The Impact of Genetically Engineered Crops on Farm Sustainability in the United States Public Briefing NAS Lecture Room April 13, 2010

David E. Ervin (chair), Portland State University Yves Carrière, University of Arizona William J. Cox, Cornell University Jorge Fernandez-Cornejo, USDA-Economic Research Service Raymond A. Jussaume, Washington State University Michele C. Marra, North Carolina State University Micheal D.K. Owen, Iowa State University Peter H. Raven*, Missouri Botanical Garden L. LaReesa Wolfenbarger, University of Nebraska, Omaha David Zilberman, University of California, Berkeley *Members of the National Academy of Sciences Study Committee Members

Study the environmental, economic, and social impacts of genetically engineered (GE) crops on U.S. farms Identify gaps and future applications of genetic engineering technology Funded by the National Research Council Purpose of the Study Retrospective examination (1996-today) Geographically restricted to the United States Effects on farms with and without GE-crop production

Genetic Engineering Technology 3 Types of Resistance Herbicide Resistance (HR) –Most U.S. crops engineered with resistance to glyphosate Insect Resistance (IR) –Types of soil bacterium (Bacillus thuringiensis) introduced into plant to target susceptible insects Virus Resistance

Genetically Engineering Crops Nationwide acreage of GE soybean, corn, and cotton as a percentage of all acreage of these crops Source: USDA-NASS (2001, 2003, 2005, 2007, 2009b).

GE Crops Analyzed in the Report Soybeans –Herbicide resistance Corn –Herbicide resistance –Insect resistance Cotton –Herbicide resistance –Insect resistance

Environmental Effects Complementary adoption of HR crops and conservation tillage practices – Improves soil retention –Probable improvement in surface water quality – Infrastructure needed to track water quality effects Herbicide-Resistant Crops Trends in conservation tillage practices Source: CTIC, 2009; USDA-ERS, 2009.

Environmental Effects Glyphosate-Resistant Crops Substituted for more toxic herbicides Exclusive, repeated use reduced effectiveness of glyphosate for control of some weeds Expect further increases in weeds resistant to glyphosate if current practices continue Managing resistant weeds: a return to environmentally- harmful practices Development and implementation of efficient resistance management strategies needed if herbicide resistant crops are to remain an effective weed-management tool

Environmental Effects Insect-Resistant Crops If replacing broad-spectrum insecticides, then favorable effects for beneficial insects may occur No resistance of economic or agronomic consequence so far Greater use of IR crops with multiple toxins targeting pest should delay the evolution of resistance further

Gene Flow No or very limited spatial overlap between GE crops and potentially interbreeding relatives in the United States Future concerns depend on what GE crops emerge in market Primarily a concern to producers of non-GE varieties of these crops Environmental Effects

Adequate research has not been conducted on the social effects on GE crops Social impacts accompany technological developments Social Effects Social relationships affect technology development Structure of seed industry affects farmers’ options

Social Effects Share of planted acres on corn and soybean seeds by largest four firms (CR4) Source: Stiegert et al. (2009)

Areas in Need of Research Social Effects Non-Adopters - Livestock Producers - Organic Farmers Property Rights and Ethical Issues Farmer Conflict and Community Stability

Adopters have benefitted from: Cost-effective weed control Reduced losses from insect pests Reduced expenditures on pesticides and fuel Increased worker safety Greater flexibility in farm management Lower risk of yield variability Economic Effects

Economic effects on non-GE producers are mixed and poorly understood Purchasing decisions of GE producers affect non-GE producers No quantitative estimate of economic impact on livestock producers Landscape-level effects on pests Costs of inadvertent gene flow Benefits of segregated markets Economic Effects

Stakeholder group needed to document emerging weed-resistance problems and develop cost-effect practices to increase longevity of HR technology Infrastructure needed on the water quality effects of GE crops Public and private research institutions improve monitoring and assessment capacity to ensure GE technologies contribute to sustainable agriculture Increased support for the development of ‘public goods’ traits through collaborative approaches to genetic engineering technology Recommendations

Thank you. Report is available online at