Origins of new modes of action for fungicides, herbicides and insecticides: a review and analysis.

New modes of action (MoAs) can be a key driver for the discovery of new crop protection compounds, facilitating resistance management programs and providing the basis for compounds with improved toxicological and environmental attributes. There are numerous approaches to the discovery of new crop protection compounds that can be grouped broadly into competitor inspired, next generation, natural products, and bioactive hypothesis. The latter group, bioactive hypothesis, is itself composed of an array of approaches that include exploring novel areas of chemistry, testing chemistries from other therapeutic areas, bioactive scaffolds, internal libraries, and many more. In theory, all of these approaches can lead to new crop protection compounds with new MoAs. Herein, we provide an analysis of the approaches that have been used to discover fungicides, herbicides, and insecticides with different MoAs. The goal of this analysis is to identify the approaches based on available data which are most likely to yield pest management compounds with new MoAs. © 2025 Society of Chemical Industry.