Target-site resistance to acetolactate synthase (ALS)-inhibiting herbicides in Amaranthus palmeri from Argentina

Authors
Larran, Alvaro Santiago; Palmieri, Valeria Esther; Perotti, Valeria Elisa; Lieber, Lucas; Tuesca, Daniel Horacio; Permingeat, Hugo Raúl
Publication Year
2017
Language
English
Format
article
Status
Published version
Description
BACKGROUND: Herbicide-resistant weeds are a serious problem worldwide. Recently, two populations of Amaranthus palmeri with suspected cross-resistance to acetolactate synthase (ALS)-inhibiting herbicides (R1 and R2) were found by farmers in two locations in Argentina (Vicuña Mackenna and Totoras, respectively). We conducted studies to confirm and elucidate the mechanism of resistance. RESULTS: We performed in vivo dose–response assays, and confirmed that both populations had strong resistance to chlorimuron-ethyl, diclosulam and imazethapyr when compared with a susceptible population (S). In vitro ALS activity inhibition tests only indicated considerable resistance to imazethapyr and chlorimuron-ethyl, indicating that other non-target mechanisms could be involved in diclosulam resistance. Subsequently, molecular analysis of als nucleotide sequences revealed three single base-pair mutations producing substitutions in amino acids previously associated with resistance to ALS inhibitors, A122, W574, and S653. CONCLUSION: This is the first report of als resistance alleles in A. palmeri in Argentina. The data support the involvement of a target-site mechanism of resistance to ALS-inhibiting herbicides. © 2017 Society of Chemical Industry.
Fil: Larran, Alvaro Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina
Fil: Palmieri, Valeria Esther. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Perotti, Valeria Elisa. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Fil: Lieber, Lucas. Bioheuris; Argentina
Fil: Tuesca, Daniel Horacio. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina
Fil: Permingeat, Hugo Raúl. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina
Subject
ACETOLACTATE SYNTHASE
ACETOLACTATE SYNTHASE INHIBITORS
AMARANTHUS PALMERI
CROSS-RESISTANCE
HERBICIDE RESISTANCE
WEEDS
Agricultura
Agricultura, Silvicultura y Pesca
CIENCIAS AGRÍCOLAS
Access level
Embargoed access
License
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repository
CONICET Digital (CONICET)
Institution
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identifier
oai:ri.conicet.gov.ar:11336/50387