Natural products, their derivatives, mimics and synthetic equivalents: role in agrochemical discovery

Abstract

Natural products (NPs) have a long history as a source of, and inspiration for, novel agrochemicals. Many of the existing herbicides, fungicides, and insecticides have their origins in a wide range of NPs from a variety of sources. Owing to the changing needs of agriculture, shifts in pest spectrum, development of resistance, and evolving regulatory requirements, the need for new agrochemical tools remains as critical as ever. As such, NPs continue to be an important source of models and templates for the development of new agrochemicals, demonstrated by the fact that NP models exist for many of the pest control agents that were discovered by other means. Interestingly, there appear to be distinct differences in the success of different NP sources for different pesticide uses. Although a few microbial NPs have been important starting points in recent discoveries of some insecticidal agrochemicals, historically plant sources have contributed the most to the discovery of new insecticides. In contrast, fungi have been the most important NP sources for new fungicides. Like insecticides, plant-sourced NPs have made the largest contribution to herbicide discovery. Available data on 2014 global sales and numbers of compounds in each class of pesticides indicate that the overall impact of NPs to the discovery of herbicides has been relatively modest compared to the impact observed for fungicides and insecticides. However, as new sourcing and approaches to NP discovery evolve, the impact of NPs in all agrochemical arenas will continue to expand. © 2016 Society of Chemical Industry.

Recent advances in allelopathy for weed control: from knowledge to applications

“…This shows increased interest in pest control using natural products. During this time, numerous developments have occurred, and many new and old allelochemicals have been discovered and/or studied, strengthening interest in natural products as inspiration for novel agrochemicals . Thus, an update to our previous review focused on phytotoxicity and the chemical aspects of allelopathy is due …”

Natural products: a strategic lead generation approach in crop protection discovery

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Removing constraints to sustainable food production: new ways to exploit secondary metabolism from companion planting and GM

“…In addition to there being more opportunities than from pesticidal proteins, e.g. Bt crops against insect pests, the secondary metabolites of plants already show a growing opportunity as, or for the development of, insecticides . By choosing highly biologically active compounds from the wide range of natural products available, including insect toxicants, pheromones and other semiochemicals as well as some allelopathic agents, there will be little loss of photosynthate via this form of defence and with the latest GM technologies no other detracting phenotypic changes, for example Bruce et al …”

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