Herbicides Inhibiting Branched Chain Amino Acid Biosynthesis

Chemicals inhibiting the biosynthesis of branched-chain amino acids form a new and promising class of herbicides. This volume discusses in an authoritative way recent developments in this field and covers important aspects of these potent herbicides (synthesis, structure-activity, mode of action, selectivity, weed resistance, metabolism).

Developments in the understanding of herbicide activity and toxicology have expanded tremendously in the past fifteen years. Research on the mechanism of action of most major classes of herbicide chemistry has provided scientists with excellent insight into enzyme targets. More recently, developments in molecular biology have provided information about herbicide action at the genetic level. Less well understood are the toxicological aspects of herbicide activity that culminate in plant injury or death. Toxicology, Biochemistry and Molecular Biology of Herbicide Activity is a review of the recent literature on most of the major classes of herbicide chemistry in commercial use. The chapters include information about different aspects of herbicide activity related to photosynthesis, inhibition of amino acid biosynthesis, disruption of cell division and microtubule assembly, activity of phytohormone (auxin) mimics, inhibition of fatty acid biosynthesis and some developments in the understanding of herbicide resistance.

This book reflects the growing interest in the pathways of the biosynthesis of branched-chain amino acids. With contributions from various subdisciplines, it represents an extensive state-of-the-art report. Numerous aspects of the biosynthesis of branched-chain amino acids are covered, such as control of gene expression, the interaction among metabolic pathways under physiological conditions and unusual circumstances, and the stereochemical and mechanistic aspects of enzymes involved. It also considers possible applications to biotechnological problems and the development of novel herbicides. Special Feature: An extensive general bibliography to help the reader find further important information on the subject.

This publication is based on the plant processes and reaction sites for which reliable knowledge on both their physiology and biochem-istry and the mode of herbicidal action is available. Targets of the agrochemical research, such as enzymes of biosynthetic pathways or herbicide-binding peptides in the photosynthetic membrane, are highlighted. Detailed knowledge about the target sites will allow bio-chemical model systems to evaluate the biological activity of newly synthesized compounds before their conventional screening in the greenhouse. Quantitative structure/activity relationships should be performed more reliably with simple biological species or enzymol-ogy assays, to aid in the rational design of pesticides. This text is highly valuable for plant physiologists, pathologists, and chemists in the agrochemical industry and universities.

A review of the most important areas of the biochemistry of herbicide action. The introductory chapter begins with the field of herbicide discovery, followed by chapters dealing with the herbicidal inhibition of photosynthesis, carotenoid biosynthesis, lipid biosynthesis, and amino acid biosynthesis. The metabolism of herbicides is discussed with particular reference to the formation of toxic components from non-toxic chemicals, and also the inactivation of toxic chemicals as a basis for selectivity. The final chapters are concerned with mechanisms of herbicide resistance in plants and the possibility of transferring resistance to susceptible crops. A glossary of the most important herbicidal chemicals mentioned in the text is included.