Consumer Services Division of Plant Industry S. A. Alfieri, Jr., and J. W. Miller Christmas cactus, Zygocactus truncatus Schum., is grown as a potted ornamental, primarily for its showy flowers which occur in a variety of colors. Stems of diseased plants appear lifeless, having a dull, grey-green color, and droop much more severely than the gracefully arched healthy stems.
Infected roots are brown, soft, water-soaked, and necrotic.
Effective control of this disease lies in the use of pasteurized soil, the prevention of soil infestation by the fungus. Bureau of Plant Pathology, P. O. Box 1269, Gainesville, FL 32602. Literature Cited 1. Alfieri, S. A., Jr., and J. W. Miller. Bougainvillea blight, a new disease caused by Phytophthora parasitica.