Stochastic dynamic population model for northern corn rootworm (Coleoptera: Chrysomelidae)

Area of Science:

• Ecology
• Entomology
• Population Dynamics

Background:

• Northern corn rootworm (Diabrotica barberi) is a significant agricultural pest.
• Existing models often lack comprehensive life cycle simulation and stochasticity.

Purpose of the Study:

• To develop a stochastic dynamic population model for the complete life cycle of the northern corn rootworm.
• To investigate factors influencing population dynamics, including temperature, density dependence, and resource availability.

Main Methods:

• A stochastic model incorporating temperature-dependent development, age-dependent advancement, and density-dependent larval survival was developed.
• Regional corn phenology was modeled to assess the impact of dispersal on adult mortality.
• Stochastic daily weather, egg hatch, and larval survival were simulated.

Main Results:

• Deterministic simulations indicated population collapse without adult mortality reduction.
• Corn pollen availability, influenced by regional corn phenology, is essential for sustaining adult populations.
• Stochastic simulations confirmed model behavior under varying environmental conditions.

Conclusions:

• The developed model provides a robust framework for understanding northern corn rootworm population dynamics.
• Management strategies should consider the role of adult resources, such as corn pollen, in pest population regulation.