Dissecting phenotypic inheritance of very-long-chain fatty acid inhibitor resistance in waterhemp (Amaranthus tuberculatus) using a novel greenhouse assay: 'PRIM'
type: CreativeWork
description: Weedy plant species, especially within the genus Amaranthus, capable of surviving the selective phytotoxic effects of an EPA-approved chemical at its most vulnerable growth stage, represent a clear and present danger to the United States and perhaps the world. Such a threat, if left unchecked, may very well thwart future generations’ ability to feed the world's growing population. Herbicides applied preemergence (PRE) are on the frontlines in the arms race of herbicide formulation development and rotating sites-of-action (SoA) to ameliorate herbicide resistance in weedy plants. A pseudo-POST germination method is needed to accurately phenotype known sensitive and resistant populations through a direct chemical × seedling interaction method capable of delivering low herbicide concentrations. Non-target site resistance (NTSR) to Group 15 herbicides represents an important research topic for the future of weed science. The genetic basis for Group 15 resistance is still unknown, with several genetic and environmental (G × E) factors likely involved. Environmental, ecological, and genetic factors are compounded with additional variability in the dioecious species, waterhemp [Amaranthus tuberculatus (Moq.) Sauer]. The use of a single (one male × one female) cross provides a more controlled plant breeding environment, which is important when breeding a dioecious weed species whereby maternal and paternally derived resistant lines of waterhemp were independently produced. This crossing strategy used over generations of selection yielded a pseudo-homogenous waterhemp population ideal for the crossing experiments with a sensitive waterhemp population used in this study. Additionally, phenotypic analysis of resistant × sensitive progeny revealed the probability of resistance to help determine effective weed management strategies for NTSR waterhemp populations. Chapter 1 of this thesis covers a literature review of the Group 15 herbicides, S-metolachlor, and pyroxasulfone. Thei…
abstract: Weedy plant species, especially within the genus Amaranthus, capable of surviving the selective phytotoxic effects of an EPA-approved chemical at its most vulnerable growth stage, represent a clear and present danger to the United States and perhaps the world. Such a threat, if left unchecked, may very well thwart future generations’ ability to feed the world's growing population. Herbicides applied preemergence (PRE) are on the frontlines in the arms race of herbicide formulation development and rotating sites-of-action (SoA) to ameliorate herbicide resistance in weedy plants. A pseudo-POST germination method is needed to accurately phenotype known sensitive and resistant populations through a direct chemical × seedling interaction method capable of delivering low herbicide concentrations. Non-target site resistance (NTSR) to Group 15 herbicides represents an important research topic for the future of weed science. The genetic basis for Group 15 resistance is still unknown, with several genetic and environmental (G × E) factors likely involved. Environmental, ecological, and genetic factors are compounded with additional variability in the dioecious species, waterhemp [Amaranthus tuberculatus (Moq.) Sauer]. The use of a single (one male × one female) cross provides a more controlled plant breeding environment, which is important when breeding a dioecious weed species whereby maternal and paternally derived resistant lines of waterhemp were independently produced. This crossing strategy used over generations of selection yielded a pseudo-homogenous waterhemp population ideal for the crossing experiments with a sensitive waterhemp population used in this study. Additionally, phenotypic analysis of resistant × sensitive progeny revealed the probability of resistance to help determine effective weed management strategies for NTSR waterhemp populations. Chapter 1 of this thesis covers a literature review of the Group 15 herbicides, S-metolachlor, and pyroxasulfone. Thei…
author: Kerr, Dylan R
language: en
keywords: S-metolachlor, pyroxasulfone, soilless, vermiculite, preemergence, PRE, resistance, waterhemp
date published: 2022-01-12T21:47:00Z
date modified: 2026-07-22T22:24:53Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/113094