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Is Your Corn Primed For A Late Fungicide Application?

Jun 18, 2020


Is Your Corn Primed for a Late Fungicide Application?
While the window for late fungicide applications has come and gone for early planted corn , producers who planted late still might have an opportunity to boost yield potential with a fungicide treatment applied between V15 and tassel – whether a disease like northern corn leaf blight is of concern , or not.
 
“Most growers seeded in one of two planting windows this spring , so we have a wide range of maturity in the Mississippi Delta this season ,” explains Kevin Harper , WinField® United Performance Optimization District Sales Manager in northern Louisiana. “Corn is anywhere from V10 to R3 , so those later crops can still benefit from a fungicide – especially if they have a high or moderate Response to Fungicide score.”
 
It wasn’t that long ago that you had to base your fungicide decision purely on scouting observations. If disease pressure was noted in the area , you’d call your applicator and hope he could fly over your fields as soon as possible. If disease wasn’t an issue , you were off the hook…or so you thought.
 
“We’ve since found that in addition to protecting plants from disease , fungicides contribute to plant health by improving efficiencies within the plant ,” Harper says. “Research performed in recent years at Answer Plot® locations throughout the nation has found that some hybrids respond better to a late fungicide application than others. Hybrids with a low Response to Fungicide (RTF) see little to no increase in yield potential , but hybrids with moderate to high RTF scores – those are the ones where a late fungicide can provide a good return on investment. This is especially the case when your crop is already looking good and you’re anticipating strong yields.”
 
In 2019 , WinField United performed RTF research trials on 240 different hybrids at Answer Plot locations across the country. Each was replicated 200 times , and trials took place in all environments , with high and low disease pressure alike. When all the results were tabulated , the corn plants that received a fungicide application at R1 saw a positive response of 16.1 bu/A over the untreated check.*
 
“We have two CROPLAN® corn hybrids with high-to-moderate RTF scores that are popular in and around the Mississippi Delta – CP5678VT2P and CP6027VT2P/RIB ,” Harper says. “If you planted either of those , I recommend targeting them with a late fungicide application. Some agronomists advise making that application right at tassel , while I personally like to get it out there and into the plant at V15. Either way , make sure you include MasterLock® adjuvant in your tank to reduce spray drift and improve deposition into the plants.”
 
MasterLock® combines the proven drift control and deposition of InterLock® adjuvant with DropTight additive , an exclusive non-ionic surfactant that specifically enhances the performance of fungicide applications. Harper recommends adding 6.4 oz/A of MasterLock to your fungicide tank mix in a carrier solution of at least 5 gal water/A.
 
Finally , Harper encourages you to take full advantage of this late application by having plant tissue samples evaluated by NutriSolutions® tissue analysis prior to spraying. The tool will identify whether any nutrient deficiencies are present in your crop , and recommend the appropriate MAX-IN® plant micronutrients and rates to add to your fungicide tank mix to correct the problem.
 
There are a number of high quality products suited for late fungicide applications. For assistance in selecting the right fungicide and rates for your fields , consult your local GreenPoint AG specialist.
 
 
* National average difference between fungicide application at R1 and untreated control. 2019 Answer Plot program data.

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