Foliar Stage of Phytophthora Blight of Macadamia. M. Aragaki, Plant Pathologist, Department of Plant Pathology, University of Hawaii, Honolulu 96822. J. Y. Uchida, Research Associate, Department of Plant Pathology, University of Hawaii, Honolulu 96822. Plant Dis. 64:483-484. Copyright 1980 American Phytopathological Society. DOI: 10.1094/PD-64-483.

Blighting of shoot terminals and young, unexpanded apical leaves of Macadamia integrifolia were shown to be caused by Phytophthora capsici and P. palmivora. Under greenhouse conditions, P. capsici remained viable on blighted leaves for at least 6 mo. Isolates of P. capsici from pepper, papaya, anthurium, and macadamia raceme and isolates of P. palmivora from Vanda, English ivy, papaya, and macadamia raceme all induced foliar blights of macadamia. Application of the name P. capsici to isolates with deciduous, long-pedicellate sporangia is briefly discussed.