Location: Peanut and Small Grains Research Unit
Project Number: 3070-22000-017-009-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Sep 14, 2016
End Date: Sep 14, 2022
Objective:
The objectives of this project are to monitor development of sugarcane aphid populations in sorghum and host grasses throughout the year to provide data to validate synoptic model for sugarcane aphid migration and to define geographic overwintering potential; and to evaluate potential for sugarcane aphid biocontrol by existing natural enemies.
Approach:
Daily migratory flights of sugarcane aphid (SCA) will be simulated using the NOAA Air Resources Laboratory (ARL) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model (HYSPLIT PC version 4.9) (Draxler 1999; Draxler and Hess 1997, 1998; Draxler and Rolph 2013) following the methods of Westbrook et al. (2016). The 40-km resolution EDAS (Eta Data Assimilation System) data set will provide input to HYSPLIT model simulations of sugarcane aphid migration. The proportion of migrants will be estimated based on local host suitability, which will be associated with crop growth stage and presence of alternative plant hosts, and direct measurements of sugarcane aphid populations of winged individuals. Daily availability of migrant aphids at source locations will be defined for universally invoking simulated 12-h emigration flights (1200 to 0000 Universal Coordinated Time [UTC]). For daily flights, the emigrant proportion of the aphid population will be directly transferred to an emissions (i.e., emigratory) source file as input to the HYSPLIT model simulations. Resident and migratory aphids will contribute to infestation only within the spatial extent and suitability of susceptible host plants. The number of winged aphids that develop during a specific time period will be pooled into a single cohort for comparison with scouting data. Seasonal patterns of simulated abundance of aphids originating from source areas will be mapped. Predictions will be validated by ongoing monitoring in AWPM demonstration areas and intensive ground-truthing at locations where model predictions indicate sugarcane aphid deposition. The focus of biocontrol research will be to quantify natural enemy densities and SCA mortality for resistant and susceptible sorghum for the purpose of demonstrating effects of the SCA AWPM program on biocontrol.
