Molecular targets of herbicides and fungicides – are there useful overlaps for fungicide discovery?

Authors: DUKE, STEPHEN - University Of Mississippi; Pan, Zhiqiang - Peter; Bajsa-Hirschel, Joanna; Tamang, Prabin; HAMMERSCHMIDT, RAYMOND - Michigan State University; LORSBACH, BETH - Nufarm; SPARKS, THOMAS - Agrilucent Llc

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/21/2023
Publication Date: 12/15/2023
Citation: Duke, S.O., Pan, Z., Bajsa-Hirschel, J.N., Tamang, P., Hammerschmidt, R., Lorsbach, B.A, and Sparks, T.C. 2023. Molecular targets of herbicides and fungicides - are there useful overlaps for fungicide discovery? J. Agric. Food Chem. 71:20532-20548. https://doi.org/10.1021/acs.jafc.3c07166
DOI: https://doi.org/10.1021/acs.jafc.3c07166

Interpretive Summary: New fungicide modes of action are needed for fungicide resistance management strategies. Several commercial herbicide targets are found in fungi that are not utilized by commercial fungicides. This review article discusses the molecular target sites possibly shared by both fungicides and herbicides. The potential targets include the biosynthetic pathways that make fatty acids, amino acids, pigments, vitamins, and proteins. Some herbicides are already effective against fungi or could be modified to become better fungicides. For example, some herbicides that inhibit the production of amino acids or vitamins also stop the growth of fungi. Moreover, some herbicides may have indirect benefits for certain crops by reducing fungal infections. Using a pesticide that has both herbicidal and fungicidal activity based on the same target could reduce the amount of pesticide applied.

Technical Abstract: New fungicide modes of action are needed for fungicide resistance management strategies. Several commercial herbicide targets are found in fungi that are not utilized by commerical fungicides are discussed as possible fungicide molecular targets. These are acetyl CoA carboxylase, acetolactate synthase, 5-enolpyruvylshikimate-3-phosphate synthase, glutamine synthase, phytoene desaturase, protoporphyrinogen oxidase, long chain fatty acid synthase, dihydropteroate synthase, hydroxyphenyl pyruvate dioxygenase, and Ser/Thr protein phosphatase. Some of the inhibitors of these herbicide targets appear to either be good fungicides or good leads for new fungicides. For example, some acetolactate synthase and dihydropteroate inhibitors are excellent fungicides. There is evidence that some herbicides have indirect benefits to certain crops, due to their effects on fungal crop pathogens. Using a pesticide with both herbicide and fungicide activity based on the same molecular target could reduce the total amount of pesticide used.