Quantifying the Contribution of Seed Blended Refugia in Field Corn to Helicoverpa zea (Lepidoptera: Noctuidae) Populations

• Published in: Journal of economic entomology Vol. 114; no. 4; pp. 1771 - 1778
• Main Authors: Towles, T. B., Buntin, G. D., Catchot, A. L., Gore, J., Cook, D. R., Caprio, M. A., Daves, C.
• Format: Journal Article
• Language: English
• Published: US Entomological Society of America 01-08-2021; Oxford University Press
• Subjects: Agricultural ecosystems; Bacillus thuringiensis; Butterflies & moths; Corn; Genetic engineering; Genetically modified crops; grower compliance; Growing season; Helicoverpa zea; INSECTICIDE RESISTANCE AND RESISTANCE MANAGEMENT; Insecticides; moth emergence; Pesticide resistance; Pests; refuge; Refugia; Risk reduction; Seeds; Transgenic plants; Vegetables; North Carolina; grower compliance; moth emergence; refuge
• ISSN: 0022-0493; 1938-291X
• DOI: 10.1093/jee/toab097

Helicoverpa zea (Boddie), a pest of cotton that also occurs in field corn, is commonly controlled through the use of foliar-applied insecticides or transgenic crops expressing Bacillus thuringiensis (Berliner) (Bt) genes. To minimize the risk of Bt resistance in pest populations, refuge systems have been implemented for sustainable agroecosystem management. Historically, structured refuge compliance among growers has been low, leading to the commercialization of seed blended refugia. To test the viability of seed blended refugia in southern U.S. field corn, field studies were conducted in Mississippi and Georgia during 2016, 2017, and 2018 growing seasons. To quantify adult H. zea emergence from structured (non-Bt corn) and seed blended refuge options, emergence traps were utilized. Kernel damage among seed blended refuge and structured refuge corn ears were recorded and compared. The timing of moth emergence was recorded. When compared to a structured refuge, H. zea adult moth emergence from seed blended refugia did not significantly differ. Kernel damage of non-Bt plants in the seed blended treatments was not significantly different than non-Bt plants in the structured refuge treatments. Moth emergence timing was not significantly delayed between the structured refuge and seed blended refuge treatments. Results of this study suggest that a seed blended refuge may provide an effective insecticide resistance management alternative for H. zea in areas where structured refuge compliance is low.