The potential future roles of natural compounds and microbial bioherbicides in weed management in crops

Authors: DUKE, STEPHEN - University Of Mississippi; Pan, Zhiqiang - Peter; Bajsa-Hirschel, Joanna; Boyette, Clyde

Submitted to: Advances in Weed Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/8/2021
Publication Date: 1/10/2022
Citation: Duke, S.O., Pan, Z., Bajsa Hirschel, J.N., Boyette, C.D. 2022. The potential future roles of natural compounds and microbial bioherbicides in weed management in crops. Advances in Weed Science. 40(spe1):e020210054. https://doi.org/10.51694/AdvWeedSci/2022;40:seventy-five003.
DOI: https://doi.org/10.51694/AdvWeedSci/2022;40:seventy-five003

Interpretive Summary: In this review, we discuss the role of natural products as a solution for accumulating problems in pest management that negatively impact crop production and issues the herbicide discovery efforts are facing. A frequent and inevitable occurrence of herbicide-resistant weed species in agriculture force an extensive search for novel compounds with herbicidal activity. Natural products seem to be an excellent source of inspiration for exploring their phytotoxic activity scientists. Although despite invested years of efforts a number of promising, leading compounds with new mode of action is discontenting. Another issue this review covers is a rising demand for new solutions in pest control that fit in an environment-friendly course. Several bio-herbicides based on plant and microbial extracts or even containing live microbes are available. Nonetheless, in many cases some improvements have to be done e.g. extension of a shelf life, efficacy improvement, and mostly reduction of production costs to make profitable from an economical point of view their large-scale utilization in agriculture.

Technical Abstract: There is a popular demand for more natural means of pest management, including weed management, as well as a demand by farmers for herbicides with new chemistries and/or new modes of action and/or to which current weed resistances do not apply. Natural compounds offer a source compounds that can either meet these needs in their natural state or as templates for herbicides with better physicochemical properties for field use. In some cases, simply identifying a good herbicide target site with a natural phytotoxin can be valuable, even though that compound is not used as a template for new herbicides. Compared to insecticides and fungicides, natural compounds have been under-utilized for herbicides. Despite their need, living, microbial biocontrol agents have had little impact on weed management in crops, despite decades of research to discover and develop such products. Management of insect and plant pathogens with microbial biopesticides has been much more successful. The reasons for this and possible solutions are discussed. Killed microbial preparations containing potent phytotoxins avoid some of the issues with live microbes, and such products are under development. This type of product can also offer more than one new mode of action in a single preparation. Precision and smart spray systems can improve the economics of both natural product-based herbicides and microbial bioherbicides.