Northern corn leaf blight (NCLB) is one of the more economically significant foliar diseases in corn production, capable of reducing yield potential by limiting photosynthetic activity during grain fill. While infection can impact carbohydrate production and kernel development, the greatest concern is loss of upper canopy leaf function during critical reproductive stages.
How Northern Corn Leaf Blight Develops
The pathogen (Exserohilum turcicum) survives in infected corn residue and can persist between growing seasons. Spores are spread primarily through wind and rain splash, moving from infected residue onto lower leaves before progressing upward through the canopy.
From there, lesions can expand rapidly under favorable environmental conditions—especially when prolonged periods of moisture are present. This makes NCLB not just an isolated leaf issue, but one that can significantly impact overall plant productivity during grain fill.
When and Where It Shows Up
Disease development is favored by moderate temperatures (65–80°F), high humidity, and extended periods of leaf wetness. Fields with significant corn residue are often at greater risk, as the pathogen overwinters in infected plant material.
Infection becomes most economically damaging when lesions reach the upper canopy prior to or shortly after tasseling. At that point, reduced photosynthetic area directly impacts carbohydrate production and kernel development during grain fill. Extended periods of humid, wet weather can accelerate disease progression and increase severity across the field.
What We’re Seeing in the Field
Across 17,766 acres, data shows an increase in NCLB risk year over year:
- High Risk: 46.5% (2024) → 65.9% (2025)
- Moderate Risk: 16.2% (2024) → 5.3% (2025)
- Low Risk: 37.3% (2024) → 28.8% (2025)
With more acres shifting into high-risk categories, northern corn leaf blight continues to be an increasing concern for protecting upper canopy health and preserving yield potential through grain fill.
Our Solution
Managing northern corn leaf blight starts with understanding when environmental conditions are favorable and identifying fields with elevated risk before disease reaches the upper canopy.
Xyway LFR + Forcivo™ fungicide provides a proactive approach—helping protect plants during key periods of disease development while supporting overall plant health and grain fill performance throughout the season.
