Wheat Management Mike Roegge University of Illinois Extension Adams/Brown Unit With special thanks to Dr. Carl Bradley, Dr. Steve Ebelhar, Dr. Eric Adee

Fusarium Head Blight – Scab Caused by the fungus: Fusarium graminearum Bleached heads Healthy spikelets remain green Same organism causes Fusarium stalk rot in corn

Conditions favorable for Fusarium head blight Flowering thru kernel development –Prolonged periods of high humidity –Moderate temperatures = 75 to 85°F –Prolonged wet periods

Scab Incidence in Wheat, Monmouth, (1997, 98, )

Proline Fungicide Full registration last year on wheat (2007) Prothioconazole is the active ingredient (triazole) Applied at 4.3 to 5.7 fl oz/A Has been evaluated in Illinois wheat scab fungicide trials (applied at early anthesis – Feekes 10.51)

What’s available for scab control in 2008? Proline (prothioconazole) – fully registered in 2007 –Apply at early anthesis (Feeke’s ) Never spray a fungicide that contains a strobilurin (Headline, Quadris, Quilt, Stratego) component at this stage! –Vomitoxin (DON) levels can increase

Monmouth, IL Eric Adee, Univ. IL

Monmouth, IL Eric Adee, Univ. IL

Urbana Wheat Fungicide Trial – 2007 FungicideScab (%)DON (ppm) Test wt (lb/bu) Yield (bu/A) Untreated fl oz/A 30**

Monmouth Wheat Fungicide Trial – 2007 FungicideScab (%)DON (ppm) Test wt (lb/bu) Yield (bu/A) Untreated fl oz/A Data courtesy Eric Adee, Univ. of Illinois

Summary of University of Illinois trials with Proline Can consistently reduce scab disease levels and DON levels in harvested grain Not enough “high disease pressure” trials to always observe significant yield differences

Wheat Scab Management Infects wheat when flowering Requires high humidity/rain for spore production and infection Favored by mild temperatures (65-86 o F) Scab Risk Tool:

What about control of diseases other than scab? Other diseases- Leaf and glume blotch, tan spot, rusts Can control other diseases at the timing (scab timing), but may be able to have better control of lead diseases at an earlier timing……..flag leaf to early heading (9 to 10.1) Protect the flag leaf!

Spring Scouting for Diseases Protect the Flag Leaf Septoria Leaf Blotch Powdery Mildew Rust Protect the Head

Managing Leaf, Glume, Rust Diseases Crop rotation –Stubble-borne diseases Resistant varieties Fungicides –Some control with “scab” timing –Better control earlier……..protect the flag leaf!

Fungicides for leaf, glume, rust diseases Many available Triazoles – Proline, Tilt (Curative) Strobilurins – Headline, Quadris (Protectant) Mixtures – Stratego, Quilt

2003 to 2007 Illinois Summary UIUC and SIUC trials Data from Belleville, Brownstown, Carbondale, Dixon Springs, Urbana. Applications made at or near flag leaf emergence. UIUC trials = S. Ebelhar and C. Bradley; SIUC trials = B. Young Overall average = 3 bu/A over the untreated

Fungicides for leaf, glume, and rust diseases Bigger benefits observed on more susceptible varieties Timing = flag leaf emergence may provide the best protection of flag leaf- label restrictions on most to restrict application to: 1) before flowering or 2) before flag leaf finished emerging Application at flowering - will get some protection of leaf diseases, but don’t apply a strobilurin product at this stage Scout at flag leaf emergence and thereafter, idea is to protect flag leaf (80% of fill?)

Spray or Not? 1. Does the field appear to have adequate yield potential 2. Has there been rainy weather or heavy dews the week going into flag leaf emergence and is this weather expected to continue? 3. How susceptible is the variety to leaf diseases (rust, septoria, etc.) 4. The Cereal Rust Bulletin ( is a good way to find out if rusts are headed north. If some of the rusts are approaching and the weather has been favorable for disease, then this should also be another level of consideration for a fungicide. Dr. Carl Bradley,