Ask an Agronomist
Should I Use A Corn Fungicide?
Nov 08, 2010
Question: What do you recommend regarding the use of fungicides in corn?
Answer: "You must know what fungicide to apply for each disease, and when to apply it,” says Ken Ferrie, Farm Journal Agronomist. "It's not a matter of simply applying whatever product your supplier happens to sell.”
Some fungicides are preventive in nature, which means they must be applied before a lot of disease damage has occurred. Others are curative, which means they can be applied later.
"But all fungicides work best if they are applied at the early onset of disease,” says University of Illinois Extension Plant Pathologist Carl Bradley
"Keep in mind which leaves you are trying to protect the most—the leaves closest to the ear,” he continues. "A preventive application can still be effective if lower leaves have the disease but the important leaves are still disease-free.
"In my studies, tassel emergence or slightly after seems to be the best timing for corn fungicides,” Bradley adds. "This year (2010 season), applications very early in the season—at the V5 stage or so—are being talked about; but, in general, disease pressure is very low, or even absent, at that time. Unfortunately, there seems to be very little data available, either from companies or universities, on these early fungicide applications to corn.”
Bradley and Ferrie are conducting fungicide research in corn. Stay tuned this winter as Farm Journal will continue to address the important topic of fungicide use.
Check out this information to evaluate fungicide use in corn.
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