Association of Corynebacterium fascians with Fasciation Disease of Impatiens and Hebe in California. D. A. Cooksey, Department of Plant Pathology, University of California, Riverside 92521. R. Keim, University of California South Coast Field Station, Santa Ana 92705. Plant Dis. 67:1389. Accepted for publication 20 September 1983. Copyright 1983 American Phytopathological Society, 1983. DOI: 10.1094/PD-67-1389.

Stem fasciations were observed on about 90% of 1-yr-old Impatiens wallerana ‘Miniature Pink’ plants and about 20% of 1-yr-old Hebe speciosa ‘Rubra’ and H. elliptica ‘Variegata’ plants at a southern California nursery. The stunted plants had a proliferation of short (1–5 cm) shoots at the crown. Yellow-orange, slow-growing gram-positive bacteria were consistently isolated from the fasciated stem tissues at the base of the plants on yeast-dextrose-calcium carbonate agar and on D2 medium, selective for Corynebacterium. The bacteria induced strong fasciation symptoms when inoculated to 2-day-old pea seedlings and were therefore identified as C. fascians, extending the range of fasciation diseases associated with this pathogen to the family Balsaminaceae and to the genus Hebe of the family Scrophulariaceae.