Managing Foliar Wheat Diseases on a Budget

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1 Managing Foliar Wheat Diseases on a Budget Bob Hunger Extension Wheat Pathologist

2 Wheat Foliar Diseases Leaf rust (Dr. J. Edwards) Tan spot Powdery mildew Stripe rust (Dr. P. Lipps) Septoria/Stagonospora leaf & glume blotch

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4 Longevity of Control Following Wheat Foliar Fungicide Application Wheat Chickasha; ; Stripe rust; left 4.5 reps received fungicide Photo credit Brian Arnall

5 Chickasha Standard vs. Intensive Wheat Management Comparison Grain yield (bu/ac) Test weight (lb/bu) Standard Intensive Difference Standard Intensive Difference Pete Ruby Lee Endurance Doublestop CL Billings Gallagher Deliver Centerfield Mean of all 50 varieties + lines From: Oklahoma Small Grains Variety Performance Tests , J. Edwards, et al.

6 Wheat Disease Control following Fungicide Application 2015 primarily leaf rust Disease Severity (%) PM=powdery mildew LR=leaf rust Fungicides applied on 10 Apr (GS 10) PM rated on 29 Apr LR read on 12 May (32DAA) and 18 May (38DAA) PM LR32DAA LR38 DAA

7 Yield and Test Weight Impact following Wheat Foliar Fungicide Application Yield (bu/a) & TW (lb/bu) Yield TW Average yield increase = 32% Average TW increase = 7%

8 2014 Wheat Disease Control using Fungicides Yield (bu/a) & test weight (lb/bu) For Yield & TW no differences between fungicides Yield TW Fungicides Priaxor FB TwinLine applied on 19 Mar (GS 6) FB TwinLine on 25 Apr (GS 10.3) All other fungicides applied on 25 Apr (GS 10.3) No ratable disease observed in trial

9 Return on Fungicide Use North Carolina/Virginia

10 Return on Fungicide Use North Carolina/Virginia

11 Return on Fungicide Use North Carolina/Virginia

12 Average Benefit on Fungicide Use North Carolina Routine application of any of the three fungicide classes to wheat fields every year was a losing proposition. But the average longterm net returns from only applying fungicides when disease was over threshold were excellent; ranging from $9 to $13 per acre.

13 Wheat Foliar Fungicides in Oklahoma (Not a complete listing) Rate PHI A Product (oz/a) (days/gs) TRIAZOLE (FRAC Group 3) Tilt Syngenta Folicur Bayer CropScience 4 30 Prosaro Bayer CropScience STROBILURIN (FRAC Group 11) Headline BASF Evito Arysta LifeScience Aproach - DuPont /10.5 TRIAZOLE + STROBI (FRAC Groups ) Quilt Xcel - Syngenta Stratego YLD Bayer CropScience 4 35 TwinLine BASF /10.5 Aproach Prima DuPont Fortix Arysta LS/Cheminova Generics are available for Tilt and Folicur This information is provided only as a guide. It is the responsibility of the pesticide applicator by law to read and follow all current label directions. No endorsement is intended for products listed, nor is criticism meant for products not listed. SDH INHIBITOR (FRAC Group 7) Vertisan DuPont (forage/hay)/ SDH INHIBITOR + STROBI (FRAC Groups ) Priaxor BASF A PHI = pre-harvest interval; number of days required between last application & harvest

14 Economics of Wheat Foliar Fungicide Use Current Report CR % X 30 bu/a X $4.00/bu $8.00/A = +$4.00/A 10% X 40 bu/a X $4.00/bu $8.00/A = +$8.00/A 10% X 40 bu/a X $4.00/bu $16.00/A = $0.00/A 10% X 60 bu/a X $4.00/bu $16.00/A = +$8.00/A

15 Fungicide Observations/Conclusions Foliar fungicides will protect yield that is present at the time of application better to spray a little early than a little late Apply with ground rig or aerial key is to apply in a timely fashion Not only protects yield, but also results in higher test weight/quality Consider early application (GS 6-7) if have lots of wheat residue and see tan spot, powdery mildew, and/or Septoria early, or see numerous stripe rust hot spots Know the reaction of your planted varieties to foliar diseases, scout your fields, and monitor what is happening to the south