Location: Corn Insects and Crop Genetics Research
Project Number: 5030-30400-001-000-D
Project Type: In-House Appropriated
Start Date: Oct 18, 2025
End Date: Oct 17, 2030
Objective:
Objective 1: Determine the genetic and genomic architecture of arthropod resistance to control tactics, with a focus on corn earworm, European corn borer, and corn rootworm.
Sub-objective 1.A. Determine genomic architecture of phenotypic traits within and among reproductive and ecological variants of key pest insects that affect their control.
Sub-objective 1.B. Identify genomic regions that contribute to phenotypic resistance in pests of the corn agroecosystem.
Objective 2: Improve knowledge of ecological and behavioral factors of the maize insect pests the corn earworm and European corn borer impact abundance and spread of resistance to control tactics.
Sub-objective 2.A. Determine how insect movement and exposures impact the potential for development of resistance to insecticidal agents, including Bt proteins.
Sub-objective 2.B. Determine response and survival of insect genotypes across insecticidal exposures.
Objective 3: Release new germplasm with resistance to maize pests such as corn earworm and fall armyworm and provide associative tools and information for breeders.
Sub-objective 3.A. Develop and characterize fall armyworm leaf feeding resistance, improve phenotyping methodology, and publicly release inbred lines of maize.
Sub-objective 3.B. Examine DHLs for resistance to silk feeding CEW, identify contributing metabolite and alleles, and publicly release inbred lines of maize.
Approach:
Farmers are challenged with managing multiple arthropod pests that accumulated diverse physiological and ecological adaptations to the agroecosystem. Pest insects resistant to widely used control strategies, such as insecticidal treatments and cultural control practices, often arise, spread across populations, and cause crop injury that results in lost yield and profits. The range of interactions among organismal, ecological, and molecular factors that contribute to the development and subsequent spread of adaptive phenotypes across the agricultural landscape are not fully understood. Such deficiencies have contributed to the reoccurring loss of efficacy among control measures, despite preventative measures enacted through IRM strategies. Maize is the largest grain crop in the U.S. and is highly integrated into our food, feed, biofuel and industrial supply chains. Developing knowledge and tools to understand vulnerabilities of current IRM strategies, stem the spread of resistant insects, and bolster complementary IPM approaches will strengthen the stability, profitability and security of maize production, and bolster domestic economic prosperity.
This project plan will address pertinent knowledge gaps in the biological, ecological, genetic and genomic determinants of key traits and provide tools to increase the effectiveness of IRM as outlined in the ARS 2025-2030 Action Plan. Objectives 1 and 2 will target the key biological, genetic and/or ecological traits of invasive CEW and endemic ECB and WCR that facilitate the development or spread of adapted genotypes. While not an exhaustive list of all variation found within arthropod pests, this approach will target the traits that pose the most imminent and economically significant threats to maize production in the U.S. Outcomes will generate knowledge for evaluating the efficacy of current IRM strategies and tools to detect and monitor adaptive insect genotypes in the field. Objective 3 develops maize that resists and/or tolerates insect herbivory, providing novel IPM options that could be pyramided with Bt proteins to enhance the efficacy of IRM. Cohesion among these objectives will 1) identify the biological and ecological factors that contribute to the development of insecticide resistance, 2) develop methods to detect and monitor resistant insects in the field, and 3) develop novel IPM approaches to manage resistant insects.