Effect of Plant Population on Foliar Fungicide Response in Corn


  • Determine yield response of corn to foliar fungicide application at the VT growth stage.
  • Evaluate plant population by fungicide interaction.

Study Description

Locations: 17 on farm-trials across northeast Colorado and eastern Nebraska, including both irrigated and non-irrigated locations
Replicates:   1 per location
  Pioneer® Brand  
  Corn Products:
4 per location (8 total)
3 or 4 per location (7 total populations) 
• 18,000   • 22,000   • 26,000   • 30,000
• 34,000   • 38,000 • 42,000  
Plot Layout:
Chart: Plot layout


  • Weather conditions in 2013 were more conducive to disease development than the previous 2 years.
  • Across all locations, hybrids and seeding rates, the average yield response to fungicide application was 6.4 bu/acre compared to untreated corn.


Chart: Average Yield Response to VT Fungicide
  • 15 out of 17 locations had a positive yield response to fungicide application
    • 8 locations had a yield response greater than 6 bu/acre.


Chart: Fungicide Response by Seeding Rate
  • Yield response to VT fungicide application was greater at higher plant populations.
    • Stalk lodging was less than 5% at the higher plant populations regardless of whether fungicide was applied.
Chart: Yield Response of VT Application vs. Untreated

Pioneer® brand products are provided subject to the terms and conditions of purchase which are part of the labeling and purchase documents. 2013 data are based on average of all comparisons made in 17 locations through Dec. 27, 2013. Multi-year and multi-location is a better predictor of future performance. Do not use these or any other data from a limited number of trials as a significant factor in product selection. Product responses are variable and subject to a variety of environmental, disease, and pest pressures. Individual results may vary.