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Plant Pathology's Role in Anti-Crop Bioterrorism and Food Security


Abstracts of the 1999 APS Annual Meeting symposium:
Tuesday, August 10, 1999. Montreal, Quebec

Bioterrorism and agriculture. T. W. FRAZIER. GenCon, Montross, VA. Publication no. P-1999- 0143-SSA.

Until recently, the US government had not considered the national agriculture and food supply system as a critical national infrastructure. Now that this omission has been officially corrected, building a framework for defending this sector from various terrorist and biowarfare attacks is under federal consideration. Vulnerability of our animal herds and crops is a sectoral concern that needs to be addressed by government in close consultation with different agricultural and food association entities, companies, and academic institutions. Some useful guidance is available from intelligence, defense and law enforcement organizations. Other guidance is available from inspections and regulatory agencies concerned with food and product safety, and inspections for prohibited products, plants and animals. Combining knowledge about naturally occurring plant diseases with knowledge on known biowarfare agents, the agricultural plant research community should be able to provide important continuing assistance for helping structure a science-based national agricultural sectoral defense plan.
A historical perspective of bioterrorism and its implications for North American agriculture. W. A. DEEN. Private Consultant, Richmond, Missouri. Publication no. P-1999-0144-SSA.

Biological terrorism has existed since the beginning of recorded history. Most memorable events involve attacks directly against humans. History also documents attacks or alleged attacks against plant and animal agriculture. Current trends in North American agriculture may increase our vulnerability to this age- old terrorist weapon.
What is an effective pathogen? N. W. SCHAAD. USDA Foreign Disease - Weed Science Research Unit, Fort Detrick, MD. Publication no. P-1999-0145-SSA.

New and emerging diseases have been on the increase recently. Such diseases as bacterial canker of citrus, high plains virus of corn, sorghum ergot, Karnal bunt of wheat, and scab of wheat are a few examples. Is this increase due to natural causes such as an increase in air travel or international trade, or do deliberate introductions play a role? If we are to prevent deliberate introductions of crop pathogens, we first must be able to predict with high accuracy what the organism of choice might be. If asked to list their top ten pathogens, most plant pathologists would list pathogens they have worked with. Pathogens which historically cause severe losses would be high on most lists. However, instead of developing a list based on biases and personal experiences, I suggest use of a numerical rating system. To illustrate my proposed Effective Pathogen Index (EPI) rating system, the names of three highly effective pathogens will be solicited during the presentation. The pathogens will then be subjected to the rating system, and PI score developed for each organism.
Biological terrorism: Identifying and protecting our infrastructure. D. L. HUXSOLL. Louisiana State University, Baton Rouge, LA. Publication no. P-1999-0146-SSA.

Biological warfare is defined as the deliberate use of microorganisms or toxins derived from living organisms to induce death or disease in humans, animals or plants. Until recently the U.S. has been rather complacent about the bioterrorism threat. It is quite likely that terrorist use of weapons of mass destruction against the United States will become a true reality. Targets such as livestock, crops, tourism and transportation are likely terrorist choices in the future. Even small outbreaks of exotic disease in livestock or crops could remove the U.S. from the world market which it enjoys for its agricultural products. Critical to response in the event of a biological attack is the rapid identification of the etiologic agent or agents. The causative agent may be microbes and toxins that are not normally encountered in conventional labs. This may make the process of their identification slower and more difficult because of the requirements for reagents, equipment and specially trained personnel. Nevertheless, a rapid and reliable identification would be necessary in view of the critical management decisions that must follow. Numerous measures can be taken to reduce the human and economic impact.
Ground surveillance. R. L. FORSTER. University of Idaho Research and Extension Center, Kimberly, ID. Publication no. P-1999-0147-SSA.

New, or newly detected, plant diseases are reported regularly in scientific literature. The lag time between initial disease development and reporting may be months to years, depending on various factors. There is no requirement in the U.S. for reporting plant diseases as there is for human diseases; thus some serious plant diseases may go unreported. Satellite imagery is becoming increasingly sophisticated and the potential exists for the detection of plant diseases by this means, but at present, ground surveillance is required to identify the particular disease(s) responsible for the damage. Molecular as well as traditional diagnostic techniques are used routinely in many cases. Staffing in government and at colleges of agriculture in the U.S. has been reduced significantly due to budget constraints, and positions with extension or applied research responsibilities have been deemphasized. The U.S. is vulnerable to acts of bioterrorism due in part to a declining number of plant pathologists who can identify agents of plant disease. Greater emphasis on disease identification and a formal procedure for surveying and reporting serious new plant diseases in the U.S. would help to minimize their destructive effects.
Epidemiology and risk prediction. L. V. MADDEN (1) and H. Scherm (2). (1) Ohio State University, Wooster, OH 44691; (2) University of Georgia, Athens, GA 30602. Publication no. P-1999- 0148-SSA.

