Optimizing Early-season Pest Control in Corn: Untangling the Contributions of Neonicotinoid Seed Treatments, In-furrow Pyrethroids, and Bt Hybrids

Project Overview

Project Type: Graduate Student
Funds awarded in 2020: $14,961.00
Projected End Date: 07/31/2022
Grant Recipient: University of Maryland
Region: Northeast
State: Maryland
Graduate Student:
Faculty Advisor:
Dr. Kelly Hamby
University of Maryland College Park


  • Agronomic: corn


  • Pest Management: biological control, chemical control, field monitoring/scouting, integrated pest management

    Proposal abstract:

    Corn growers have several options for at-planting pest control, including neonicotinoid seed treatments (NSTs), pyrethroids that can be applied in the planting furrow, and corn hybrids with plant incorporated protectants sourced from Bacillus thuringiensis bacteria (Bt); growers may also use all three together. Because these treatments target similar pests, using multiple products can be redundant. Targeting insect control and using the most effective product could reduce insecticide use, thereby increasing environmental sustainability and decreasing input costs. Insecticide treatments can also disrupt biological control. For example, NSTs can reduce slug predator populations in soybeans, causing economically damaging outbreaks of slugs. Because slugs are a concern in the Mid-Atlantic and difficult to control, it is important to determine if at-planting insecticides similarly impact biological control of slugs in corn. Lower corn prices may increase adoption of less expensive non-Bt corn, which has a unique pest complex for which at-planting applications must also be optimized. To improve pest management decision making in corn, we will conduct separate field studies using Bt and non-Bt hybrids and evaluate the impacts of NSTs and in-furrow pyrethroids on pest control by measuring pest pressure and damage to seedlings. Because treatments may disrupt slug biological control, we will also measure slug abundance, slug predator abundance, and slug predator activity. Finally, we will compare yield and quantify ear pest pressure. Results will be disseminated through extension presentations and publications, enabling growers to plan targeted early-season pest control programs for more financially and environmentally sustainable corn production.

    Project objectives from proposal:

    My goal is to provide information to help growers to tailor early season pest control tactics to their needs, increasing sustainability and profitability. In order to achieve this, my specific objectives are to:

    (1) Determine how NSTs and in-furrow pyrethroids affect pest pressure and damage when used against pest complexes in three Maryland growing regions using separate in Bt and non-Bt corn fields.

    (2) Determine the impact of NSTs and in-furrow pyrethroids on biological control of slugs by measuring slug damage, slug predator abundance, and predation rates on slugs in three Maryland growing regions

    (3) Determine the impacts of NSTs and in-furrow pyrethroids on yield and evaluate late season ear and stand damage in three Maryland growing regions using separate in Bt and non-Bt corn fields.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.