The search for new herbicide mechanisms of action: Is there a 'holy grail'?

New herbicide modes of action (MOAs) are in great demand because of the burgeoning evolution of resistance of weeds to existing commercial herbicides. This need has been exacerbated by the almost complete lack of introduction of herbicides with new MOAs for almost 40 years. There are many highly phytotoxic compounds with MOAs not represented by commercial herbicides, but neither these compounds nor structural analogues have been developed as herbicides for a variety of reasons. Natural products provide knowledge of many MOAs that are not being utilized by commercial herbicides. Other means of identifying new herbicide targets are discussed, including pharmaceutical target sites and metabolomic and proteomic information, as well as the use of artificial intelligence and machine learning to predict herbicidal compounds with new MOAs. Information about several newly discovered herbicidal compounds with new MOAs is summarized. The currently increased efforts of both established companies and start-up companies are likely to result in herbicides with new MOAs that can be used in herbicide resistance management within the next decade. (c) 2021 Society of Chemical Industry.

Automated summary

The demand for new herbicide modes of action has surged due to the evolving resistance of weeds to existing commercial herbicides. Natural products possess many potential new modes of action that have not been utilized by current herbicides, but have yet to be developed for various reasons. Efforts are being made to identify new herbicide targets through pharmaceutical target sites, metabolomic and proteomic information, and the use of artificial intelligence and machine learning. It is likely that new herbicides with new modes of action will be introduced within the next decade to address herbicide resistance management.