By Jamie Martin
As corn crops move through critical development stages, growers are assessing whether fungicide applications will provide economic and agronomic benefits. Experts recommend focusing on disease pressure and crop growth stage before making treatment decisions.
The ideal fungicide application period generally falls between tasseling (VT/R1) and the milk stage (R3). Protecting the ear leaf during this window can help maintain grain-fill potential and support strong yields.
Southern Rust remains one of the diseases being monitored most closely. Current reports indicate that confirmed cases are limited to southern regions. Since the fungus does not typically survive winter conditions across most corn-growing areas, annual infections depend on spores moving north from southern locations. At present, disease pressure remains low, but growers should continue monitoring weather patterns and crop conditions.
Tar Spot has also been detected at low levels in some fields. Most infections have been found in lower portions of the crop canopy. Warm temperatures may slow disease development temporarily, but cooler conditions later in the season could increase the risk of spreading.
Additional corn diseases, including Gray Leaf Spot and Northern Corn Leaf Blight, have also been reported. Although infections are mostly confined to lower leaves, continued scouting remains important to detect potential movement toward the upper canopy and ear leaf.
Economic considerations remain a major factor in fungicide decisions. Specialists advise farmers to assess disease severity, crop revenue expectations, and application expenses before proceeding. Applications made before disease threats emerge may not generate positive returns.
Technology is also expanding management options. Recent field evaluations suggest drone-based fungicide applications can offer disease suppression and yield preservation like traditional aerial treatments. This emerging approach may provide growers with greater flexibility when application timing becomes critical.
Photo Credit: gettyimages-dszc
Categories: National