The risk of bioterrorism for plant diseases can be assessed through general probabilistic models. A simple but useful model for risk can be written of the form: I*E*S*(1-C), in which I is the probability of introduction of a pathogen, E is the probability of initial establishment (primarily dependent on the environment), S is the probability of disease spread, and C is the probability of successful confinement, eradication or control. With bioterrorisim, I can be considered equal to 1, since we are, by definition, dealing with deliberate introduction of pathogens. The other terms can vary greatly, however, based on the properties of the pathogen and host. E can be determined using the ecoclimate index method of Sutherst and Maywald or similar macro-environmental model, and S can be determined with the basic reproductive number (Ro) for epidemic development (i.e., the number of new infections arising from each initial infection). Using this risk-model approach, the potential for bioterrorism with plant pathogens will be explored under various scenarios.
Assuring food security: Detecting and controlling modified pathogens. J. E. LEACH. Kansas State University, Manhattan, KS. Publication no. P-1999-0149-SSA.

Throughout human history, examples exist where the introduction of exotic plant pathogens has caused catastrophic crop losses and tremendous suffering. Most of these examples are unintentional introductions. Intentional introductions can similarly incapacitate a nation's agricultural base by reducing the production of essential foods and negatively impacting the economy, e.g., through embargo of exports. What strategies are in place to minimize these potential threats to our food supplies? Two strategies, both components of currently employed crop protection strategies, are proposed. The first is 'responsive'. Early, rapid and accurate detection and identification of the pathogens are key to disease control. Determination of the pathogen's likely geographic origin may provide clues as to its baseline aggressiveness or virulence spectra. The second strategy is 'preventive'. Understanding the structure, function and evolution of genes involved in pathogenesis and virulence can focus attention to possible sites of intentional manipulation. Proactive development of crops with novel and broad spectrum resistances may hinder success of altered organisms.
Subtle forms of strategic indirect warfare: Infecting "soft" biological targets; some psychological, economic, and cultural consequences. R. HICKSON. USAF Academy, Boulder, CO. Publication no. P- 1999-0150-SSA.

By understanding the ways and means of strategic (and grand-strategic), indirect warfare, in the longer light of military history and intentionally ambiguous cultural subversions, we may better anticipate and strategically counteract inchoate, but subtly developing, forms of bio-terrorism, and longer-range forms of psycho-biological warfare, which may also be intensely dislocating new manifestations of economic warfare. By indirectly attacking and infecting unprotected "soft targest" such as seeds, a strategic aggressor or trans-national criminal syndicate or terrorist could have many disproportionately adverse effects upon a whole culture and its way of life. This may be but one new form of "asymmetrical warfare" against sophisticated (and decadent) interdependent societies. The developments from research in molecular biology and its variety of manipulative applications in bio-technologies give many new capabilities to the malevolent. We must therefore consider how there is now developing even a genetics- based "revolution in military affair (an RMA)" or "military-technical revolution," both of which could be strategically and indirectly employed, also combining "cybernetics" and "biological organisms" as instrumentalities of conflict - new "cyborganizations" as some strangely call this troublesome phenomenon.
Scientific investigation of bioterrorism: FBI Laboratory viewpoint. D. E. WILSON and R. S. Murch. FBI Laboratory, Washington, DC. Publication no. P-1999-0151-SSA.

Recently, much public attention has been given to the potential impact of hazardous materials to effect criminal or terrorist goals and objectives. The FBI is the lead Federal agency for response to events involving the threatened or actual illicit use of biological, chemical, radiological and nuclear materials, so- called "weapons of mass destruction." The FBI is responsible for leading crisis resolution and as investigating incidents through to prosecution. Science, technology and medicine necessarily play a critical role in the successful response and resolution of such events. The FBI Laboratory is evolving applications and research programs which focus on the detection, identification, analysis, handling, transport and storage of hazardous materials and related physical evidence. These purposefully complement the efforts of other key Federal scientific and medical agencies. Although various Federal, state and local programs began only considering humans and their environments, animal and plant agriculture are being realized as important economic and political targets of bioterrorism. Current and future issues and directions will be presented.

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