Soybean rust

Area of impact: Leaves and pods

Description: Gray or brown crusty-looking spots occur first on the undersides of leaves. Pustules develop within the lesions and break open releasing spores. Lesions can also occur on pods and stems.

Pathogen involved: Phakopsora pachyrhizi and P. meibomiae (fungi)

Timing/Conditions: Can occur anytime but infection usually happens in the mid-to-late growing season. Prefers moderate temperatures, damp weather and high humidity.

Contributing factors: Fungi survive only on green living plants and are easily transmitted by wind.

Management practices: Scout lower soybean canopy weekly. Fungicides must be applied properly and at the right time.

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