A novel genomic approach to herbicide and herbicide mode of action discovery.

A herbicide with a new mode of action has not been commercialized for more than 30 years. A recent paper describes a novel genomic approach to herbicide and herbicide mode of action discovery. Analysis of a microbial gene cluster revealed that it encodes genes for both the biosynthetic pathway for production of the sesquiterpene aspterric acid and an aspterric acid-resistant form of dihydroxy acid dehydratase (DHAD), its target enzyme. Aspterric acid is weak compared with commercial synthetic herbicides, and whether DHAD is a good herbicide target is unclear from this study. Nevertheless, this genomic approach provides a novel strategy for the discovery of herbicides with new modes action.