature and salinity and other abiotic stresses is genetically complex and difficult to manipulate by conventional breeding methods. Second, introduction by classical breeding of tolerance genes from drought or other stress tolerant wild plants also introduces many undesirable genes including those controlling traits such as poor palatability, poor processing or storage properties and even the presence of dangerous toxins. Crop genetic engineering is attractive because the loss of desirable agronomic traits can be avoided since only a very limited and controlled number of genes are introduced into the target crop in each gene transfer event. Our biggest problem so far has not been one of engineering technology but rather the lack of a clear concept about the elements and mechanisms by which plants accomplish tolerance, and thereby a lack of good genes through which tolerance might be achieved. Yet, in the last decade, research using biotechnology has demonstrated our ability to genetically engineer plants for drought, cold and other abiotic stress tolerance. In fact, using genetic engineering, scientists from here and abroad have transferred twenty different genes that impact tolerance to recipient sensitive model plants. Even so, the level of tolerance achieved in any of these experiments so far has not been sufficient for use by farmers. These achievements have been informative, however. For instance, we have been surprised to learn that stress in plants, like in humans, accelerates the aging process. Now, there is reason to be optimistic that future crops can be engineered with much greater resistance to drought and other stresses.
You may be aware that many fields of biology are presently entering a truly new era in which established knowledge is being re-examined. The field of abiotic stress biology is no exception. Substantial renewed interest in genetic engineering for enhanced tolerance to drought, and other complex traits in plants is thus being generated. We are progressing from describing only the individual elements of complex biological processes to an approach where systems analysis and engineering are possible. The concepts and technologies underlying the terms genomics and bioinformatics, which are often used to describe these new approaches in biology, will, I believe, finally allow us to make major impacts on complex genetic characteristics such as drought-tolerance. To put it simply, we no longer have to think in terms of the partial impact of this gene or that gene on drought tolerance, but we will be able to consider all of the genes involved. This is becoming possible only because of the shift in scale of research and thinking brought about originally by the human genome sequencing project and recently the Arabidopsis genome sequencing and other plant genomics projects. Plant scientists are acutely aware and grateful of the Senate's historic generous support for our plant genomics efforts. We envisage a many fold return from this investment in the form of increased expansion and competitiveness of our agricultural economy. I believe that we will in the near future engineer plants tolerant to much more salinity than they can withstand now. These modified plants will have such enhanced salt-tolerance that farmers will be able to irrigate them with mixed solutions of sea and fresh water. This would have very positive implications for farms in states and nations bordering oceans and the Gulf of Mexico.
Let me now also remind everyone that working on drought- or salt-tolerance has often been interpreted or perceived as preparing for growing crops in true deserts, but this seems futile and it is not a realistic goal of researchers in this field. It is difficult to imagine how productive agriculture could work where water is absent or is prohibitively costly to obtain. Instead, the goal of scientists working on genetic engineering of drought tolerance is to increase or stabilize productivity of crops in areas that are already being farmed.
This is important because the goal of agricultural biotechnology research
in general is not to expand agriculture into wilderness areas, or into any undeveloped ecosystem, but exactly the opposite. We want to develop crops that allow us to more effectively utilize land that is already committed to agriculture, and thereby avoid expansion and further destruction of other ecosystems. In fact, I believe that most plant scientists have a vision and expectation that this new technology will be crucial to the preservation of our planet's diverse ecosystems. Let us keep in mind that the pressing need for agricultural expansion that has been created by an ever-expanding human population has already destroyed vast amounts of natural ecosystems. We as both scientists and citizens want less of this destruction, not more.
We advocate the use of agricultural biotechnology from the perspective of concerned citizens alarmed at the increasing environmental impact of our expanding population and as informed knowledgeable scientists that understand the valuable help this technology offers. Without the gains in crop productivity made in the last 30 years, we would have needed to plow under much of the now remaining natural ecosystems suitable for agriculture. The benefits that this new technology offers to the preservation of wildlands is often lost to the critics of biotechnology. For these and many more reasons, it is clear that continued and even expanded public acceptance and support for these exciting and promising technologies is certainly in the best interest of all who share an interest in the mutual well-being of ourselves and our planet. We appreciate the leadership demonstrated by the chairman and the committee in advancing these life sustaining and environment protecting technologies.