Isaac Ishaaya (Ed.)

Biochemical Sites of Insecticide Action and Resistance

Springer Berlin Heidelberg New York Barcelona Hong Kong London Mailand Paris Singapore Tokyo

Isaac Ishaaya (Ed.)

Biochemical Sites of Insecticide Action and Resistance

With 46 Figures

Springer

Professor Dr. ISAAC ISHAAYA Department of Entomology Agricultural Research Organization The Volcani Center Bet Dagan 50250 Isarael

ISBN-13: 978-3-642-64022-3 e-ISBN-13: 978-3-642-59549-3 DOl: 10.1007/978-3-642-59549-3

Library of Congress Cataloging-in-Publication Data

Biochemical sites of insecticide action and resistance I Isaac Ishaaya (ed.) p. cm.

Includes bibliographical references. ISBN-13: 978-3-642-64022-3 1. Insecticides - Mechanism of action. 2. Insecticide resistance. I. Ishaaya, I.

SB951.5 .B56 2000 632'.9517 - dc21 00-063580

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Preface

In recent years many of the conventional methods of insect control by broad­spectrum synthetic chemicals have come under scrutiny because of their unde­sirable effects on human health and the environment. In addition, some classes of pesticide chemistry, which generated resistance problems and severely affected the environment, are no longer used. It is against this background that the authors of this book present up-to-date findings- relating to biochemical sites that can serve as targets for developing insecticides with selective prop­erties, and as the basis for the elucidation of resistance mechanisms and countermeasures.

The book consists of eight chapters relating to biochemical targets for insec­ticide action and seven chapters relating to biochemical modes of resistance and countermeasures. The authors of the chapters are world leaders in pesti­cide chemistry, biochemical modes of action and mechanisms of resistance. Biochemical sites such as chitin formation, juvenile hormone and ecdysone receptors, acetylcholine and GABA receptors, ion channels, and neuropeptides are potential targets for insecticide action. The progress made in recent years in molecular biology (presented in depth in this volume) has led to the iden­tification of genes that confer mechanisms of resistance, such as increased detoxification, decreased penetration and insensitive target sites. A combina­tion of factors can lead to potentiation of the resistance level. Classifications of these mechanisms are termed gene amplification, changes in structural genes, and modification of gene expression.

This book is intended to serve as a text for researchers, university profes­sors and graduate students involved in developing new groups of insecticides suited to integrated pest management (IPM) and insecticide resistance man­agement (IRM) programs. The data presented are essential for the establish­ment of new technologies for developing compounds that will impact our future agricultural practices.

In the preparation of the manuscript, the editor and the authors are indebted to the reviewers of the various chapters for valuable suggestions and criticism: J.R. Bloomquist (USA), D. Dean (USA), L.M. Field (UK), K. van Frankenhuyzen (Canada), R.Y. Gunning (Australia), I. Ishaaya (Israel),A. Koch (USA), R. Laprade (Canada), H. Oberlander (USA), J.-L. Schwartz (Canada), J.G. Scott (USA), B.D. Siegfried (USA), S. Sohi (Canada), C.-N. Sun (Taiwan),

VI Preface

V. Vachon (Canada), P. Weintraub (Israel), H. Wieczorek (Germany), M.S. Williamson (UK), and M. Wolfersberger (USA).

I thank Mrs. Svetlana Kontsedalov for her patience in typing and organiz­ing the various sections. I am indebted to my wife Mrs. Eulalie Ishaaya-van Hoye for her support and assistance throughout the preparation of the book.

