!"# $" $!"#% $!"#% & '& !"#$ %& '( )*%+ ,-& . /0( )*%+ ,-&% . 12( 2!"34'56# !()**+++,-,.,&/ Ecological Effects of Pest Resistance Genes in Managed Ecosystems ACKNOWLEDGMENTS The Editors wish to acknowledge the members of the Workshop Steering Committee, whose judicious guidance helped define the objectives and methodology of the program, and who were instrumental in assembling a superb group of participants. Helen M. Alexander, University of Kansas Hector Quemada, Crop Technology Consulting, Inc. Joy Bergelson, University of Chicago Steven Radosevich, Oregon State University Greg Dwyer, University of Notre Dame Erin Rosskopf, USDA-ARS Dave Heron, USDA-APHIS-PPQ-SS Allison Snow, Ohio State University Peggy Lemaux, UC Berkeley Pat Traynor, ISB, Virginia Tech Donna H. Mitten, AgrEvo/PGS Jim Westwood, Virginia Tech Calvin O. Qualset, UC Davis James White, USDA-APHIS-PPQ-SS This workshop was sponsored by Information Systems for Biotechnology, a program funded at Virginia Tech by a grant from USDA’s Cooperative State Research, Education, and Extension Service. Additional support from USDA/APHIS and BIO is gratefully acknowledged. The complete text of this Proceedings is available on the ISB web site (http://www.isb.vt.edu). Print copies are available at no charge; send your request by email to [email protected] or by fax to 540-231-2614. Please be sure to include a complete mailing address. ii Ecological Effects of Pest Resistance Genes in Managed Ecosystems FOREWORD The idea for a highly focused, multi-disciplinary risk assessment workshop emerged from conversations with scientists, regulatory officials and members of public interest groups. Discussions about the environmental release of transgenic crops, either for field tests or for commercial use, seemed always to touch on what constitutes the basis for decisions, and how those decisions could be strengthened. In 1989, the National Research Council published Field Testing Genetically Modified Organisms; Framework for Decisions, the so-called Green Book. Ten years later, it’s worth taking a look at one of the issues surrounding the use of genetically engineered crops—the impact of introducing pest resistance into crops, and the potential for related species to benefit by acquiring the trait. Combining our collective experience with conventional crops and what we know about engineered varieties brought into focus what we know now, and helped identify the gaps in our knowledge. From this came recommendations for experimental approaches that would generate the needed data. Most participants found the multi-disciplinary science- based approach used in this workshop to be surprisingly effective in bridging gaps between participants from different disciplines, and in stimulating new ideas for research. This format could well serve as a model for similar evaluations of other risk issues associated with the commercial use of transgenic crops in the US and other countries. It is our hope that the reports in this volume will serve to support decision making at all levels and will stimulate greater interest in and funding for risk assessment research. iii Ecological Effects of Pest Resistance Genes in Managed Ecosystems iv Ecological Effects of Pest Resistance Genes in Managed Ecosystems TABLE OF CONTENTS ACKNOWLEDGMENTS............................................................................................................................ ii FOREWORD..............................................................................................................................................iii EXECUTIVE SUMMARY........................................................................................................................... 3 James H. Westwood and Patricia Traynor PLENARY PAPERS ................................................................................................................................13 The Concept of Familiarity and Pest Resistant Plants ........................................................................... 15 Karen Hokanson et al. Weed Management: Implications of Herbicide Resistant Crops........................................................... 21 Stephen O. Duke Escape of Pest Resistance Transgenes to Agricultural Weeds: Relevant Facets of Weed Ecology...... 27 Nicholas Jordan Mechanisms of Pest Resistance in Plants .............................................................................................. 33 Noel Keen Consequences of Classical Plant Breeding for Pest Resistance............................................................. 37 Donald N. Duvick Insect Limitation of Weedy Plants and Its Ecological Implications...................................................... 43 Svata M. Louda Pathogens and Plant Population Dynamics: The Effects of Resistance Genes on Numbers and Distribution ............................................................................................................................................ 49 Janis Antonovics Extrapolating from Field Experiments that Remove Herbivores to Population-Level Effects of Herbivore Resistance Transgenes.......................................................................................................... 57 Michelle Marvier and Peter Kareiva WORKING GROUP REPORTS.............................................................................................................. 65 Report of the Berry Working Group...................................................................................................... 67 Report of the Brassica Crops Working Group ...................................................................................... 73 Report of the Cucurbit Working Group................................................................................................. 79 Report of the Grains Working Group .................................................................................................... 89 Report of the Turfgrasses Working Group ............................................................................................ 97 Report of the Poplar Working Group................................................................................................... 105 Report of the Sunflower Working Group ............................................................................................ 113 PARTICIPANT LIST .............................................................................................................................. 119 OBSERVER LIST................................................................................................................................... 127 1 Ecological Effects of Pest Resistance Genes in Managed Ecosystems 2 Ecological Effects of Pest Resistance Genes in Managed Ecosystems 3 Ecological Effects of Pest Resistance Genes in Managed Ecosystems 4 Ecological Effects of Pest Resistance Genes in Managed Ecosystems EXECUTIVE SUMMARY James H. Westwood and Patricia Traynor Virginia Tech INTRODUCTION releasing such crops pose any special risk of creating or exacerbating a weed problem? Genetically engineered crops have become a visible part of the US agricultural landscape. The Assessing the potential for transgenic pest first transgenic varieties in or near commercial resistant crops to become problem weeds, or to production have been modified for a range of enhance the weediness of nearby sexually characteristics conferring improved agronomic compatible relatives, is a complex task. performance, herbicide tolerance, pest and Information is required from many disciplines – disease resistance, handling and storage weed science, agronomy, population biology and properties, as well as other traits. However the genetics, entomology, plant breeding, ecology, use of biotechnology to address constraints in plant pathology, molecular biology, and more. agricultural production brings with it questions Scientific evidence in support of informed risk regarding the potential of genetically modified assessment and decision making thus lies in the organisms (GMOs) to cause unacceptable collective knowledge of experts from these impacts on the environment. fields. Among the ecological issues associated with The workshop on Ecological Effects of Pest transgenic crops is the possibility that some Resistance Genes in Managed Ecosystems was newly introduced traits, such as pest or pathogen organized to promote multidisciplinary resistance, could confer added fitness to the crop. discussions that would lead to a synthesis of As a result, the crop may gain weedy what we already know, and what we don’t know, characteristics if its ability to survive and spread regarding the environmental impact of pest outside of cultivation is enhanced. A second resistant crops. In so doing, the workshop issue arises if such crops are grown in the provided an opportunity to reexamine a key issue vicinity of compatible wild or weedy related related to the responsible development and use of species; transfer of the trait by natural agricultural biotechnology products. hybridization may produce hybrid progeny that are more aggressive or more difficult to control. APPROACH These issues are no longer hypothetical, as at least seven groups of crops being engineered for The workshop focused on seven groups of crop pest resistance are known to have sexually species that have weedy relatives in North compatible wild or weedy relatives in the US. America: berries, certain grains