Poster # 102

Luan Castegnera, Erick DeWolf, and Kelsey Andersen Onofre
1. Department of Plant Pathology, Kansas State University, Manhattan, KS, USA

Castegnera, Luan

luancastegnera@ksu.edu

Fusarium head blight (FHB), caused by Fusarium graminearium, it is one of the most economically significant fungal diseases, causing substantial losses to producers in various regions of the world. Integrated management of wheat scab combines the use of resistant cultivars and the application of fungicides at the beginning of flowering (Feekes 10.5.1). We hypothesize is that, for FHB management, a second fungicide application performed four days after the initial treatment at Feekes 10.5.1 may result in greater disease control efficacy. The experiments were conducted in Manhattan and Ottawa during the 2024-25 season. The variety ‘Green Hammer’, classified as susceptible to FHB, was used in this study. Plots were inoculated with F. graminearum- infested corn spawn. The experimental fields were irrigated using a sprinkler system. Treatments followed the USWBSI MGMT-CP Uniform Fungicide Trial (UFT) protocol and consisted of 1) Non-treated control, 2) Prosaro® 6.5 fl oz/A at flowering, 3) Miravis® Era 10.3 fl oz/A at flowering, 4) Miravis Ace 13.7 fl oz/A at flowering, 5) Prosaro Pro 10.3 fl oz/A at flowering, 6) Sphaerex® 7.3 fl oz/A at flowering, 7) Miravis Ace 13.7 fl oz/A followed by Prosaro pro 10.3 fl oz/A, 8) Miravis Ace 13.7 fl oz/A followed by Sphaerex 7.3 fl oz/A, 9) Miravis Ace 13.7 fl oz/A followed by TebuStar® 4 fl oz/A, 10) TebuStar 4 fl oz/A followed by Miravis Ace 13.7 fl oz/A. FHB severity was evaluated as the average symptomatic area of heads infected out of 90 total heads per plot. Data collected were subjected to mixed-model analysis of variance, and means were compared using Tukey’s Honest Significance Difference (HSD) at a 5% level of significance. Fungicide applications had no significant effect on yield or test weight in Manhattan, although the non-treated check generally yielded lower than the plots that received a fungicide treatment. Similarly, in Ottawa, no significant difference was observed among treatments for yield; however, a significant effect was observed for test weight (𝘱 = 0.0032), with higher values observed for treatments 7 and 8. Significant differences were observed in disease-related variables at both locations. In Manhattan, treatments had a significant effect on disease index (𝘱 < 0.0001), FDK (𝘱 < 0.0001), and DON (𝘱 < 0.0001). Similar results were observed in Ottawa. Overall, a consistent reduction in disease levels was observed with fungicide use, particularly with sequential applications, with treatments 7 and 8 showing the greatest level of disease control.

© Copyright 2025 by individual authors. All rights reserved. No part of this abstract or paper publication may be reproduced without prior permission from the applicable author(s).