Managing Foliar Wheat Diseases on a Budgetnotill.okstate.edu/presentations/2016-presentation/2016HungerManage... · wheat residue and see tan spot, powdery mildew, and/or Septoria

Dr. Bob HungerState Extension Wheat Pathologist

405‐744‐[email protected]

Department of Entomology & Plant Pathology

127 Noble Research CtrOklahoma State University

Managing Foliar Wheat Diseases on a Budget

Bob HungerExtension Wheat PathologistOklahoma State University





Wheat Foliar Diseases

Leaf rust (Dr. J. Edwards)

Powdery mildew

Tan spot

Septoria/Stagonosporaleaf & glume blotchStripe rust (Dr. P. Lipps)









Longevity of Control Following Wheat Foliar Fungicide Application - 2015

Wheat trial @ Chickasha; 4‐24‐2015; Stripe rust; left 4.5 reps

received fungicidePhoto credit – Brian Arnall





Grain yield (bu/ac) Test weight (lb/bu)Standard Intensive Difference Standard Intensive Difference

Pete 10 78 68 ‐‐‐‐ 59.7 ‐‐‐‐Ruby Lee 25 64 39 44.7 53.9 9.2Endurance 37 64 26 48.9 54.4 5.6Doublestop CL + 41 60 19 53.7 52.0 ‐1.7Billings 59 78 19 56.1 58.8 2.7Gallagher 58 75 17 55.7 58.0 2.3Deliver 52 64 12 53.9 55.0 1.1Centerfield 47 59 11 51.7 55.0 3.3Mean of all 50 varieties + lines

45 70 25 52.7 56.0 3.3

Chickasha Standard vs. Intensive Wheat Management Comparison

From: Oklahoma Small Grains Variety Performance Tests 2014-2015, J. Edwards, et al.





0

20

40

60

80

100

120

PMLR32DAALR38 DAAD

isease Severity

(%)

PM=p

owde

ry m

ildew

LR=

leaf ru

st

Wheat Disease Control following Fungicide Application – 2015 – primarily leaf rust

‐Fungicides applied on 10‐Apr (GS 10)‐PM rated on 29‐Apr‐LR read on 12‐May (32DAA) and 18‐May (38DAA)





0102030405060708090100

YieldTW

Yield and Test Weight Impact following Wheat Foliar Fungicide Application - 2015

Yield (bu/A) & TW (lb/bu

)

• Average yield increase = 32%

• Average TW increase = 7%

50515253545556575859

YieldTW

2014 Wheat Disease Control using Fungicides Yield (bu/A) & te

st

weight (lb/bu)

For Yield & TW – no differences between fungicides

Fungicides‐Priaxor FB TwinLine applied on 19‐Mar (GS 6) FB TwinLine on25‐Apr (GS 10.3)‐All other fungicides applied on 25‐Apr (GS 10.3)‐No ratable disease observed in trial





Return on Fungicide Use – North Carolina/Virginia















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 long‐term net returns from only applying fungicides when disease was over threshold were excellent; ranging from $9 to $13 per acre. ”





Wheat Foliar Fungicides in Oklahoma(Not a complete listing)

Rate PHIA

Product (oz/A) (days/GS)TRIAZOLE (FRAC Group 3)

Tilt – Syngenta 4 10.5Folicur – Bayer CropScience 4 30Prosaro – Bayer CropScience 6.5-8.2 30

STROBILURIN (FRAC Group 11)Headline – BASF 6-9 10.5Evito – Arysta LifeScience 2-4 40Aproach - DuPont 6-12 45/10.5

TRIAZOLE + STROBI (FRAC Groups 3 + 11)Quilt Xcel - Syngenta 10.5-14 10.5Stratego YLD – Bayer CropScience 4 35TwinLine – BASF 7-9 30/10.5Aproach Prima – DuPont 3.4-6.8 45Fortix – Arysta LS/Cheminova 4-6 40

SDH INHIBITOR (FRAC Group 7)Vertisan – DuPont 10-24 0 (forage/hay)/10.5.1

SDH INHIBITOR + STROBI (FRAC Groups 7 + 11)Priaxor – BASF 4-8 10.5

___________________________________________________________APHI = pre-harvest interval; number of days required between last application & harvest

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.





Economics of Wheat Foliar Fungicide Use Current Report CR 7668

10% X 30 bu/A X $4.00/bu ‐ $8.00/A = +$4.00/A10% X 40 bu/A X $4.00/bu ‐ $8.00/A = +$8.00/A10% X 40 bu/A X $4.00/bu ‐ $16.00/A = $0.00/A10% X 60 bu/A X $4.00/bu ‐ $16.00/A = +$8.00/A





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

Documents

Managing Foliar Wheat Diseases on a Budgetnotill.okstate.edu/presentations/2016-presentation/2016HungerManage... · wheat residue and see tan spot, powdery mildew, and/or Septoria