This ongoing project investigates the hidden spread of Huanglongbing (HLB) during the asymptomatic phase, motivated by the work of Lee et al. (2014/2015). Unlike direct plant-to-plant transmission systems, HLB spreads indirectly through the movement of the Asian citrus psyllid, creating complex spatial dynamics before visible symptoms appear.
The goal of this project is to develop a spatial and network-based modeling framework that captures vector-mediated transmission, short latency periods, and grove geometry. The model incorporates weighted migration patterns, flush-level infectiousness, and intervention scenarios to understand how early management strategies may delay large-scale infection.
Key components:
Vector mediated transmission through psyllid migration
Spatially weighted network structure (within-row vs between-row movement)
Latent period dynamics and asymptomatic spread
Evaluation of early intervention strategies
This project develops a spatially explicit stochastic SEIRB network model to study the spread and management of Frogeye Leaf Spot (FLS) in soybean fields. The framework integrates environmental reservoirs, plant-to-plant transmission, and realistic field geometry to evaluate disease control strategies.
Using Approximate Bayesian Computation Sequential Monte Carlo (ABC-SMC), the model is calibrated against observed epidemic data to explore parameter sensitivity, intervention timing, and roguing strategies.
Highlights:
Spatial plant network with environmental inoculum dynamics
Calibration using ABC-SMC inference
Analysis of targeted vs random intervention strategies
Simulation of realistic field scale epidemics