Isaac Ishaaya

Contents

Biochemical Processes Related to Insecticide Action: an Overview I. ISHAAYA

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 Chitin Synthesis Inhibition ............................... 2 3 Ecdysone and Juvenile Hormone Receptors . . . . . . . . . . . . . . . . . . 4 4 Acetylcholine Receptors .................................. 5 5 GABA and Glutamate Receptors and Ion ChaI1p.els ........... 6 6 Other Biochemical Sites ................................. 8 7 Conclusions .......................................... . 9 References ................................................... 10

GABA and Glutamate Receptors as Biochemical Sites for Insecticide Action J.R. BLOOMQUIST

1 Introduction ........................................... 17 2 GABA Receptors in Mammals and Insects .................. 18 2.1 Classification of GABA Receptors ............ . . . . . .. . . . . . . 18 2.2 Structure and Physiological Role of Insect GABA Receptors. .. . 18 2.3 Pharmacology of GABA Receptors ......................... 19 3 Summary of Effects of Convulsants and Avermectins

on the GABA Receptor................................... 19 3.1 Polychlorocyc1oalkanes and Related Norbornanes ............ 21 3.2 Picrodendrin and Silphinene Natural Products .............. 22 3.3 Fipronil and Fipronil Analogs ............................. 25 3.4 Trioxabicyc1ooctanes and Related Compounds ............... 27 3.5 New Avermectins and the Mammalian GABA Receptor . . . . . . . . 28 3.6 Altered GABA Receptors in Resistance . . . . . . . . . . . . . . . . . . . . . . 30 3.7 Resistance to New and Experimental Insecticides ............ 31 4 Glutamate-Gated Chloride Channels ....................... 33 4.1 Physiology, Pharmacology, and Molecular Structure .......... 33 4.2 Effects of the Avermectins ...................... . . . . . . . . . 34 4.3 New Avermectins and Their Uses .......................... 35 4.4 Target Site Resistance to the Avermectins ................... 36 5 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 References ................................................... 37

VIII Contents

Insecticides Affecting Voltage-Gated Ion Channels E. ZLOTKIN

Insecticides and Ion Channels ............................ 43 1.1 Scope and Aim ....... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 1.2 Voltage-Gated Ion Channels .............................. 44 2 Industrial Insecticides Targeting Ion Channels ............... 48 2.1 Insecticides of the Voltage-Gated Sodium Channels ........... 48 2.2 Insecticides of the Potassium and Calcium Channels .......... 52 3 The Functional Diversity of Insecticides .................... 54 3.1 Multiplicity of Effects ....................... . . . . . . . . . . . . 54 3.2 Distinction Between Mammals and Insects ................. 56 4 Neurotoxic Polypeptides ................................. 57 4.1 Animal Group Specificity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 4.2 Insect-Selective Neurotoxins Affecting the Vol~age-Gated

Sodium Channels .......................... . . . . . . . . . . . . 58 4.2.1 Scorpion Venom Toxins .................................. 58 4.2.2 Spider Venom Toxins .................................... 61 4.3 Insect-Selective Neurotoxins Affecting the Voltage-Gated

Calcium Channel. . . . . . . . . . . . . . . . . . . . . . . .... . . . . . . . . . . . . . 61 5 Recombinant Baculovirus Bioinsecticides ................... 62 6 Allosteric Coupling and Allosteric Antagonism .............. 64 References ................................................... 69

Acetylcholine Receptors as Sites for Developing Neonicotinoid Insecticides R. NAUEN, U. EBBINGHAUS-KINTSCHER, A. ELBERT, P. JESCHKE, and K. TIETJEN

Introduction ........................................... 77 2 Insect Nicotinic Acetylcholine Receptors .................... 80 2.1 Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 2.2 Diversity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 3 Compounds Acting on the Nicotinic Acetylcholine Receptor . . . . 83 3.1 Radioligand Binding Studies .............................. 83 3.2 Neonicotinoids ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 3.2.1 Imidacloprid and Related Structures ...................... 86 3.2.2 Mannich Adducts as Experimental Pro-Neonicotinoids ....... 91 4 Electrophysiological Considerations ....................... 92 4.1 Whole Cell Voltage Clamp of Native Neuron Preparations ..... 94 4.1.1 Correlation Between Electrophysiology and Radioligand

