Distribution of glyphosate-resistant Amaranthus spp. in Nebraska

Bruno C. Vieira, Spencer L. Samuelson, Guilherme S. Alves, Todd A. Gaines, Rodrigo Werle, Greg R. Kruger

Research output: Contribution to journalArticlepeer-review

28 Citations (Scopus)

Abstract

BACKGROUND Palmer amaranth (Amaranthus palmeri S. Wats.), common waterhemp (Amaranthus tuberculatus var. rudis), and redroot pigweed (Amaranthus retroflexus L.) are major weeds occurring in fields throughout Nebraska with recurrent grower complaints regarding control with glyphosate. The objective of this study was to investigate the frequency and distribution of glyphosate-resistant Palmer amaranth, common waterhemp, and redroot pigweed populations in Nebraska. The study also aimed to investigate how agronomic practices influence the occurrence of glyphosate resistance in the three Amaranthus species. RESULTS Glyphosate resistance was widespread in common waterhemp (81% of the screened populations), few Palmer amaranth populations were glyphosate-resistant (6% of the screened populations), whereas no glyphosate-resistant redroot pigweed populations were identified in Nebraska. Weed species, geographic region within the state, and current crop were the most important factors predicting the occurrence of glyphosate resistance in fields infested with Amaranthus species in Nebraska. CONCLUSION The intensive glyphosate selection pressure exerted in soybean (Glycine max) fields in eastern Nebraska is one of the major factors causing widespread occurrence of glyphosate resistance in common waterhemp in the state. The relatively low frequency of glyphosate-resistant Palmer amaranth in the state highlights the importance of the application timing and the adoption of multiple modes of action in weed management practices to delay the evolution of glyphosate resistance. (c) 2017 Society of Chemical Industry
Original languageEnglish
Pages (from-to)2316-2324
Number of pages9
JournalPest Management Science
Volume74
Issue number10
DOIs
Publication statusPublished - Oct 2018
Externally publishedYes
Event2nd Global Herbicide Resistance Challenge (GHRC) Conference - Denver, Colombia
Duration: 14 May 201718 May 2017

Fingerprint

Dive into the research topics of 'Distribution of glyphosate-resistant Amaranthus spp. in Nebraska'. Together they form a unique fingerprint.

Cite this