Modern Methods in Crop Protection Research

This handbook and ready reference highlights a couple of basic aspects of recently developed new methods in modern crop protection research, authored by renowned experts from major agrochemical companies. Organized into four major parts that trace the key phases of the compound development process, the first section addresses compound design, while the second covers newly developed methods for the identification of the mode of action of agrochemical compounds. The third part describes methods used in improving the bioavailability of compounds, and the final section looks at modern methods for risk assessment. As a result, the agrochemical developer will find here a valuable toolbox of advanced methods, complete with first-hand practical advice and copious examples from current industrial practice.

PREFACE

PART I: Methods for the Design and Optimization of New Active Ingredients

HIGH-THROUGHPUT SCREENING IN AGROCHEMICAL RESEARCH
Introduction
Target-Based High-Throughput Screening
Other Screening Approaches
In Vivo High-Throughput Screening
Conclusions

COMPUTATIONAL APPROACHES IN AGRICULTURAL RESEARCH
Introduction
Research Strategies
Ligand-Based Approaches
Structure-Based Approaches
Estimation of Adverse Effects
In-Silico Toxicology
Programs and Databases
Conclusion

QUANTUM CHEMICAL METHODS IN THE DESIGN OF AGROCHEMICALS
Introduction
Computational Quantum Chemistry: Basics, Challenges, and New Developments
Minimum Energy Structures and Potential Energy Surfaces
Physico-Chemical Properties
Quantitative Structure-Activity Relationships
Outlook

THE UNIQUE ROLE OF HALOGEN SUBSTITUENTS IN THE DESIGN OF MODERN CROP PROTECTION COMPOUNDS
Introduction
The Halogen Substituent Effect
Insecticides and Acaricides Containing Halogens
Fungicides Containing Halogens
Plant Growth Regulators (PGRs) Containing Halogens
Herbicides Containing Halogens
Summary and Outlook

PART II: New Methods to Identify the Mode of Action of Active Ingredients

RNA INTERFERENCE (RNAI) FOR FUNCTIONAL GENOMICS STUDIES AND AS A TOOL FOR CROP PROTECTION
Introduction
RNA Silencing Pathways
RNAi as a Tool for Functional Genomics in Plants
RNAi as a Tool for Engineering Resistance against Fungi and Oomycetes
RNAi as a Tool for Engineering Insect Resistance
RNAi as a Tool for Engineering Nematodes Resistance
RNAi as a Tool for Engineering Virus Resistance
RNAi as a Tool for Engineering Bacteria Resistance
RNAi as a Tool for Engineering Parasitic Weed Resistance
RNAi Safety in Crop Plants
Summary and Outlook

FAST IDENTIFICATION OF THE MODE OF ACTION OF HERBICIDES BY DNA CHIPS
Introduction
Gene Expression Profiling: A Method to Measure Changes of the Complete Transcriptome
Classification of the Mode of Action of an Herbicide
Identification of Prodrugs by Gene Expression Profiling
Analyzing the Affected Metabolic Pathways
Gene Expression Profiling: Part of a Toolbox for Mode of Action Determination

MODERN APPROACHES FOR ELUCIDATING THE MODE OF ACTION OF NEUROMUSCULAR INSECTICIDES
Introduction
Biochemical and Electrophysiological Approaches
Fluorescence-Based Approaches for Mode of Action Elucidation
Genomic Approaches for Target Site Elucidation
Conclusion

NEW TARGETS FOR FUNGICIDES
Introduction: Current Fungicide Targets
A Retrospective Look at the Discovery of Targets for Fungicides
New Sources for New Fungicide Targets in the Future?
Methods to Identify a Novel Target for a Given Compound
Methods of Identifying Novel Targets without Pre-Existing Inhibitors
Non-Protein Targets
Resistance Inducers
Beneficial Side Effects of Commercial Fungicides
Concluding Remarks

PART III: New Methods to Improve the Bioavailability of Active Ingredients

NEW FORMULATION DEVELOPMENTS
Introduction
Drivers for Formulation Type Decisions
Description of Formulation Types, Their Properties, and Problems during Development
Bioavailability Optimization
Conclusions and Outlook