Binding Studies .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 4.2 Agonists vs. Antagonists . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98 4.3 Receptor Subtypes in Locusta migratoria ................... 99 References ................................................... 101

Ecdysteroid and Juvenile Hormone Receptors: Properties and Importance in Developing Novel Insecticides S.R. PALL! and A. RETNAKARAN

Contents IX

1 Introduction. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . 107 2 Ecdysteroids. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 2.1 Biology, Endocrinology and Molecular Biology .............. 108 2.2 Receptors and Other Target Sites .......................... 112 2.3 Non-Steroidal Ecdysone Analogs and Their Mode

of Action .............................................. 115 2.4 Receptor-Based Screening Assays .......................... 119 2.5 Future Directions ....................................... 120 3 Juvenile Hormone. . .. . .. ... .. .. . . .. . .. ... . . .. .. . .. .. . . .. 121 3.1 Biology, Endocrinology and Molecular Biology .............. 121 3.2 Receptors and Other Target Sites .......................... 122 3.3 JH Analogs and Their Modes of Action ... . . . . . . . . . . . . . . . .. 125 3.4 Receptor-Based Screening Assays ... . . . . . . . . . . . . . . . . . . . . . . 126 3.5 Future Directions ....................................... 126 References ................................................... 127

Imaginal Discs and Tissue Cultures as Targets for Insecticide Action H. OBERLANDER and G. SMAGGHE

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 133 2 Imaginal Discs as Targets of Insect Hormones in Vivo

and in Vitro ............................................ 133 3 Insecticide Action in Vitro: Juvenile Hormone Mimics ........ 136 4 Insecticide Action in Vitro: Chitin Synthesis Inhibitors .. . . . .. 137 4.1 Organ" Cultures ......................................... 137 4.2 Cell Lines .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 139 5 Insecticide Action in Vitro: Ecdysteroid Agonists ............. 139 5.1 Organ Cultures ......................................... 139 5.2 Cell Lines .... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 140 References ................................................... 145

Insect Neuropeptide Antagonists: a Novel Approach for Insect Control M. ALTSTEIN and C. GILON

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 151 2 Backbone Cyclic Neuropeptide-Based Antagonist (BBC-NBA)

Approach .............................................. 153 2.1 Determination of the Active Sequence in the Neuropeptide .... 153 2.2 Development of a Competitive Lead Antagonist .............. 154 2.3 Improvement of the Antagonistic Activity

by Conformational Constraint ............................ 155

X Contents

2.4 Backbone Cyclization: a Tool for Imposing Conformational Constraint on Peptides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 156

2.5 Cycloscan: Conformationally Constrained BBC Peptide Libraries ................ . . . . . . . . . . . . . . . . . . . . . .. 156

3 Pheromone Biosynthesis Activating Neuropeptide ............ 158 4 Implementation of the BBC-NBA Strategy to the Pyrokinin/PBAN

Fa.mily ................................................. 159 5 Conversion of Neuropeptide Antagonists

into Insecticide Prototypes ............................... 160 6 Concluding Remarks .................................... 161 References ................................................... 163

Ion Balance in the Lepidopteran Midgut and Insecticidal Action of Bacillus thuringiensis J.L. GRINGORTEN

1 Introduction ........................................... 167 2 Pathogenesis ........................................... 168 3 Dependence of Host and Pathogen on Midgut pH ............ 169 4 Midgut K+ and H+ Regulation ............................. 170 4.1 The K+ Pump........................................ ... 170 4.2 The 2K+/1ATP Model for Midgut Alkalization. . . . . .. . .. . . . . .. 171 4.3 The 1K+/lATP Model for Midgut Alkalization. . . . . . .. .. . . . . .. 173 4.4 Transmembrane and Transepithelial Ion Gradients . . . . . . . . . . .. 175 5 Disruption of Midgut Ion Homeostasis

