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Corn Hybrid Response to Foliar Fungicides

Categories: GROWING, CORN
  • Making farm and field fungicide decisions can be complex.
  • To help the decision process, results from this study can help farmers understand hybrid susceptibility to disease and their response to fungicide.

There are many factors that go into making fungicide application decisions. Scouting and timely applications should always be the biggest drivers in the final decision. There are many levels of complexity beyond scouting that go into making farm-by-farm fungicide decisions. The Golden Harvest® Agronomy in Action research team conducts a yearly study that provides results to better understand the potential of individual hybrids to respond to fungicide treatment. Understanding hybrid susceptibility to a disease is extremely important in fields where disease pressure is highly predictable. It is more challenging to forecast an economic response within fields that rarely have noticeable disease presence.

Estimating Response with Low Disease Presence

Fungicide trials are established each year using Miravis® Neo fungicide applied at the R1 growth stage to evaluate individual hybrid response (Figure 1). Yield response varied greatly across hybrids and locations based on differing disease environments (Figure 2). The frequency and magnitude of individual hybrid response in lower disease environments was used to categorize hybrids into response categories of Best, Good, Fair and Poor.

Fungicide being applied to a Golden Harvest testing plot by a tractor in the field.
Figure 1. Fungicide being applied at R1; individual plots driven on were not harvested for yield
Map showing differences in fungicide responses across 2019-2021 hybrid screening in Golden Harvest trial locations.
Figure 2. Differences in fungicide response across 2019-2021 hybrid screening trial locations; the bubble size indicates the size of response at that site

Predicting Disease Risk for Each Field

Predicting disease can be difficult. However, timely fungicide applications prior to disease establishment almost always pay off. Selecting hybrids with good disease tolerance and utilizing foliar fungicides are important in areas with high disease risk. The following conditions can put fields at higher risk of disease development:

  • Continuous corn rotations
  • Reduced tillage fields with high residue levels where pathogens can overwinter
  • Extended periods of high humidity and leaf wetness that can favor disease development
  • Fields with history of standability issues
  • Observations of disease presence across multiple years
  • Early signs of disease infection on lower leaves

Benefits Beyond Yield – Stronger Stalks

In addition to disease control and potential yield response benefits, fungicide applications can also help improve standability at time of harvest. Consistent force was applied to multiple stalks, and plants subsiding to the pressure were recorded as a percentage of plants artificially lodging. Multiple hybrids treated with fungicide showed significant reduction of lodging (Graph 1).

Bar chart showing lodging reduction from Miravis Neo Application
Graph 1. Improved stalk quality from Miravis Neo fungicide application in 2020 at Clinton, IL

The data suggest that utilizing a foliar fungicide can:

  • Improve stalk integrity
  • Reduce stalk lodging
  • Decrease harvest losses
  • Reduce harvest time

An additional benefit observed with Miravis Neo is plants stay green longer, helping to extend photosynthesis and grain fill time later into the season. Also, water loss has been found to be reduced in short periods of drought, helping corn better tolerate stress.

Decision Process for Fungicide Application

  1. Select the best-suited hybrid for a field based on adaptability, agronomics and relative maturity
  2. Determine disease risk potential of field and use appropriate decision tool

Low Disease Fungicide Response

  • Utilize “Low Disease Fungicide Response” ratings to understand which hybrids have the best chance of responding in these conditions
  • Best or Good indicates the hybrid responded more often and at a greater magnitude
  • Fair or Poor indicates responses may be smaller and less consistent

High Disease Fungicide Response

  • Utilize “High Disease-Hybrid Susceptibility Rating” specific to disease of concern from chart below to understand which hybrids are more vulnerable to yield loss
  • Scout fields and make timely fungicide applications at sight of symptoms, first focusing on most susceptible hybrids. Always follow product labels.
Table of Golden Harvest Hybrids rated based on low disease fungicide response.

To learn more about factors to consider when deciding on corn fungicide application, watch this video.

All photos are either the property of Syngenta or used with permission.

Syngenta hereby disclaims any liability for Third Party websites referenced herein.

Performance assessments are based upon results or analysis of public information, field observations and/or internal Syngenta evaluations.

Product performance assumes disease presence.

© 2022 Syngenta. Important: Always read and follow label instructions. Some products may not be registered for sale or use in all states or counties. Please check with your local extension service to ensure registration status. AAtrex 4L, AAtrex Nine-O, Acuron, Agri-Flex, Agri-Mek 0.15EC, Agri-Mek SC, Avicta 500FS, Avicta Complete Beans 500, Avicta Complete Corn 250, Avicta Duo Corn, Avicta Duo 250 Corn, Avicta Duo COT202, Avicta Duo Cotton, Besiege, Bicep II Magnum, Bicep II Magnum FC, Bicep Lite II Magnum, Callisto Xtra, Cyclone SL 2.0, Denim, Endigo ZC, Endigo ZCX, Epi-Mek 0.15EC, Expert, Force, Force 3G, Force CS, Force 6.5G, Force Evo, Gramoxone SL, Gramoxone SL 2.0, Gramoxone SL 3.0, Karate, Karate with Zeon Technology, Lamcap, Lamcap II, Lamdec, Lexar EZ, Lumax EZ, Medal II ATZ, Minecto Pro, Proclaim, Tavium Plus VaporGrip Technology, Voliam Xpress and Warrior II with Zeon Technology are Restricted Use Pesticides.

Some seed treatment offers are separately registered products applied to the seed as a combined slurry. Always read individual product labels and treater instructions before combining and applying component products.

Always read individual product labels and treater instructions before combining and applying component products.

Important: Always read and follow label and bag tag instructions; only those labeled as tolerant to glufosinate may be sprayed with glufosinate ammonium-based herbicides. LibertyLink®, Liberty® and the Water Droplet logo are registered trademarks of BASF. HERCULEX® and the HERCULEX Shield are trademarks of Corteva Agriscience LLC. HERCULEX Insect Protection technology by Corteva Agriscience LLC. Under federal and local laws, only dicamba-containing herbicides registered for use on dicamba-tolerant varieties may be applied. See product labels for details and tank mix partners. Golden Harvest® and NK® soybean varieties are protected under granted or pending U.S. variety patents and other intellectual property rights, regardless of the trait(s) within the seed. The Enlist E3® soybean, LibertyLink®, LibertyLink® GT27®, Roundup Ready 2 Xtend®, Roundup Ready 2 Yield® and XtendFlex® soybean traits may be protected under numerous United States patents. It is unlawful to save soybeans containing these traits for planting or transfer to others for use as a planting seed. Only dicamba formulations that employ VaporGrip® Technology are approved for use with Roundup Ready 2 Xtend® and XtendFlex® soybeans. Only 2,4-D choline formulations with Colex-D® Technology are approved for use with Enlist E3® soybeans. The trademarks or service marks displayed or otherwise used herein are the property of a Syngenta Group Company. ENLIST E3® soybean technology is jointly developed with Corteva Agriscience LLC and M.S. Technologies, L.L.C. The ENLIST trait and ENLIST Weed Control System are technologies owned and developed by Corteva Agriscience LLC. ENLIST® and ENLIST E3® are trademarks of Corteva Agriscience LLC. GT27® is a trademark of M.S. Technologies, L.L.C. and BASF. Roundup Ready 2 Xtend® , Roundup Ready 2 Yield®, XtendFlex®, VaporGrip® and YieldGard VT Pro® are registered trademarks used under license from the Bayer Group.

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