Why are there no widely successful microbial bioherbicides for weed management in crops?

Authors: DUKE, STEPHEN - University Of Mississippi

Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/21/2023
Publication Date: 6/15/2023
Citation: Duke, S.O. 2023. Why are there no widely successful microbial bioherbicides for weed management in crops?. Pest Management Science. 80:56-94. https://doi.org/10.1002/ps.7595.
DOI: https://doi.org/10.1002/ps.7595

Interpretive Summary: Microbial biopesticides to control plant pathogens and insects in crops have had significant success. However, there have been relatively few successes for microbiol bioherbicides in crops, despite considerable publication and patent activity and commercial product introductions in this area. Marketed microbial bioherbicide products for use in agriculture have been largely unsuccessful. This paper covers the potential advantages of successful microbial bioherbicides, as well as the biological and technical issues that have limited the success of such products. Technologies to overcome the problems that have limited the success of these products are discussed. The advantages of using killed microbial products (e.g., cell-free filtrates) over living microbial products as bioherbicides is detailed. A commercialized mycoherbicide that has been selected for in the lab for control of the parasitic weed Striga hermonthica is being used with some success in Africa, indicating that non-transgenic modification of the genetics of bioherbicide microbes for improved efficacy is acceptable to some regulatory authorities.

Technical Abstract: Microbial biopesticides to control plant pathogens and insects in crops have had significant success. However, there have been relatively few successes for microbiol bioherbicides in crops, despite considerable publication and patent activity and commercial product introductions in this area. Marketed microbial bioherbicide products for use in agriculture have been largely unsuccessful. This paper covers the potential advantages of successful microbial bioherbicides, as well as the biological and technical issues that have limited the success of such products. Technologies to overcome the problems that have limited the success of these products are discussed. The advantages of using killed microbial products (e.g., cell-free filtrates) over living microbial products as bioherbicides is detailed. A commercialized mycoherbicide that has been selected for in the lab for control of the parasitic weed Striga hermonthica is being used with some success in Africa, indicating that non-transgenic modification of the genetics of bioherbicide microbes for improved efficacy is acceptable to some regulatory authorities.