by Bacillus thuringiensis ................................. 176 5.1 In Vivo Changes ........................................ 176 5.2 In Vitro Changes ....................................... 179 5.3 What is the Source of the Elevated Hemolymph K+? .......... 181 5.4 Larval Paralysis and Mortality Factors ..................... 182 5.5 o-Endotoxin Effects on K+-Dependent Uptake

of Amino Acids ......................................... 182 5.6 Correlating O-Endotoxin Effects on the Isolated Midgut

with Insecticidal Activity ................................. 185 6 Receptor Binding and Ion-Channel Formation ............... 186 6.1 Receptor Binding ....................................... 186 6.2 Ion-Channel Formation in Artificial Membranes

and BBMVs..... .... ........ ......... ................... 188 6.3 Insect Cell Lines as Proxies for Midgut Cells In Vivo ... . . . . .. 190 7 Membrane Insertion and Pore Formation ................... 192 8 Conclusions and Thoughts ............................... 196 References ................................................... 197

Evolution of Amplified Esterase Genes as a Mode of Insecticide Resistance In Aphids L.M. FIELD, R.L. BLACKMAN, and A.L. DEVONSHIRE

Contents XI

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209 2 Biochemistry of Esterase-Based Resistance in M. persicae ..... 210 3 Molecular Genetics of Esterase Overproduction ............. 210 3.1 Esterase Genes in Susceptible Aphids ...................... 211 3.2 Organization of Amplified Esterase Genes .................. 212 3.3 Cytogenetic Studies of Amplified Esterases ................. 213 4 Expression of Esterase Genes ............................. 215 5 Wider Implications. . . . .. . .. .. . . . .. . . . . . . ... . ... ... .. . . .. 216 References ................................................... 217

Insensitive Acetylcholinesterase as Sites for Resistance to Organophosphates and Carbamates in Insects: Insensitive Acetylcholinesterase Confers Resistance in Lepidoptera R.Y. GUNNING and G.D. MOORES

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221 2 Acetylcholinesterase as a Resistance Mechanism ............. 222 3 Insensitive AChE in Lepidopteran Species ................... 224 4 Insensitive AChE in H. punctigera ......................... 225 5 Forms of AChE in Lepidoptera . . . . . . . . . . . . . . . . . . . . . . . . . .. 226 6 Effects of Altered AChE on Acetylcholine Hydrolysis ... . . . . .. 229 7 Inhibition Ratios and Toxicity in Lepidoptera ............... 230 8 Cross Resistance Between Organophosphates

and Carbamates in Lepidoptera. . . . . . . . . . . . . . . . . . . . . . . . . . .. 231 9 Genetics of Resistance in Lepidoptera ...................... 231 10 Fitness of Resistance in Lepidoptera. . . . . . . . . . . . . . . . . . . . . . .. 232 11 Evolution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233 12 Control of Altered AChE in Lepidoptera .................... 233 13 Population Genetics and Monitoring ....................... 234 14 Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235 References ................................................... 236

Glutathione S-Transferases and Insect Resistance to Insecticides C.-N. SUN, H.-Y. HUANG,N.-T. Hu, and W.-Y. CHUNG

1 Introduction ........................................... 239 2 General Features of Glutathione S-Transferases (GSTs) ........ 239 2.1 Roles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 2.2 Biochemical and Physiological Characteristics ...... . . . . . . .. 240 2.3 Structure, Regulation, and Evolution of GST Genes .......... 241 3 Insect GSTs ............................................ 242

XII Contents

3.1 Roles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 242 3.2 Biochemical and Physiological Characteristics ............... 243 3.3 GSTs and Insecticide Resistance ........................... 244 3.4 Molecular Biology Studies ................................ 245 4 GST Studies of Several Insects ............................ 246 4.1 Drosophila melanogaster ................................. 246 4.2 Musca domestica ....................................... 246 4.3 Anopheles gambiae ...................................... 247 4.4 Plutella xylostella ....................................... 248 5 Concluding Remarks .................................... 251 References ................................................... 252

