Biorational Reflections in Agricultural Chemical Research

Abstract

The future of agricultural chemical research will be determined by three major factors: a) by the diminishing success rate of conventional synthesis and biological screening procedures; b) by the accentuating demand on agriculture to adapt its technologies to the preservation of limited natural resources, such as soil, water, energy, etc., and c) by the accelerating and impressive acquisition of new biochemical and biomolecular information on crop plants and pest organisms. All these factors will encourage the use of (bio-)rational concepts and approaches in designing efficient chemicals for crop production and protection. In addition, mid- and long-term, these chemicals will be supplemented by biotechnological solutions. 
However, to make biorational methods and tools more successful than they are at present, a number of impediments have to be overcome, including the complexity of control-factors in crop ecosystems and the relevance of the biological testing procedures applied. 
The different conceptual approaches and modern biorational methods are illustrated by recent practical examples from four areas of indication: insect control (sulfenylated carbamates), plant growth regulation (mediation of ethylene release), disease control (triazole fungicides) and weed control (photosynthesis-inhibiting herbicides).