VIEW ARTICLE

Etiology

Relation of Kretzschmaria clavus to Hypoxyloid Stromata on Diseased Macadamia Tissues. W. H. Ko, Professor, Department of Plant Pathology, University of Hawaii, Beaumont Agricultural Research Center, Hilo 96720; W. C. Ho(2), and R. K. Kunimoto(3). (2)Postdoctoral research fellow, Department of Plant Pathology, University of Hawaii, Beaumont Agricultural Research Center, Hilo 96720, Present address: Taiwan Seed Service, Shinshieh, Taichung, Taiwan; (3)Research associate, Department of Plant Pathology, University of Hawaii, Beaumont Agricultural Research Center, Hilo 96720. Phytopathology 72:1357-1358. Accepted for publication 30 March 1982. Copyright 1982 The American Phytopathological Society. DOI: 10.1094/Phyto-72-1357.

Hypoxyloid stromata were observed frequently on macadamia tissues infected by Kretzschmaria clavus. Ascospores from hypoxyloid stromata were similar in shape and size to those from typical K. clavus stromata. Colonies from ascospores derived from hypoxyloid stromata were similar to colonies from ascospores derived from kretzschmarioid stromata. Isolates from typical kretzschmarioid stromata and isolates from hypoxyloid stromata produced conidia similar in shape and size on sterilized stem tissues. Anastomoses occurred between hyphae derived from propagules from these two types of stromata. Isolates from kretzschmarioid stromata or from hypoxyloid stromata produced both kretzschmarioid and hypoxyloid stromata on litchi stem tissues. Results strongly suggest that the hypoxyloid stromata on diseased macadamia tissues are morphological variants of the more familiar K. clavus stromata.