The Value of a Fungicide Application on Corn After a Hail Event

Trial Overview

  • Hail during the corn-growing season is a common10;occurrence on the Great Plains. Growers may consider applying a fungicide one10;week after a hail event as a way to help reduce the effects of hail damage on10;their corn crop.
  • Fungicides can help control foliar diseases like gray leaf spot, leaf blights, and rust which can occur without plant injury. Diseases that can occur after plant injury include Goss’s Wilt, common smut, and stalk rots, which are not effectively controlled by fungicides.

Research Objective

  • This study was established to evaluate if a10;foliar fungicide application following a mid-season hail event can increase the10;yield potential of a corn crop.
10;Location 10;
10;Soil Type 10;
10;Previous Crop 10;
10;Tillage Type 10;
10;Planting Date 10;
10;Harvest Date 10;
10;Potential Yield 10;
10;Planting Rate 10;
Gothenburg, NE
Silt Loam
Strip Till

10; Site Notes:10;

Understanding the Results

Figure 2. Average yield by corn growth stage and percent defoliation.
  • There was no significant interaction between corn10;growth stage, percent defoliation, or fungicide application.
  • There was no significant benefit of a fungicide10;application. Both the fungicide application and the no fungicide application10;treatments had an average yield of 167 bu/acre across all corn growth stages10;and defoliation treatments.
  • These results vary from the Gothenburg Learning10;Center report published in 2015 where an 11 bu/acre increase in yield potential10;was observed when a fungicide was applied.
  • This10;potentially was the result of dry weather conditions in Gothenburg in August with10;only 0.7 inches of precipitation recorded compared10;to 3.7 inches of precipitation in 2015. This environmental difference after10;fungicide application likely influenced results since more rainfall and higher10;humidity in 2015 was more conducive to foliar disease incidence and severity,10;possibly allowing fungicide application to result in increased yield potential.
  • The timing of the hail damage was significant10;with more yield loss observed on corn with 60% defoliation at the VT growth10;stage compared to corn with 60% defoliation at the R2 growth stage, or 104 to 136 bu/acre (LSD (0.1) = 13).
  • Hail damage during the VT growth stage occurs10;before flowering and pollination, which may lead to decreased yield potential10;as compared to the R2 growth stage when seed set has occurred. 

What Does This Mean for Your Farm

  • The benefit of a10;fungicide application on corn is independent as to whether or not the corn was10;injured by hail. 
  • Fields that10;experience wet and mild conditions during grain fill may benefit from a10;fungicide application. The benefit of a fungicide would be less likely if10;conditions were dry during grain fill. 
  • Severe hail10;damage at the VT growth stage consistently had the most negative effect on10;yield potential.