Skip to main content
APS Plant Health 2025 Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.

POSTERS: Population Biology Genetics I

P-561 - Differential response of Fusarium graminearum isolates to DMI fungicides.

Monday, August 4, 2025
4:30 PM - 5:15 PM HST
Location: Exhibit Hall 3

    Presenting Author(s)

  • SG

    Sandhya Gopisetty, PhD

    Graduate Research Assistant
    Kansas State University
    Manhattan, Kansas, United States

    • Author(s)

  • CT

    Christopher Toomajian

    Associate Professor, Department of Plant Pathology
    Kansas State University
    Manhattan, Kansas, United States

  • SC

    Sumit Chowdhury

    Graduate Research Assistant
    Kansas State University
    Manhattan, Kansas, United States

Abstract Text: Fusarium Head Blight (FHB) caused by a fungal pathogen Fusarium graminearum is one of the major constraints to wheat production in the United States due to its reduced yield and mycotoxin contamination. Intensive application of fungicides on cereal crops like wheat has led to the development of resistance in many fungal pathogens that infect them. Historically, populations of Fusarium graminearum have been treated largely as homogeneous at the level of management and resistance breeding. However, this clashes with documented variation in populations in terms of pathogenic traits like fungicide sensitivity, toxin production etc. This work aimed at determining the variation in sensitivity of the F. graminearum NA2 population to tebuconazole and propiconazole and identifying the genetic basis of phenotypic variation to provide targets for disease management. Sensitivity of 150 F. graminearum isolates towards the two demethylation inhibitor (DMI) fungicides were tested using a flat bottom 96-well plate assay. Absorbance readings were taken before incubation, and at 5 and 7 days at 405 ŋm. Effective concentration 50 (EC50) values were computed using R packages. We use standard statistical methods for detecting associations between genetic variants derived from whole-genome sequencing and pathogen traits. Using genome wide association studies (GWAS), we aim to identify the genetic basis of variability in fungicide sensitivity. We anticipate our results will aid in developing strategies to manage FHB outbreaks and will suggest targets for pathogen control.