Submitted to: National Soybean Rust Symposium
Publication Type: Abstract only
Publication Acceptance Date: 6/1/2006
Publication Date: 7/1/2006
Citation: Mueller, T.A., Bradley, C.A., Chesrown, C.D., Kemerait, R.C., Wright, D.L., Marois, J.J., Miles, M.R., Hartman, G.L. 2006. Evaluation of Fungicides and Fungicide Timing for the Control of Phakopsora pachyrhizi in the United States. National Soybean Rust Symposium. Plant Disease. 90(7):970. Interpretive Summary:
Technical Abstract: Timing of fungicide applications is a critical component in managing soybean rust and if used effectively, may reduce the number of applications needed for economic benefit. The objectives of these experiments were to evaluate the affects of different timings of fungicide applications on soybean rust severity and yields. Trials were conducted in two locations with soybean rust (Quincy, FL and Attapulgus, GA) and two locations without soybean rust (Urbana, IL and Fargo, ND). Treatments in each field included applications with: triazole (Folicur), strobilurin (Headline), or triazole-strobilurin combinations (Quilt or Headline + Folicur) at either (i) growth stage (GS) R1, (ii) GS R3, (iii) GS R5, (iv) GS R1 and R3, (v) GS R3 and R5, (vi) GS R1, R3, and R5, or (vii) not sprayed. The fungicides were applied with a backpack sprayer with TeeJet XR11002 tips at 40 PSI. In locations with soybean rust all treatments had significantly less disease severity. Preliminary analysis indicates that there were yield differences at some of the locations.