Assume I’m on board with early season application of Stratego YLD. At harvest, I do a side-by-side yield comparison between treated and untreated fields and there’s no difference. Does that prove there’s no need for an early season fungicide application?
A lot of variables go into corn production. We have to consider that a fungicide doesn’t fix all the deficiencies a plant or field or crop might have. A fungicide, especially one containing a strobilurin component like Stratego YLD, can help the plant utilize limited resources better but it can’t make up for true shortages. You’re not going to see as much value from the fungicide if there’s something much larger limiting your field.
Strobilurin-containing fungicides tend to help on both ends of the spectrum where disease or resource limitations have an effect. If resources such as nitrogen or moisture are limited, or disease pressure lowers the yield potential for the field, fungicides can address the disease part of the equation while assisting the plants to more efficiently utilize the limited resources.
At the other extreme are the “race horse” hybrids, which might have the genetics for higher yields, but often are prone to susceptibility to diseases, or the genetic potential may outstrip the resources present in the field. These fungicides improve the likelihood that the yield reflects the genetics.
With that said, there are some years when everything is near perfect for that particular hybrid and it experiences few stresses. Disease pressure is low, and moisture, nutrients and other factors are abundant. In those situations, the fungicide benefit can be limited. However, we can’t always plan on having a year like that, so it’s better to plan on helping the plants to be as productive as possible.
In fact, replicated field trial data demonstrate that a fungicide application will pay for itself more than 80 percent of the time, or about 8 out of every 10 years.