POLYMORPHISM AND THE ORGANIC SOLID STATE: INFLUENCE ON THE OPTIMIZATION OF AGROCHEMICALS
Introduction
Theoretical Principles of Polymorphism
Analytical Characterization of Polymorphs
Patentability of Polymorphs
Summary and Outlook

THE DETERMINATION OF ABRAHAM DESCRIPTORS AND THEIR APPLICATION TO CROP PROTECTION RESEARCH
Introduction
Definition of Abraham Descriptors
Determination of Abraham Descriptors: General Approach
Determination of Abraham Descriptors: Physical Properties
Determination of Abraham Descriptors: Examples
Application of Abraham Descriptors: Descriptor Profiles
Application of Abraham Descriptors: LFER Analysis
Application of Abraham Descriptors: Generality of Approach

PART IV: Modern Methods for Risk Assessment

ECOLOGICAL MODELING IN PESTICIDE RISK ASSESSMENT: CHANCES AND CHALLENGES
Introduction
Ecological Models in the Regulatory Environment
An Overview of Model Approaches
Regulatory Challenges

THE USE OF METABOLOMICS IN VIVO FOR THE DEVELOPMENT OF AGROCHEMICAL PRODUCTS
Introduction to Metabolomics
MetaMap¿Tox Data Base
Evaluation of Metabolome Data
Use of Metabolome Data for Development of Agrochemicals
Discussion
Concluding Remarks

SAFETY EVALUATION OF NEW PESTICIDE ACTIVE INGREDIENTS: ENQUIRY-LED APPROACH TO DATA GENERATION
Background
What Is the Purpose of Mammalian Toxicity Studies?
Addressing the Knowledge Needs of Risk Assessors
Opportunities for Generating Data of Direct Relevance to Human Health Risk Assessment within the Existing Testing Paradigm
Enquiry-Led Data Generation Strategies
Conclusions

ENDOCRINE DISRUPTION: DEFINITION AND SCREENING ASPECTS IN THE LIGHT OF THE EUROPEAN CROP PROTECTION LAW
Introduction
Endocrine Disruption: Definitions
Current Regulatory Situation in the EU
US EPA Endocrine Disruptor Screening Program and OECD Conceptual Framework for the Testing and Assessment of Endocrine-Disrupting Chemicals
ECETOC Approach
Methods to Assess Endocrine Modes of Action and Endocrine-Related Adverse Effects in Screening and Regulatory Contexts
Proposal for Decision Criteria for EDCs: Regulatory Agencies

INDEX

Peter Jeschke gained his PhD in organic chemistry at the University of Halle/Wittenberg (Germany), after which he moved to Fahlberg-List Company (Germany) to pursue agrochemical research before going to the Institute of Neurobiology and Brain Research, German Academy of Sciences. In 1989 he joined Bayer as lab leader in animal health research and eight years later he took a position at the Bayer Crop Protection Business Group, where he is currently Head of Research Pest Control Chemistry 2. Since 2011, he is honorary professor at the University of Dusseldorf (Germany). Prof. Dr. Jeschke has more than 180 patent applications and scientific publications to his name.


Wolfgang Kramer gained his PhD in organic chemistry from the TU Stuttgart (Germany) in 1968, after which he joined the Institute of Textile Chemistry at Stuttgart University, before moving to Bayer Plant Protection as lab leader in plant protection research in 1970. Between 1984 and 1990 he was Head of Global Chemistry Fungicides, and Head of Insecticide Chemistry thereafter. Retired since 2005, Dr. Kramer has over 250 patent applications and publications to his name.

Ulrich Schirmer received his PhD in organic chemistry from Stuttgart University (Germany) in 1973, and worked subsequently postdoctoral as a researcher at Paris-Orsay (France). He joined BASF in 1974, eventually becoming Senior Vice President responsible for plant protection research for chemical synthesis, process development and biological R&D. Since 2003, he has been working as a freelance consultant to start-ups in the fields of biotechnology, chemistry and agriculture. Dr. Schirmer is author and co-author of more than 100 patent applications and scientific publications.


Matthias Witschel received his PhD in organic chemistry in 1994 at the University of Erlangen-Nurnberg (Germany). After his post-doctoral stay at Stanford University, California (USA), he started in 1996 at BASF in herbicide research, wh