Confirmation and Control of Triazine and 4-Hydroxyphenylpyruvate Dioxygenase-Inhibiting Herbicide-Resistant Palmer Amaranth (Amaranthus palmeri) in Nebraska. (March 2014)

• Record Type: Journal Article
• Authors: Jhala, Amit J.; Sandell, Lowell D.; Rana, Neha; Kruger, Greg R.; Knezevic, Stevan Z.
• Is Part Of: Weed technology. Volume 28:Number 1(2014)
• Page Start: 28
• Page End: 38
• Publication Date: 2014-03
• Subjects: 2, 4-D, -- atrazine, -- bromoxynil, -- dicamba, fluthiacet-methyl, -- glufosinate, -- glyphosate, -- halosulfuron-methyl, -- lactofen, -- mesotrione, -- primisulfuron-methyl, -- pyrasulfotole, -- tembotrione, -- thiencarbazone-methyl, -- topramezone, -- Palmer amaranth, Amaranthus palmeri S. Wats, -- corn, Zea mays L., -- soybean, Glycine max (L.) Merr; Dose response, -- herbicide resistance, -- resistance management, -- weed biomass; Weeds -- Periodicals; Weeds -- Control -- Periodicals; 632.5
• DOI: 10.1614/WT-D-13-00090.1
• Languages: English
• ISSNs: 0890-037X

Abstract

Abstract : Palmer amaranth is a difficult-to-control broadleaf weed that infests corn and soybean fields in south-central and southwestern Nebraska and several other states in the United States. The objectives of this research were to confirm triazine and 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicide-resistant Palmer amaranth in Nebraska and to determine sensitivity and efficacy of POST-applied corn herbicides for control of resistant and susceptible Palmer amaranth biotypes. Seeds from a putative HPPD-resistant Palmer amaranth biotype from Fillmore County, NE were collected from a seed corn production field in fall 2010. The response of Palmer amaranth biotypes to 12 rates (0 to 12×) of mesotrione, tembotrione, topramezone, and atrazine was evaluated in a dose–response bioassay in a greenhouse. On the basis of the values at the 90% effective dose (ED90 ) level, the analysis showed a 4- to 23-fold resistance depending upon the type of HPPD-inhibiting herbicide being investigated and susceptible biotype used for comparison. This biotype also had a 9- to 14-fold level of resistance to atrazine applied POST. Results of a POST-applied herbicide efficacy study suggested a synergistic interaction between atrazine and HPPD-inhibiting herbicides that resulted in > 90% control of all Palmer amaranth biotypes. The resistant biotype had a reduced sensitivity to acetolactate synthase inhibiting herbicides (halosulfuron and primisulfuron), a photosystem-II inhibitor (bromoxynil), and a protoporphyrinogen oxidase inhibitor (fluthiacet-methyl). Palmer amaranth biotypes were effectively controlled (≥ 90%) with glyphosate, glufosinate, and dicamba, whereas 2, 4-D ester provided 81 to 83% control of the resistant biotype and > 90% control of both susceptible biotypes.