Natural enemies in Sorghum and Their Potential Role in Sugarcane Aphid Management Kristopher Giles Oklahoma State University Sorghum – Sugarcane Aphid Research Exchange Meeting Dallas, TX January 3 – 4, 2017

Introduction Large #’s of NE’s: Region specific How to integrate Predators Parasitoids Pathogen How to integrate impact?

Discussion Points / Issues Likelihood of NE impact Other invasive examples indicate? Aphid Biology-Ecology Natural Enemy Dynamics Sampling Natural Enemies NE thresholds Future Pest Status of SCA

Aphid Biology-Ecology Population doubling times (in days) at 23 °C (73 °F) Greenbug Sugarcane Aphid Susceptible 2.17 1.54 Resistant 2.77 3.30 *Real potential for top-down suppression on resistant lines!! Antixenosis / Antibiosis / Tolerance JP Michaud: KS116B (with 550610 res)

Natural Enemy Dynamics Susceptible Plant – Field – Landscape Resistant Plant – Field – Landscape Interaction with insecticides Life History Studies SCA Areawide Project Regional Landscape Dynamics Uniform Planting (Gulf State Regions) Early-and-Late Planting (Ex. Kansas) *Quantify pest/predator movement, dynamics and suppression "services"

Sampling NE’s and Thresholds Lindenmayer et al., Elliott et al.: Optimal sampling design for SCA threshold detection SCA sampling ≠ NE Sampling Should be developed during SCA studies: NE distribution(s) may be unique. Long-term Goal: NE Thresholds Dynamics and sampling data will allow for hypothesis testing and validation Royer et al. USDA-NIFA Grant

Key Learnings Absence of conclusive quantitative data, however, NE’s appear to have little impact on SCA, especially on susceptible varieties Detailed Studies on Natural Enemy Ecology and Sampling are needed if SCA remains sporadic to severe pest!

Next Steps Current Life-history and field level Investigator Studies Future SCA Areawide Project Results

Discussion