The 2018 growing season may be off to a great start in most areas of the Corn Belt, but one Mycogen expert says variable weather and heavy rain makes scouting for foliar diseases even more important. And another reason growers should consider a foliar fungicide plan to protect their corn silage crop through the hot, humid summer months.
“The use of a fungicide application on corn silage can preserve the integrity of the plant and, ultimately, prevent a loss of yield due to foliar pathogens such as northern corn leaf blight, gray leaf spot or eyespot,” says Jon Erickson, Mycogen Seeds commercial agronomist.
A loss in tonnage yield not only will impact storage values for the year to come but also can hurt return on investment for corn silage in 2018. To get the most out of their corn silage investment, Erickson suggests growers take these steps against foliar diseases:
- Review field history. Regularly scout your fields and determine the locations most susceptible to disease. Many foliar pathogens survive in corn residue on soil surfaces, and risk for disease increases in fields planted to corn year after year.
- Record weather history. Increased rain and humidity create the perfect environment for foliar diseases to thrive. Add in continuous cloud cover and extended dew periods of at least 12 hours, and diseases will spread rapidly.
- Examine fields before tasseling. Start scouting to detect and identify any diseases present and determine the severity. For gray leaf spot or northern corn leaf blight, you can estimate the severity by counting the number of infected plants as a percentage of the total number of plants assessed.
- Plan for fungicide application. While you assess your field, if at least 50 percent of your plants show signs of foliar diseases, consider using a fungicide to protect from further loss of quality and yield. Work with your local agronomist to factor in environment conditions and plant development to get the most out of your fungicide investments.
- Follow label directions. Apply your fungicide at the correct rate for the growth stage and adhere to any restrictions on spray quantities and harvest dates.
Finally Erickson says growers should consult their local agronomist to scout fields, review disease pressures, and build an action plan to manage foliar diseases to grow a high-quality corn silage crop this season.
