Cylindrocladium clavatum in Florida. E. L. Barnard, Florida Department of Agriculture & Consumer Services, P.O. Box 1269, Gainesville 32602. N. E. El-Gholl, T. S. Schubert, R. M. Leahy, and C. L. Schoulties. Florida Department of Agriculture & Consumer Services, P.O. Box 1269, Gainesville 32602, and 212 Barre Hall, Clemson University, Clemson, SC 29631. Plant Dis. 73:273. Accepted for publication 25 January 1989. Copyright 1989 The American Phytopathological Society. DOI: 10.1094/PD-73-0273D.
Cylindrocladium clavatum Hodges & May from roots of Araucaria angustifolia (Bert.) Kuntze, Eucalyptus sa ligna Sm., and Pinus spp. was described as a potential threat to exotic pine culture in Brazil because of its apparent virulence and field association with root disease of Pinus spp. (1). Unverified reports of C. clavatum associated with root rots of Rhododendron spp. and Callistemon citrinus (Curtis) Stapf appeared in 1984 (S. A. Alfieri et al. Index of Plant Diseases in Florida). Between 1982 and 1988 we have isolated C. clavatum from leaves of Strelitzia reginae Ait. and Callistemon sp., stems and roots of A. heterophylla (Salisb.) Franco (ATCC 64720), and roots of P. clausa (Chapm.) Vasey var. immuginata Ward (A TCC 64679) in environs ranging from ornamental nurseries in south and central Florida to a pine plantation in west Florida infected with Phytophthora cinnamomi Rands. Our findings extend the known distribution of C. clavatum into Florida and the continental United States and expand its known host range. Limited inoculations of A. heterophylla and Pinus spp. with the type (A TCC 22833) and ATCC 64720 produced few infections, and evidence that C. elavatum is a threat to plant/tree culture in Florida is lacking.