1 / 11

Southern Rust of Corn: Outline

Southern Rust of Corn: Outline. Distinguishing common rust vs. southern rust Southern rust is potentially much more destructive Guidelines to consider in fungicide decisions Monitor for stalk strength. Uredia of southern rust (upper leaf surface view).

tavi
Télécharger la présentation

Southern Rust of Corn: Outline

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Southern Rust of Corn: Outline • Distinguishing common rust vs. southern rust • Southern rust is potentially much more destructive • Guidelines to consider in fungicide decisions • Monitor for stalk strength

  2. Uredia of southern rust (upper leaf surface view)

  3. Southern rust (right side) vs. common rust (left) Upper leaf surface Lower leaf surface Images by Alison Robertson, Iowa State University

  4. Leaf desiccated by southern rust Courtesy Greg Henson, McLean Co. Extension

  5. “Green islands” of southern rust

  6. Teliaof southern rust Courtesy Greg Henson, McLean Co. Extension

  7. “Puccinia pathways” for P. polysora ? http://lib.utexas.edu/maps/americas/north_america_ref_2007.pdf

  8. U.S. corn: susceptible to low levels of resistance Image at left courtesy Bob Kemereit, Univ. Georgia

  9. Pace of disease progress under worst-case conditions • 5-6 weeks: From undetected to substantial damage • 2-3 weeks: Can cause substantial damage, if disease is present… • …More or less throughout the field (even at very low levels) • …In all levels of the canopy (lower, middle, and upper)

  10. Days after mid-silk • R2 (blister stage): 10-14 days • R3 (milk stage): 18-22 days • R4 (dough stage): 24-28 days • R5 (dent stage): 35-42 days • R6 (physiological maturity): 55-65 days http://www.agronext.iastate.edu/corn/production/management/growth/yield.html

  11. Watch for loss of stalk strength

More Related