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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Potato > Deformed tuber

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Potato > Tuber > Deformed tuber

1 of 2
  • Black Scurf/Rhizoctonia Canker 1
  • Black Scurf/Rhizoctonia Canker 2
  • Black Scurf/Rhizoctonia Canker 3

Black Scurf/Rhizoctonia Canker
Rhizoctonia solani

  • Tuber production is low, tubers may be small and deformed
  • Underground stems and roots have brown, sunken dry spots
  • Small hard black spots stick to the skin of the tuber like dirt that won't wash off
  • In severe cases, small green tubers form on the stem above ground
  • Stem has a white to gray flaky growth just above the soil line.
  • Delayed or not emergence, have few stems, and poor growth
  • Most problematic in cool wet soils
  • More information on Black Scurf/Rhizoctonia Canker...
2 of 2
  • Corky Ring Spot 1
  • Corky Ring Spot 2
  • Corky Ring Spot 3

Corky Ring Spot
Tobacco Rattle Virus

  • Potato tubers can be cracked and malformed if infections comes in early
  • Brown rings and arcs form on the skin and in the flesh of tubers
  • Leaves may have no symptoms or have yellow rings, spots and arcs
  • Stems may be mottled green and yellow
  • More information on Corky Ring Spot...

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