When to spray fungicide to protect your wheat crop and maximize yield

By Ty Bodeis  |  May 15, 2023

With some warmth and rain, the wheat in Michigan is growing fast. Soon the flag leaf and head will be emerging, and it will be time for fungicide applications. This will protect your wheat yield and ensure the highest quality. Head scab and leaf rust are a couple of the diseases that can affect the yield, and fungicides are a great management tool. To get the most disease protection for, timing the applications by identifying your growth stage is vital. 

Wheat relies on its flag leaf, which is the leaf just below the head, to intercept light and generate fuel to make around 90% of its yield. Therefore, protecting it from disease and keeping it healthy can make the difference in getting those top-end yields. Using the growth chart below, ideal application timing for the flag leaf is at Stage 9 to 10. This is when the flag leaf is just fully emerged so that you cover the entire leaf before disease has had the chance to develop on it. The next fungicide application comes at heading.  

Fusarium Head Scab is a major disease that most wheat growers typically manage in Michigan. It can rob yield and reduce the quality of the grain, meaning there are two ways for it to decrease income potential for your wheat. There are a few effective fungicides that can be used for head scab available on the market. In addition to choosing an effective fungicide, it is important to apply and time it right. The timing for Head Scab control is during flowering of the wheat. This happens after the head has fully emerged and has flowers on the head that look like small petals or flakes.  

Applications can be improved with higher water volumes; use nozzles that produce coarse and medium droplets. Extra coarse nozzles should be avoided. Using nozzles that direct the spray pattern on an angle in front and behind the boom can aid in proper coverage.  

DF Seeds varieties are screened for disease resistance regularly and their ratings are available at dfseeds.com. If you have any questions on your DF Seeds wheat variety contact your dealer or District Sales Manager. A great video explaining wheat diseases and application timings is available from MSU Extension.