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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Snap bean > Discoloration on stems

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Snap bean > Stem > Discoloration on stems

1 of 3
  • White Mold 1
  • White Mold 2
  • White Mold 3

White Mold
Sclerotinia sclerotiorum

  • Infected stems dry out and turn light brown
  • Leaves, stems and pods first develop water-soaked lesions
  • A white, cottony fungal growth develops on leaves, stems and pods
  • Leaves yellow and fall off
  • Plant wilts, and may eventually die
  • Hard black irregular to oval shaped sclerotia (fungal structures) form within and on infected plant parts
  • More information on White Mold...
2 of 3
  • Bean Rust 1
  • Bean Rust 2
  • Bean Rust 3

Bean Rust
Uromyces appendiculatus

  • Pods and stems develop reddish-brown raised pustules
  • Leaves develop reddish-brown, raised pustules surrounded by a yellow halo
  • Powdery brown spores can be seen when spots are rubbed with a white tissue
  • Severe infections cause leaves to brown, dry, and drop from the plant
  • More information on Bean Rust...
3 of 3
  • Anthracnose 1
  • Anthracnose 2
  • Anthracnose 3

Colletotrichum lindemuthianum

  • Seedling stem has black lesions
  • Dark brown to black, sunken oval spots on pods
  • Black, sunken streaks or ovals on petioles and stems
  • Random dark brown to black lines develop along leaf veins
  • More information on Anthracnose...

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