Fungicide Guidelines for your Wheat

-Sandra Wick, Crop Production Agent

Well, the million dollar question is, "Should I spray a fungicide on my wheat?"

The answer is, "It depends!"  That may seem like NOT an answer, but it really does depend on many factors including the weather forecast, variety susceptibility and the stage of the wheat.

Stripe Rust is what I found about 3 weeks ago in every county of the Post Rock District.   There could also be some leaf rust out there as well.   However, until we received the moisture, the rust was just pretty much sitting there and not spreading.  However, the forecast looks like it may be favorable for stripe and leaf rust development.  Looking at the 10 day forecast, we could have cool temperatures and chances for moisture.  These are the conditions that stripe rust likes and thrives!

Scouting is the key to first determine if your wheat is infected with stripe rust or leaf rust.  It seems to be pretty variety dependent so look at the "KSU Variety Disease and Insect Ratings for 2015".  Here is a link for you:  http://bit.ly/1NGavz2.   Everest and Armour have the highest susceptibility rating of the more common wheat varieties that are planted.   If you don't find rust, then don't spray especially with the price of what wheat is at this time.  But if you are finding the rust pustules one or two leaves below the flag leaf and cool, moist conditions are in the forecast, spraying may be warranted.  

So when do I spray?  First and foremost is the growth stage of your wheat.  For the fungicide to last or have residual through grain filling, the flag leaf should be fully extended. The stage of growth around the district is all over the board.  We were ahead of schedule, but now have caught up some, so the only way to know is to get out in your field.  I have attached a GREAT publication from TAMU on "Wheat Stages of Growth".  Your primary goal of the fungicide application is to protect the flag leaf which contributes a very high percentage to grain fill.  This should allow sufficient time for the fungicide to last through grain filling.

So what do I spray?  There are many good options out there that do an equally effective job, so it comes down to price.  Another big question is using generics?  Of course the generics would be cheaper and more economical with our price situation.  According to KSU research, there is no significant difference in the effectiveness of products with identical active ingredients.  In other words, generic fungicides are equally effective when used at the same rates as other products with the same active ingredient.  Most fungicides have a 21 day residual in the field for protection against the rust diseases.  KSU has an excellent publication, "Foliar Fungicide Efficacy Ratings for Wheat Disease Management 2016" that rates several different options. Here is the link for you:  http://bit.ly/1pqEaGn

 So weather will certainly play a KEY role in what develops! Please let me know what you are finding out in the fields!  Remember scout your fields first and look at your stage of growth and any rust infection.