Cytochrome P450 Monooxygenases and Insecticide Resistance: Lessons from CYP6D 1

J.G. SCOTT

1 Cytochrome P450 Monooxygenases ........................ 255 2 Insecticide Resistance ................................... 256 3 Monooxygenase-Mediated Insecticide Resistance ............ 256 4 CYP6Dl and Insecticide Resistance ........................ 257 5 Summary of the Lessons Learned from CYP6Dl ............. 261 References ................................................... 263

Mechanisms of Organophosphate Resistance in Insects B.D. SIEGFRIED and M.E. SCHARF

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 269 2 Physiological Mechanisms of Resistance .................... 270 2.1 Resistance Mechanisms Involving Enhanced

Biotransformation .............. ;....................... 272 2.1.1 Cytochrome-P450-Dependent Monooxygenases .............. 272 2.1.2 Glutathione S-Transferases ............................... 274 2.1.3 Hydrolytic Enzymes ............ , . . . . . . . . . . . .. . ... . . . .. .. 276 2.1.3.1 Quantitative Changes (Gene Amplification) ................. 277 2.1.3.2 Qualitative Changes ..................................... 281 2.2 Target Site Insensitivity .................................. 283 2.3 Interactions Between Resistance Mechanisms ............... 284 3 Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 286 References ................................................... 287

Contents XIII

Insect Midgut as a Site for Insecticide Detoxification and Resistance G. SMAGGHE and L. TIRRY

1 Introduction ........................................... 293 2 The Insect Gut: a Natural Digestive-Absorption

Architecture ........................................... 294 3 Enzymatic Metabolism of Pesticide Involved

in "Resistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 298 4 Impact of Ingestion, and Penetration and Disposition

in the Insect Body on Resistance to Pesticides . . . . . . . . . . . . . . .. 304 5 Attempts for Chemical Modeling of Digestion and Absorption

in Insect Midgut ........................................ 310 6 In Vitro Gut Cultures for Insecticidal Activity Studies ......... 314 References ................................................... 316

Impact of Insecticide Resistance Mechanisms on Management Strategies A.R. HOROWITZ and I. DENHOLM

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323 2 Overview of Resistance Mechanisms . . . . . . . . . . . . . . . . . . . . .. 324 3 Overview of Resistance Management Tactics ................ 325 4 Diagnosing Resistance ................................... 327 4.1 In Vitro Assays for Diagnosing Resistance .................. 328 5 Overpowering Resistance Mechanisms ..................... 331 6 Resolving and Exploiting Cross-Resistance ................. 332 7 Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 334 References ................................................... 335

Subject Index ................................................. 339

Contributors

M. ALTSTEIN (e-mail: vinnie2@netvision.net.il) Department of Entomology, The Volcani Center, ARO, Bet Dagan, 50250 Israel

R.L. BLACKMAN (e-mail: r.blackman@nhm.ac.uk) Natural History Museum, Cromwell Road, London, SW7 5BD, UK

J.R. BLOOMQUIST (e-mail: jbquist@vt.edu) Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA

W.-Y. CHUNG (e-mail: cnsun@hotmail.com) Department of Entomology, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China

I. DENHOLM (e-mail: ian.denholm@bbsrc.ac.uk) Department of Biological and Ecological Chemistry,IACR-Rothamsted, Harpenden, Herts AL5 2JQ, UK

A.L. DEVONSHIRE (e-mail: alan.devonshire@bbsrc.ac.uk) IACR-Rothamsted, Harpenden, Herts AL5 2JQ, UK

U. EBBINGHAUS-KINTSCHER (e-mail: ulrich.ebbinghaus-kintscher.ue@bayer-ag.de) Bayer AG, Agrochemicals Division, Research Insecticides, 51368 Leverkusen, Germany

A. ELBERT (e-mail: alfred.elbert.ae@bayer-ag.de) Bayer AG, Agrochemicals Division, Research Insecticides, 51368 Leverkusen, Germany

