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Review: Confirmation of Resistance to Herbicides and Evaluation of Resistance Levels

Published online by Cambridge University Press:  20 January 2017

Nilda R. Burgos*
Affiliation:
Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR 72704
Patrick J. Tranel
Affiliation:
Department of Crop Sciences, University of Illinois, Urbana, IL 61801
Jens C. Streibig
Affiliation:
Department of Agriculture and Ecology, The University of Copenhagen, Taastrup 2630, Denmark
Vince M. Davis
Affiliation:
Department of Agronomy, University of Wisconsin-Madison, WI 53706
Dale Shaner
Affiliation:
USDA-ARS, Fort Collins, CO 80526
Jason K. Norsworthy
Affiliation:
Department of Crop, Soil, and Environmental Sciences, University of Arkansas, Fayetteville, AR 72704
Christian Ritz
Affiliation:
Department of Basic Science and Environment, University of Copenhagen, Frederiksberg C, Denmark 1871
*
Corresponding author's E-mail: nburgos@uark.edu
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Abstract

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As cases of resistance to herbicides escalate worldwide, there is increasing demand from growers to test for weed resistance and learn how to manage it. Scientists have developed resistance-testing protocols for numerous herbicides and weed species. Growers need immediate answers and scientists are faced with the daunting task of testing an increasingly large number of samples across a variety of species and herbicides. Quick tests have been, and continue to be, developed to address this need, although classical tests are still the norm. Newer methods involve molecular techniques. Whereas the classical whole-plant assay tests for resistance regardless of the mechanism, many quick tests are limited by specificity to an herbicide, mode of action, or mechanism of resistance. Advancing knowledge in weed biology and genomics allows for refinements in sampling and testing protocols. Thus, approaches in resistance testing continue to diversify, which can confound the less experienced. We aim to help weed science practitioners resolve questions pertaining to the testing of herbicide resistance, starting with field surveys and sampling methods, herbicide screening methods, data analysis, and, finally, interpretation. More specifically, this article discusses approaches for sampling plants for resistance confirmation assays, provides brief overviews on the biological and statistical basis for designing and analyzing dose–response tests, and discusses alternative procedures for rapid resistance confirmation, including molecular-based assays. Resistance confirmation procedures often need to be slightly modified to suit a specific situation; thus, the general requirements as well as pros and cons of quick assays and DNA-based assays are contrasted. Ultimately, weed resistance testing research, as well as resistance management decisions arising from research, needs to be practical, feasible, and grounded in science-based methods.

Type
Review
Creative Commons
Creative Common License - CCCreative Common License - BYCreative Common License - NCCreative Common License - SA
This is an Open Access article, distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike licence (http://creativecommons.org/licenses/by-nc-sa/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the same Creative Commons license is included and the original work is properly cited.
Copyright
Copyright © Weed Science Society of America

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