{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/90798"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/90798","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Fitness costs of herbicide resistance traits in common waterhemp (Amaranthus tuberculatus)","abstract":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-05-01","abstract_html":"Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-05-01","abstract_has_math":false,"creators":["Wu, Chenxi"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Crop Sciences","degree_department":null,"school":null,"contributors":["Tranel, Patrick J.","Davis, Adam S.","Diers, Brian W.","Pittendrigh, Barry R."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-07-07T20:27:48Z","date_published":"2016-07-07T20:27:48Z","updated_at":"2026-07-22T22:26:34Z","subjects":["Fitness Costs","herbicide resistance","waterhemp"],"languages":["en"],"rights":["Copyright 2016 Chenxi Wu"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/90798","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Tranel, Patrick J.","Davis, Adam S.","Diers, Brian W.","Pittendrigh, Barry R."]},{"key":"dc:creator","label":"Author","values":["Wu, Chenxi"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2016-07-07T20:27:48Z","2018-07-08T09:15:33Z","2016-04-22","2016-05"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Crop Sciences"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"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":["Fitness Costs","herbicide resistance","waterhemp"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2016 Chenxi Wu"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/90798"]}]},{"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 2018-05-01","The student, Chenxi Wu, accepted the attached license on 2016-04-19 at 13:19.","The student, Chenxi Wu, submitted this Dissertation for approval on 2016-04-21 at 09:14.","A three-year multigenerational greenhouse study was conducted to determine the fitness costs of five herbicide resistances (HR) in waterhemp. In the study, a synthetic waterhemp population segregating for five types of HR was subjected to competitive growth conditions in the absence of herbicide selection for six generations. The resistance frequencies of each generation were determined from both whole-plant herbicide treatments (glyphosate, atrazine, 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors) and molecular markers (acetolactate synthase (ALS) and protoporphyrinogen oxidase (PPO) inhibitors). Our result is the first report of the fitness costs for NTR to atrazine and HPPD inhibitors, as well as for the different fitness costs of two EPSPS alterations. Our results indicate that the resistance traits have no fitness costs, with the exception that ALS inhibitor resistance conferred by T574L target-site substitution had a minor fitness cost. Specifically, the relative fitnesses determined from the overall resistance frequency changes were 0.92, 1.02, 1.09, 0.97, and 1.07 for resistances to ALS and PPO inhibitors, atrazine, HPPD inhibitors, and glyphosate, respectively. It was also determined that glyphosate resistance (GR) in the study population was endowed by at least two resistance mechanisms (P106S target-site mutation and amplification of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene). A phenotype-genotype association analysis was conducted to determine if the two GR mechanisms differ in their fitness costs and significance in conferring resistance. No fitness penalty was observed for the P106S substitution, while EPSPS amplification had a significant fitness cost (relative fitness of 1.12 and 0.72, respectively). EPSPS amplification and the P106S mutation did not fully account for glyphosate resistance in the population. The evolution of GR likely is a result of the interplay of different resistance mechanisms, with relative fitness of the mechanisms— both in the presence and absence of glyphosate—playing roles. The results from this novel study add to a growing body of evidence indicating that herbicide rotation is not an effective resistance management strategy because most herbicide resistances lack significant fitness costs.","This Dissertation was approved for publication on 2016-04-22 at 13:29.","DSpace SAF Submission Ingestion Package generated from Vireo submission #9342 on 2016-07-07 at 13:50:07","Made available in DSpace on 2016-07-07T20:27:48Z (GMT). No. of bitstreams: 3 WU-DISSERTATION-2016.pdf: 73642028 bytes, checksum: 19aae429961cb52f39ddfee2b3e57deb (MD5) LICENSE.txt: 4206 bytes, checksum: 674b6533cf6f06ad96d3aa663caa4592 (MD5) PROQUEST_LICENSE.txt: 4552 bytes, checksum: 37c0e03b38d83d0bcf13c57307ca8039 (MD5) Previous issue date: 2016-04-22","Embargo set by: Seth Robbins for item 93150 Lift date: 2018-07-07T20:28:14Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system","Embargo set by: Seth Robbins for item 93150 Lift date: 2018-07-07T20:35:34Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system","U of I Only Restriction Lifted for Item 93150 on 2018-07-08T09:15:33Z."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Fitness costs of herbicide resistance traits in common waterhemp (Amaranthus tuberculatus)"]}]}],"canonical_facts":{"dc:contributor":["Tranel, Patrick J.","Davis, Adam S.","Diers, Brian W.","Pittendrigh, Barry R."],"dc:creator":["Wu, Chenxi"],"dc:date":["2016-07-07T20:27:48Z","2018-07-08T09:15:33Z","2016-04-22","2016-05"],"dc:description":["Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2018-05-01","The student, Chenxi Wu, accepted the attached license on 2016-04-19 at 13:19.","The student, Chenxi Wu, submitted this Dissertation for approval on 2016-04-21 at 09:14.","A three-year multigenerational greenhouse study was conducted to determine the fitness costs of five herbicide resistances (HR) in waterhemp. In the study, a synthetic waterhemp population segregating for five types of HR was subjected to competitive growth conditions in the absence of herbicide selection for six generations. The resistance frequencies of each generation were determined from both whole-plant herbicide treatments (glyphosate, atrazine, 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors) and molecular markers (acetolactate synthase (ALS) and protoporphyrinogen oxidase (PPO) inhibitors). Our result is the first report of the fitness costs for NTR to atrazine and HPPD inhibitors, as well as for the different fitness costs of two EPSPS alterations. Our results indicate that the resistance traits have no fitness costs, with the exception that ALS inhibitor resistance conferred by T574L target-site substitution had a minor fitness cost. Specifically, the relative fitnesses determined from the overall resistance frequency changes were 0.92, 1.02, 1.09, 0.97, and 1.07 for resistances to ALS and PPO inhibitors, atrazine, HPPD inhibitors, and glyphosate, respectively. It was also determined that glyphosate resistance (GR) in the study population was endowed by at least two resistance mechanisms (P106S target-site mutation and amplification of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) gene). A phenotype-genotype association analysis was conducted to determine if the two GR mechanisms differ in their fitness costs and significance in conferring resistance. No fitness penalty was observed for the P106S substitution, while EPSPS amplification had a significant fitness cost (relative fitness of 1.12 and 0.72, respectively). EPSPS amplification and the P106S mutation did not fully account for glyphosate resistance in the population. The evolution of GR likely is a result of the interplay of different resistance mechanisms, with relative fitness of the mechanisms— both in the presence and absence of glyphosate—playing roles. The results from this novel study add to a growing body of evidence indicating that herbicide rotation is not an effective resistance management strategy because most herbicide resistances lack significant fitness costs.","This Dissertation was approved for publication on 2016-04-22 at 13:29.","DSpace SAF Submission Ingestion Package generated from Vireo submission #9342 on 2016-07-07 at 13:50:07","Made available in DSpace on 2016-07-07T20:27:48Z (GMT). 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