Verticillium wilt becomes evident when lower leaves on the vine turn yellow and wither. Wilt causes early senescence of plants in heavily infested fields. The fungus persists in soil for long periods. Infection is favored by cool weather, but symptom development is favored by high temperatures. The fungus interferes with water transport in the stems, so injury is most severe during periods of hot weather when plants are stressed for water.
Some cultivars are more tolerant than others.
Rotate out of potatoes and other susceptible crops for 2 to 3 years. Cereals, grasses, and legumes are good rotation crops. The Regents of the University of California. All rights reserved. For noncommercial purposes only, any Web site may link directly to this page or photo file.