An implicit approach to model plant infestation by insect pests

Area of Science:

• Ecology
• Mathematical Biology
• Agricultural Science

Background:

• Spatial heterogeneity significantly impacts population dynamics.
• Understanding host-parasitoid interactions is crucial for pest management.
• Existing models often lack the spatial detail needed for complex environments like greenhouses.

Purpose of the Study:

• To develop and apply a novel flux-based model for aphid-parasitoid systems in spatially structured environments.
• To analyze the influence of spatial factors and parasitoid functional responses on pest population dynamics.
• To assess the model's utility for biological control strategy development in greenhouses.

Main Methods:

• A flux-based model using partial differential equations, ordinary differential equations, and delay-differential equations.
• Application to the Aphis gossypii (aphid) and Lysiphlebus testaceipes (parasitoid) system in a melon greenhouse.
• Numerical simulations and sensitivity analysis to explore parameter impacts.

Main Results:

• Aphid populations were slightly higher with Type III functional response compared to Type II.
• Population dynamics were sensitive to initial host distribution and parasitoid release density.
• Key parameters influencing dynamics included parasitoid delay and pest growth rate.

Conclusions:

• The flux-based model provides a synthetic and effective approach for predicting pest-parasitoid dynamics in greenhouses.
• The model offers a valuable tool for testing biological control strategies and managing crops across multiple greenhouses.
• Initial conditions and parasitoid behavior are critical factors for successful pest management.