First Report of Verticillium Wilt (V. albo-atrum) of Vinca major in California. S. T. Koike, Santa Barbara County Department of Agriculture, Santa Barbara, CA 93110. . Plant Dis. 72:1077. Accepted for publication 12 September 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-1077E.
In 1987 and 1988, a disease of vinca (Vinca Major L.) was seen in ornamental plantings in Santa Barbara County, California. Symptoms consisted of wilted leaves, reddish discoloration of stem xylem tissue and wilting and shriveling of ascending stems that resulted in "flags." A nonmicrosclerotial Verticillium species consistently isolated from affected stems was identified as V. albo-atrum Reinke & Berth. (2). Pathogenicity was confirmed by inoculating well-rooted, vegetatively propagated vinca that had been grown in a greenhouse for 1 mo after rooting. The roots of these plants were dipped into a conidial suspension (1x107conidia/ml) of the fungus. Symptoms appeared in 4 wk and the fungus was reisolated from the diseased plants. This is the first report of V. albo-atrum sensu stricto on V. major and one of the few records of this pathogen in California. V. albo-atrum has been found on cucumber, Ceanothus, Pelargonium, and alfalfa in the state (1). The isolate from vinca was found in the same area of coastal Santa Barbara County as the Pelargonium isolate. Records of V. albo-atrum sensu stricto in California, including this new report,, have come primarily from regions near the relatively cooler Pacific Coast.