Entire plant may be rotted and covered with gray mold. A slimy rot may proceed upward into head. Plant in well-drained soil. Destroy infected plants. Remove infected refuse from area.
Leaves have green and yellow mottling.
Absence of heading. Destroy weed hosts, such as groundswell wild lettuce. Insecticide program to control aphids. Consult the Plant Disease Clinic for more information on serological testing for virus identification provided by Dr. Om Sehgal.