Poster # 114

Olanrewaju Shittu ¹, Mladen Cucak ², Felipe Dalla Lana ³, Wanderson Bucker Moraes ⁴, Pierce A. Paul ⁵, Denis A. Shah ⁶, Erick D. De Wolf ⁶, and Paul D. Esker ¹.
1. Penn State University, Department of Plant Pathology and Environmental Microbiology, State College, Pennsylvania.
2. Syngenta Crop Protection, Crop Protection Development, Basel, Switzerland.
3. Louisiana State University, The LSU AgCentre, Baton Rouge, Louisiana.
4. Corteva Agriscience, Crop Protection Operation Center, Indianapolis, Indiana.
5. The Ohio State University, Department of Plant Pathology, Wooster, Ohio.
6. Kansas State University, Department of Plant Pathology, Manhattan, Kansas.
Corresponding Author: Olanrewaju Shittu, oms5169@psu.edu

Olanrewaju Shittu

Fusarium head blight (FHB) threatens Pennsylvania's wheat industry, causing economic losses due to reduced grain quality, yield, and mycotoxin contamination. The yield loss caused by the disease in Pennsylvania is estimated to be $19 million between 2018 and 2022. Managing this devastating disease requires accurate risk assessment that can aid farmers in making informed decisions regarding disease prevention and control strategies. In this study, we present the validation of the Fusarium Head Blight Weather-Based Risk Tool in the context of Pennsylvania, a region with a notable wheat industry. The FHB Risk Tool is a web-based forecasting system that predicts FHB epidemic risk (>10% FHB index) and guides in-season fungicide application decisions. The FHB Risk Tool uses weather variables such as temperature and humidity, which are known to impact FHB development, along with different levels of wheat resistance to FHB. This research aims to validate the FHB Risk Tool's predictive accuracy in Pennsylvania for the years 2018, 2020-2023. Flowering dates, FHB incidence, and severity data were collected from various research trials at the Russell E. Larson Agricultural Research Center at Rock Springs (40.710208, -77.950024) and the Southeast Agricultural Research and Extension Center at Manheim (40.118769, -76.427366). We hypothesized that there is no significant difference between the forecasted FHB risk and the actual FHB incidence and severity in these locations for the years 2018 and 2020 - 2023. Preliminary results show that the FHB tool forecasted risk for 2021 and 2023 aligned with the observed FHB index at both locations. However, the tool predicted high FHB risk for 2018 and 2020, but the observed FHB disease index was low at both locations, below the 10% threshold. Meanwhile, in 2022, the tool predicted a high risk, but this was observed only in Manheim. The difference between the FHB risk forecasted and the FHB index observed in the field may be due to factors not considered by the tool, such as rotation history, residue management, and the three small-grain production zones in Pennsylvania. These results are important to guiding extension educational programs focused on the integrated management of wheat diseases. We expect this research will encourage stakeholders to adopt the FHB Risk Tool as a reliable resource for making informed, in-season decisions in their wheat production strategies.