Identification of a Virus Causing a Mosaic on Coleus. G. E. Holcomb, Professor, Department of Plant Pathology and Crop Physiology, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge 70803. R. A. Valverde, Assistant Professor, Department of Plant Pathology and Crop Physiology, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge 70803. Plant Dis. 75:1183-1185. Accepted for publication 15 July 1991. Copyright 1991 The American Phytopathological Society. DOI: 10.1094/PD-75-1183.

Viruslike symptoms of mosaic, oak-leaf line patterns, ring spots, and color fading were observed on landscape plantings of coleus (Coleus scutellarioides ‘Alabama’) and two unidentified coleus cultivars. Stocks of Alabama with similar symptoms were found commonly in a survey of local garden centers and landscape plantings. The suspected virus was transmitted mechanically to cowpea and back to coleus, on which it produced symptoms similar to those originally observed. The virus was identified as a strain of cucumber mosaic virus based on gel electrophoresis of dsRNA, serology, particle morphology, and host reaction.