{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T18:26:08Z","timestamp":1775413568014,"version":"3.50.1"},"reference-count":38,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T00:00:00Z","timestamp":1775347200000},"content-version":"vor","delay-in-days":35,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Agricultural Biotechnology Stewardship Technical Committee"},{"name":"Hatch Multistate project NC246 project funds","award":["GA-1009397"],"award-info":[{"award-number":["GA-1009397"]}]},{"DOI":"10.13039\/100005825","name":"U.S. Department of Agriculture National Institute of Food and Agriculture","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100005825","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,3,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>The corn earworm, Helicoverpa zea (Boddie), is a major lepidopteran pest of corn (Zea mays L.) in the United States and is widely managed using transgenic corn hybrids expressing Bacillus thuringiensis (Berliner) (Bt) proteins. Seed-blend refuges, in which Bt and non-Bt seeds are mixed in fixed proportions, have been widely adopted as a convenient insect resistance management (IRM) strategy. However, concerns remain about their efficiency in producing susceptible moths compared to a structured block refuge. To evaluate this, five field experiments were conducted across Texas and Georgia during 2020 to 2021 to compare adult H. zea emergence from non-Bt refuges configured as structured 100% non-Bt blocks or as 80:20 Bt\/non-Bt seed blends. Adult production was quantified using two approaches: emergence cages that captured pupal-to-adult survival and screen bags that confined larvae on individual ears. Both methods yielded comparable estimates of adult H. zea emergence. Across all locations and years, seed-blend plots consistently produced fewer moths than expected based on the 20% refuge proportion, yielding 61% to 91% of the adults produced from structured refuges. Screen bag assays similarly showed reduced larval and pupal recovery from seed-blend ears. Non-Bt ears from seed-blend plots did not consistently differ from structured refuges in larval feeding intensity. Findings from this study indicate that seed-blend refuges may underperform in producing susceptible moths and may not consistently function as an effective standalone refuge strategy.<\/jats:p>","DOI":"10.1093\/jisesa\/ieag030","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T12:50:55Z","timestamp":1773838255000},"source":"Crossref","is-referenced-by-count":0,"title":["Evaluation of structured and seed-blend refuges for corn earworm (Lepidoptera: Noctuidae) using emergence cages and screen-bagged ear methods"],"prefix":"10.1093","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5063-1618","authenticated-orcid":false,"given":"Suhas S","family":"Vyavhare","sequence":"first","affiliation":[{"name":"Texas A&M AgriLife Research and Extension Center Department of Entomology, , Lubbock, TX,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1999-6477","authenticated-orcid":false,"given":"G David","family":"Buntin","sequence":"additional","affiliation":[{"name":"Department of Entomology, University of Georgia , Griffin, GA,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joni L","family":"Blount","sequence":"additional","affiliation":[{"name":"Bayer CropScience , Creve Coeur, MO,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Matthew","family":"Carroll","sequence":"additional","affiliation":[{"name":"Bayer CropScience , Creve Coeur, MO,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pat","family":"Porter","sequence":"additional","affiliation":[{"name":"Texas A&M AgriLife Research and Extension Center Department of Entomology, , Lubbock, TX,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"286","published-online":{"date-parts":[[2026,4,5]]},"reference":[{"key":"2026040513025990900_ieag030-B1","author":"ABSTC","year":"2016"},{"key":"2026040513025990900_ieag030-B2","doi-asserted-by":"publisher","first-page":"914","DOI":"10.3390\/insects15120914","article-title":"Bt trait efficacy against corn earworm, helicoverpa zea, (lepidoptera: Noctuidae) for preserving grain yield and reducing mycotoxin contamination of field corn","volume":"15","author":"Barton","year":"2024","journal-title":"Insects"},{"key":"2026040513025990900_ieag030-B3","doi-asserted-by":"publisher","first-page":"1845","DOI":"10.1093\/jee\/toz062","article-title":"Susceptibility of corn earworm (lepidoptera: Noctuidae) to cry1a. 105 and cry2ab2 in North and South Carolina","volume":"112","author":"Bilbo","year":"2019","journal-title":"J. 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