L.M. FIELD (e-mail: lin.field@bbsrc.ac.uk) IACR-Rothamsted, Harpenden, Herts AL5 2JQ, UK

XVI Contributors

C. GILON (e-mail: gilon@vms.huji.ac.il) Institute of Organic Chemistry, The Hebrew University, 91904 Jerusalem, Israel

J.L. GRINGORTEN (e-mail: 19ringo@nrcan.gc.ca) Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen Street East, Sault Ste. Marie, Ontario P6A 5M7, Canada

R.Y. GUNNING (e-mail: rgunning@enternet.com.au) NSW Agriculture, Tamworth Centre for Crop Improvement, RMB 944 Calala Lane, Tamworth, NSW, Australia 2340

A.R. HOROWITZ (e-mail: hrami@netvision.net.il) Department of Entomology, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel

N.-T. Hu (e-mail: nthu@dragon.nchu.edu.tw) Graduate Institute of Biochemistry, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China

H.-Y. HUANG (e-mail: cnsun@hotmail.com) Department of Entomology, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China

I. ISHAAYA (e-mail: vpisha@netvision.net.il) Department of Entomology, Agricultural Research Organization, The Volcani Center, Bet Dagan 50250, Israel

P. JESCHKE (e-mail: peter.jeschke.pj@bayer-ag.de) Bayer AG, Agrochemicals Division, Research Insecticides, 51368 Leverkusen, Germany

G.D. MOORES (e-mail: graham.moores@bbsrc.ac.uk) Department of Biological and Ecological Chemistry, IACR-Rothamsted, Harpenden, Herts AL5 2JQ, UK

R. NAUEN (e-mail: ralf.nauen.rn@bayer-ag.de) Bayer AG, Agrochemicals Division, Research Insecticides, 51368 Leverkusen, Germany

H. OBERLANDER (e-mail: hoberlander@gainesville.usda.ufl..edu) Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, U.S. Department of Agriculture, P.O. Box 14565, Gainesville, FL 32604, USA

Contributors XVII

S.R. PALLI (e-mail: rahsub@rohmhaas.com) Rohm and Haas Research Laboratories, 727 Norristown Road, Spring House, PA 19477, USA

A. RETNAKARAN (e-mail: aretnak@nrcan.gc.ca) Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen Street East, Sawt Ste. Marie, Ontario, Canada P6A 5M7

M.E. SCHARF (e-mail: mscharfl@unl.edu) Department of Entomology, 202 Plant Industry Building, University of Nebraska, Lincoln, NE 68583-0816, USA

J.G. SCOTT (e-mail: Jgs@cornell.edu) Department of Entomology, Comstock Hall, Cornell University, Ithaca, NY 14853-0901, USA

B.D. SIEGFRIED (e-mail: bsiegfried1@unl.edu) Department of Entomology, 202 Plant Industry Building, University of Nebraska, Lincoln, NE 68583-0816, USA

G. SMAGGHE (e-mail: guy.smagghe@rug.ac.be) Laboratory of Agrozoology, Faculty of Agricultural and Applied Biological Sciences, Ghent University, Coupure Links 563, 9000 Ghent, Belgium

C.-N. SUN (e-mail: cnsun@hotmail.com) Department of Entomology, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China

K. TIETJEN (e-mail: klaus.tietjen.kt@bayer-ag.de) Bayer AG, Agrochemicals Division, Research Insecticides, 51368 Leverkusen, Germany

1. TIRRY (e-mail: luc.tirry@rug.ac.be) Laboratory of Agrozoology, Faculty of Agricultural and Applied Biological Sciences, Ghent University, Coupure Links 653, 9000 Ghent, Belgium

E. ZLOTKIN (e-mail: zlotkin@vms.huji.ac.il) Department of Cell and Animal Biology, Institute of Life Sciences, The Hebrew University, 91904 Jerusalem, Israel