The fungus is on the tubers or in the soil and causes rough scabby spots on tubers. Try to maintain the soil pH below 5.7 and use resistant varieties. Avoid adding alkaline materials such as manure, wood ashes, or lime to soil used for growing potatoes. There is no chemical control for the disease.
The leaves show small, irregular, dark brown spots. The spots enlarge and have target like markings. Use sprays of copper(1) or Chlorothalonil(0).
The leaves or stems have dark irregular dead areas. Infected tubers may rot in storage. The plants may be killed early. The disease is favored by cool, moist weather. Use sprays of copper(1), or Chlorothalonil(0).
Symptoms are upward rolling of the leaves and stunted plants. This disease is one of several spread by aphids. There is no chemical control.
The disease causes mottled and curled leaves and stunted plants. This disease is spread by aphids. There is no chemical control.
Wilt and Dry Rot
Symptoms are yellow leaves and drooping plants. Brown rings form in stems and tubers and infected tubers rot in storage. No chemical control is listed.