Optimizing Egg Recovery From Wild Northern Corn Rootworm Beetles (Coleoptera: Chrysomelidae).

Area of Science:

• Agricultural Entomology
• Insect Pest Management
• Behavioral Ecology

Background:

• The northern corn rootworm (Diabrotica barberi) is a significant pest in the U.S. Corn Belt.
• Previous attempts to collect eggs from wild populations using established methods for other rootworm species have failed due to poor oviposition.

Purpose of the Study:

• To develop an efficient and robust system for collecting eggs from wild northern corn rootworm (Diabrotica barberi) populations.
• To evaluate the impact of oviposition media and female density on egg collection success.

Main Methods:

• Evaluated four oviposition media in choice tests with varying female densities (2016).
• Conducted non-choice assays with single females in small plastic boxes.
• Assessed cumulative egg production per female across different densities (2017-2018).

Main Results:

• Oviposition was poor in initial large cage trials (1.2 eggs/female).
• Small plastic boxes with appropriate media yielded up to 108 eggs/female.
• Total egg production per box increased with higher female densities, with no significant decrease in per-female production up to 10 females/box.

Conclusions:

• A novel and effective system for collecting northern corn rootworm (Diabrotica barberi) eggs has been established.
• This method allows for the collection of large numbers of eggs from wild populations, facilitating further research and pest management strategies.