How to Manage Pests
UC Pest Management Guidelines
Pink rot appears as a decay of tubers that usually begins at or near the stem end of potatoes in the field or through eyes of potatoes in storage. Infected tissue becomes somewhat rubbery but not discolored. When an infected tuber is cut, the rotted portion is delineated by a dark line at its margin. With exposure to air, the surface of the decay turns a salmon pink color, which later turns to brown and then finally black. Roots and lower stems may also rot, causing a wilt and early dying of plants. The spread of pink rot may continue in storage.
Pink rot is a major problem of potatoes. The pathogen survives for long periods in the soil and becomes active when the soil is saturated with water.
Pink rot is most frequently seen in mature plants approaching harvest. It is much worse when saturated soil is accompanied by warm temperatures. Avoid prolonged saturation of soils during irrigation, provide good drainage, and avoid harvesting wet tubers. Maintain good airflow, avoid the accumulation of moisture on tubers, and maintain low temperatures during storage because the fungus is inactive below 40°F. In areas where pink rot is a problem, treat 2 and 4 weeks before harvest.
UC IPM Pest Management Guidelines: Potato