Location: Biological Control of Insects Research
Project Number: 5070-22000-037-005-T
Project Type: Trust Fund Cooperative Agreement
Start Date: Jul 1, 2015
End Date: Jun 30, 2019
Objective:
1. Identify strains of entomopathogenic nematodes that are most infectious of western corn rootworm resistant to Cry proteins, specifically, Cry3Bb1. Compare infectiousness of Heterorhabditis bacteriophora, H. megidis, Steinernema carpocapsae, and S. feltiae in resistant and susceptible rootworm.
2. Identify those entomopathogenic nematode strains that are most responsive to herbivore-induced plant volatile organic compounds, specifically a sesquiterpene. Measure responses of nematodes to sesquiterpene using below-ground olfactometer bioassays.
3. Enhance overwintering capability and persistence of entomopathogenic nematodes. Measure survival in laboratory (vary temperature and moisture) and field settings (with and without cover crop). Select for enhanced cold and desiccation tolerance in individual nematode species and mixtures of species.
4. Deliver improved resistance management system targeting Cry3Bb-resistant western corn rootworm using entomopathogenic nematodes with improved attraction to sesquiterpene and persistence. Demonstrate a combination of nematode species and soil amendment for control of resistant rootworms.
Approach:
Test field and laboratory strains of entomopathogenic nematodes for infectivity of western corn rootworm resistant to Cry proteins. Test the infective strains for: (a) responsiveness to plant-released herbivore-induced volatile organic compounds and (b) survival after exposure to high and low temperature extremes and desiccation. Determine whether individual strains or mixtures of strains are more efficacious for controlling Bt resistant rootworms in field settings that compare mono-crop, crop-rotation and cover crop practices.
