This spring, cool nights followed by warm, humid days have created ideal conditions for wheat leaf diseases to emerge early and spread quickly. For Ontario growers aiming to protect yield and maintain grain quality, strategic fungicide applications will be essential.
Key Diseases to Watch
- Stripe Rust: Moves quickly in cool, moist conditions. Early infections can rapidly escalate and impact the flag leaf if not contained.
- Powdery Mildew: Tends to develop in thick, lush canopies and can limit photosynthesis well before heading.
- Leaf Rust: Appears later in the season but can still reduce grain fill if left unmanaged.
Strategic Fungicide Timing
- T1 (herbicide timing): This is your first line of defense. If early signs of disease are present, consider a fungicide tank mix with your herbicide pass.
- T2 (flag leaf stage): The most important window for protecting yield. The flag leaf contributes more than half of final grain weight, so prioritize clean coverage with a fungicide that offers both protection and control.
- T3 (flowering): If Fusarium head blight risk is high, this timing can help reduce DON levels and preserve grain marketability.
Best Practices for Effective Control
- Scout frequently to detect issues early, especially in high-risk varieties.
- Choose the right product with multiple modes of action to manage resistance and extend protection.
- Spray with precision—angled nozzles, proper water volume, and calm conditions make a difference in coverage and efficacy.
Get Advice That’s Field-Tested
At Sylvite Agri-Services, our agronomists are in the field every day, monitoring disease trends and helping you make the right call for your operation. From selecting fungicides to optimizing your spray strategy, we’re here to support your success.