Rhizoctonia solani Anastomosis Groupings in Carnation Fields and Their Pathogenicity to Carnation. E. E. Trujillo, Professor, Department of Plant Pathology, University of Hawaii, 3190 Maile Way, Honolulu 96822. R. Shimabuku, C. A. Cavin, and M. Aragaki. Research Associates, and Professor, Department of Plant Pathology, University of Hawaii, 3190 Maile Way, Honolulu 96822. Plant Dis. 72:863-865. Accepted for publication 19 May 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-0863.

Isolations from carnation stem rot and from soil in carnation problem fields yielded high numbers of Rhizoctonia solani-like fungi. Approximately 70% of soil isolates were R. solani, the remainder were binucleated fungi. Approximately 70% of R. solani from soil were AG-4, 20% were AG-2-2, and 10% were AG-2-1, AG-2-2 was pathogenic to carnation, AG-4 was weakly pathogenic, and AG-2-1 was avirulent. Among carnation cultivars, Atlantis and Red Diamond were the most resistant of nine cultivars tested. R. solani AG-2-2 was recovered from soil of two farms out of 11 surveyed.

Keyword(s): multinucleate.