Pseudocercospora nigricans, a Pathogen of Sicklepod (Cassia obtusifolia) with Biocontrol Potential. F. M. Hofmeister, Biological Scientist, Department of Plant Pathology, University of Florida, Gainesville 32611. R. Charudattan, Professor, Department of Plant Pathology, University of Florida, Gainesville 32611. Plant Dis. 71:44-46. Accepted for publication 31 May 1986. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0044.

A fungus, Pseudocercospora nigricans, isolated from foliar lesions on diseased sicklepod (Cassia obtusifolia) was determined to be the causal agent of the observed disease. Symptoms consisted of chlorosis, necrotic mottling of leaves, and accelerated leaf drop, which contributed to overall reduction of plant size. In host range studies conducted in the greenhouse, the fungus was pathogenic only to sicklepod but not to 23 crop and weed species in 10 plant families. Results of both greenhouse host range studies and pathogenicity studies in the field indicated this fungus may be useful as a classical biological control agent.

Keyword(s): weed control.