Symptoms and Signs
Plants with bacterial crown rot may be stunted. During periods of high temperatures, the leaves may wilt. In advanced stages of the disease, plants may collapse entirely. New leaves in the center of plants may fail to expand, becoming brown and dry. Crown and tap root tissues become soft and rotted, and turn brown or black. Infected crowns are readily identified after cutting because blackened tissue can be seen in the cross section of the stem. After cutting, infected plants may regrow more slowly than healthy plants.
Comments on the Disease
Little information is available on disease development of this problem. It is likely that the pathogen is spread to other plants by cutting machines, as researchers have transmitted the pathogen with cutting tools. The digging and splitting of diseased crowns for propagation purposes results in infected new plantings. The bacterium probably survives on both plant tissue and on dead organic matter.
Do not use infected crowns for propagation. Annually grown artichokes planted from seed or transplants may not develop this disease.