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Full-Text Articles in Agronomy and Crop Sciences
Resistance To Herbicides Conferred By Amaranthus Palmeri Protoporphyrinogen Ix Oxidase Mutations, Pamela Carvalho De Lima
Resistance To Herbicides Conferred By Amaranthus Palmeri Protoporphyrinogen Ix Oxidase Mutations, Pamela Carvalho De Lima
Graduate Theses and Dissertations
Palmer amaranth (Amaranthus palmeri S. Wats.) is one of the most problematic agronomic weeds to control in fields across Arkansas. Thus far, this species has evolved resistance to several herbicides, including protoporphyrinogen IX oxidase (PPO) inhibitors. The majority of PPO-resistant Palmer amaranth populations harbor a target-site mutation (substitution or deletion of amino acids). The objective of this thesis was to identify the level of fomesafen resistance conferred by PPO2 mutations from Palmer amaranth. The experiments conducted aimed to (1) characterize the level of resistance conferred by the transgene Palmer amaranth ppo2 carrying ΔG210 mutation into the wild type rice (Oryza …
Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith
Glyphosate-Resistant Palmer Amaranth (Amaranthus Palmeri) In Arkansas: Resistance Mechanisms And Management Strategies, Griff Michael Griffith
Graduate Theses and Dissertations
Since 2000, there have been thirteen weed species confirmed resistant (R) to glyphosate in the United States, six of those resistant species are present in Arkansas. The goal of this research was to confirm and to determine the level of resistance in two R Palmer amaranth biotypes from Mississippi (MC-R) and Lincoln (LC-R) Counties, Arkansas, and one susceptible (S) biotype from Clarendon County, South Carolina, which had never been exposed to glyphosate. Shikimic acid concentration over time was significantly greater in the S biotype than both the MC-R and LC-R biotypes. The lethal dose required to kill 50% (LD50 …