{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/117687"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/117687","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Investigation of oxidative stress responses in Amaranthus with colorimetric assays","abstract":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-12-01","abstract_html":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-12-01","abstract_has_math":false,"creators":["Woods, James W."],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Crop Sciences","degree_department":null,"school":null,"contributors":["Riggins, Chance W.","Villamil, Maria B.","Rodriguez-Zas, Sandra L."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-12","date_published":"2022-12","updated_at":"2026-07-22T22:24:56Z","subjects":["Amaranthus","Oxidative Stress","Lipid Peroxidation","Malondialdehyde","Mda","Herbicide Resistance","Drought"],"languages":["en","eng"],"rights":["Copyright 2022 James Woods"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/117687","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Riggins, Chance W.","Villamil, Maria B.","Rodriguez-Zas, Sandra L."]},{"key":"dc:creator","label":"Author","values":["Woods, James W."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2022-12","2022-12-08"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Crop Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Amaranthus","Oxidative Stress","Lipid Peroxidation","Malondialdehyde","Mda","Herbicide Resistance","Drought"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2022 James Woods"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/117687"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-12-01","The student, James Woods, accepted the attached license on 2022-12-06 at 15:17.","The student, James Woods, submitted this Thesis for approval on 2022-12-06 at 16:07.","This Thesis was approved for publication on 2022-12-08 at 10:06.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18762 on 2023-04-12 at 08:14:14","Amaranthus species are paradoxically reviled as “superweeds” and revered as “superfoods.” This distinction is a matter of perspective, but it also reflects a suite of shared biological and adaptive traits among species in the genus. Adaptive traits that define some amaranths as aggressive weeds (e.g., prolific seed output, rapid growth, and high tolerance to abiotic stress) can be reframed as valuable agronomic traits for other amaranths grown as pseudocereals or leafy vegetable crops. Cultivated amaranths are recognized for their high nutritional profiles in both seeds and leaves, which are rich in protein, dietary fiber, flavonoids, and vitamins. Weedy amaranth species are notorious for adaptability to a wide range of agricultural settings and evolving herbicide resistance and thus offer excellent case studies for understanding stress response mechanisms. Amaranths are also highly valued as ornamentals due to the added pigmentation trait, expressed in many visually striking patterns in leaves, stems, and floral tissues. Betalains are the principal source of pigmentation in amaranths and are represented by two main classes: betacyanins (red-magenta colors) and betaxanthins (yellow-orange). Betalain pigments have been implicated in possible antioxidant roles in helping amaranths cope with oxidative stress. Still, questions remain regarding their specific roles among diverse pigmented phenotypes and in concert with other plant enzymatic and non-enzymatic antioxidant systems. Greenhouse and laboratory investigations were thus conducted to assess the effects of two stress treatments (i.e., herbicide and drought) on pigmented and non-pigmented weedy and cultivated Amaranthus species using two commonly used colorimetric assays. Specifically, the thiobarbituric acid reactive substances (TBARS) assay and potassium iodide (KI) assay were used to measure two indicators of oxidative stress, malondialdehyde (MDA) and hydrogen peroxide (H2O2), respectively. Protocol optimizations were made for both assays, specifically focusing on betalain pigments as antioxidants and potentially interfering compounds for these color-based assays. Caveats are discussed for each assay, and recommendations are made regarding how these assays should be implemented and interpreted for amaranths and other betalain-producing plants."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Investigation of oxidative stress responses in Amaranthus with colorimetric assays"]}]}],"canonical_facts":{"dc:contributor":["Riggins, Chance W.","Villamil, Maria B.","Rodriguez-Zas, Sandra L."],"dc:creator":["Woods, James W."],"dc:date":["2022-12","2022-12-08"],"dc:description":["Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2024-12-01","The student, James Woods, accepted the attached license on 2022-12-06 at 15:17.","The student, James Woods, submitted this Thesis for approval on 2022-12-06 at 16:07.","This Thesis was approved for publication on 2022-12-08 at 10:06.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18762 on 2023-04-12 at 08:14:14","Amaranthus species are paradoxically reviled as “superweeds” and revered as “superfoods.” This distinction is a matter of perspective, but it also reflects a suite of shared biological and adaptive traits among species in the genus. Adaptive traits that define some amaranths as aggressive weeds (e.g., prolific seed output, rapid growth, and high tolerance to abiotic stress) can be reframed as valuable agronomic traits for other amaranths grown as pseudocereals or leafy vegetable crops. Cultivated amaranths are recognized for their high nutritional profiles in both seeds and leaves, which are rich in protein, dietary fiber, flavonoids, and vitamins. Weedy amaranth species are notorious for adaptability to a wide range of agricultural settings and evolving herbicide resistance and thus offer excellent case studies for understanding stress response mechanisms. Amaranths are also highly valued as ornamentals due to the added pigmentation trait, expressed in many visually striking patterns in leaves, stems, and floral tissues. Betalains are the principal source of pigmentation in amaranths and are represented by two main classes: betacyanins (red-magenta colors) and betaxanthins (yellow-orange). Betalain pigments have been implicated in possible antioxidant roles in helping amaranths cope with oxidative stress. Still, questions remain regarding their specific roles among diverse pigmented phenotypes and in concert with other plant enzymatic and non-enzymatic antioxidant systems. Greenhouse and laboratory investigations were thus conducted to assess the effects of two stress treatments (i.e., herbicide and drought) on pigmented and non-pigmented weedy and cultivated Amaranthus species using two commonly used colorimetric assays. Specifically, the thiobarbituric acid reactive substances (TBARS) assay and potassium iodide (KI) assay were used to measure two indicators of oxidative stress, malondialdehyde (MDA) and hydrogen peroxide (H2O2), respectively. Protocol optimizations were made for both assays, specifically focusing on betalain pigments as antioxidants and potentially interfering compounds for these color-based assays. Caveats are discussed for each assay, and recommendations are made regarding how these assays should be implemented and interpreted for amaranths and other betalain-producing plants."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/117687"],"dc:language":["en","eng"],"dc:rights":["Copyright 2022 James Woods"],"dc:subject":["Amaranthus","Oxidative Stress","Lipid Peroxidation","Malondialdehyde","Mda","Herbicide Resistance","Drought"],"dc:title":["Investigation of oxidative stress responses in Amaranthus with colorimetric assays"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Crop Sciences"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:56Z"}