Asian Rust & Soybean Aphid Map
Click Here to view the Asian Rust Tracking Map

Click Hereto view the Soybean Aphid Tracking Map
(Second drop down menu on right - choose Soybean Aphid)

Identify Soybean Rust
How To Identify Soybean Rust
One of the challenges of dealing with soybean rust is that the disease is hard to identify. Early symptoms appear as yellowish mosaic discoloration on the upper surfaces of older leaves. As the disease progresses, infected leaves turn yellow, and brown or reddish pustules appear, generally on the bottom surface of the leaf.

  • Starts deep in lower canopy
  • Yellow mosaic on older leaves
  • Brown, stippled appearance
  • Leaves turn completely yellow
  • Brown or reddish pustules appear

Under a 20x hand lens, the pustule can be seen to be raised, and have a pore on top, rather than a fissure. It lookslike a little volcano. Soybean rust pustules also lack the yellowish halo associated with bacterial pustule.