Corn Seed Products Yield Response to an Aerial Fungicide Application - DEKALB®

Trial Overview

  • Corn disease infestations can decrease leaf and stalk quality which may negatively affect yield potential. A broad-spectrum fungicide applied around VT (tasseling) to R1 (silking) growth stages may reduce the effect of diseases on yield potential.
  • The effect of a fungicide application on corn yield can be influenced by several factors including seed product disease tolerance, existing disease pressure, timing of application, and environmental conditions.

Research Objective

  • The objective of this study was to evaluate DEKALB® brand blend products’ yield response to an aerial fungicide application at VT growth stage.
Soil Type
Previous Crop
Tillage Type
Planting Date
Harvest Date
Potential Yield
Planting Rate
Goodland, KS
Silt loam
220 bu/acre
26,000 seeds/acre

Site Notes:

Each seed product had two treatments:  1) No fungicide and 2) Quilt Xcel® Fungicide applied at 12 fl oz/acre on July 14, 2017 at VT growth stage.Eight DEKALB® brand blend products were tested in small plots with three replications at two (untreated and treated) locations at opposite ends of the same field.Disease incidence was as follows: southern rust (Puccinia polysora) that was initially observed at the V12 (12 leaf collars) growth stage – moderate infestation; Goss’s wilt and bacterial leaf streak – observed to be present.



Understanding the Results

  • Economic benefit was determined assuming $2.95/bu corn commodity price and a fungicide product and aerial application cost of $30.00/acre.
  • The application of Quilt Xcel® Fungicide increased yield in all products tested and the average yield increase was 36.6 bu/acre.
  • All corn products exhibited a positive economic benefit from a Quilt Xcel® Fungicide application.
  • DKC55-20RIB and DKC60-88RIB brand blends had the highest positive yield response from Quilt Xcel® Fungicide application.
  • DKC60-67RIB and DKC63-21RIB brand blends had the lowest positive yield response from Quilt Xcel® Fungicide application.

What Does This Mean for Your Farm

  • Fungicides can protect yield when applied correctly and timely.
  • The benefits of a fungicide treatment at the appropriate growth stage may have a greater effect when applied to moderate to susceptible (disease ratings) seed products under high disease pressure conditions.
  • Scouting plans should be in place prior to tasseling for fields with susceptible genetics, that are continuously corn-on-corn, or have a history of disease.
  • Yield potential, corn growth stage, disease risk, cost of fungicide, and corn commodity price should all be considered when deciding whether to spray a fungicide.
  • Farmers can further minimize the risk of disease-induced yield loss by selecting a resistant to moderately-resistant seed product when planting in disease-prone regions.
  • The data is a result of a single site, replicated study conducted in Goodland, Kansas and is intended to represent the seed products’ response under 2017 conditions for this region. Results may vary depending on disease presence, environmental conditions, and other factors.
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