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Evolution of Resistance to Auxinic Herbicides: Historical Perspectives, Mechanisms of Resistance, and Implications for Broadleaf Weed Management in Agronomic Crops

Published online by Cambridge University Press:  20 January 2017

J. Mithila ,
J. Christopher Hall ,
William G. Johnson ,
Kevin B. Kelley  and
Dean E. Riechers
J. Mithila
Affiliation:
School of Environmental Sciences, University of Guelph, Ontario, Canada N1G 2W1
J. Christopher Hall
Affiliation:
School of Environmental Sciences, University of Guelph, Ontario, Canada N1G 2W1
William G. Johnson
Affiliation:
Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907
Kevin B. Kelley
Affiliation:
AgraServ, Inc., American Falls, ID 83211
Dean E. Riechers*
Affiliation:
Department of Crop Sciences, University of Illinois, Urbana, IL 61801
*
Corresponding author's E-mail: riechers@illinois.edu
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Abstract

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Auxinic herbicides are widely used for control of broadleaf weeds in cereal crops and turfgrass. These herbicides are structurally similar to the natural plant hormone auxin, and induce several of the same physiological and biochemical responses at low concentrations. After several decades of research to understand the auxin signal transduction pathway, the receptors for auxin binding and resultant biochemical and physiological responses have recently been discovered in plants. However, the precise mode of action for the auxinic herbicides is not completely understood despite their extensive use in agriculture for over six decades. Auxinic herbicide-resistant weed biotypes offer excellent model species for uncovering the mode of action as well as resistance to these compounds. Compared with other herbicide families, the incidence of resistance to auxinic herbicides is relatively low, with only 29 auxinic herbicide-resistant weed species discovered to date. The relatively low incidence of resistance to auxinic herbicides has been attributed to the presence of rare alleles imparting resistance in natural weed populations, the potential for fitness penalties due to mutations conferring resistance in weeds, and the complex mode of action of auxinic herbicides in sensitive dicot plants. This review discusses recent advances in the auxin signal transduction pathway and its relation to auxinic herbicide mode of action. Furthermore, comprehensive information about the genetics and inheritance of auxinic herbicide resistance and case studies examining mechanisms of resistance in auxinic herbicide-resistant broadleaf weed biotypes are provided. Within the context of recent findings pertaining to auxin biology and mechanisms of resistance to auxinic herbicides, agronomic implications of the evolution of resistance to these herbicides are discussed in light of new auxinic herbicide-resistant crops that will be commercialized in the near future.

Keywords

Auxinic herbicidesdominant traitevolution of resistancefitness costherbicide-resistant cropsmode of actionmechanism of resistanceplant growth regulatorrecessive trait
Type
Review
Information
Weed Science , Volume 59 , Issue 4 , December 2011 , pp. 445 - 457
Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright
Copyright © Weed Science Society of America

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